0001583648-22-000016 | 10-K | XBRL Viewer | Pieris Pharmaceuticals INC

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 117,764	$ 70,436
Accounts receivable	3,313	1,706
Prepaid expenses and other current assets	6,548	3,579
Total current assets	127,625	75,721
Property and equipment, net	19,122	22,046
Operating lease right-of-use assets	3,909	3,934
Other non-current assets	2,904	3,309
Total assets	153,560	105,010
Current liabilities:
Accounts payable	8,609	1,787
Accrued expenses and other current liabilities	16,836	7,731
Deferred revenues, current portion	25,116	12,627
Total current liabilities	50,561	22,145
Deferred revenue, net of current portion	38,403	35,900
Operating lease liabilities	13,841	15,932
Other long-term liabilities	0	6
Total liabilities	102,805	73,983
Stockholders’ equity:
Convertible preferred stock, $0.001 par value per share, 10,000,000 shares authorized and 15,617 and 14,429 shares issued and outstanding at December 31, 2021 and 2020, respectively	0	0
Common stock, $0.001 par value per share, 300,000,000 shares authorized and 72,222,661 and 56,002,815 shares issued and outstanding at December 31, 2021 and 2020, respectively	72	56
Additional paid-in capital	306,998	242,672
Accumulated other comprehensive income (loss)	829	(295)
Accumulated deficit	(257,144)	(211,406)
Total stockholders’ equity	50,755	31,027
Total liabilities and stockholders’ equity	$ 153,560	$ 105,010

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2021	Aug. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock, par value (USD per share)	$ 0.001		$ 0.001
Preferred stock, shares authorized (shares)	10,000,000		10,000,000
Preferred stock, shares issued (shares)	15,617		14,429
Preferred stock, shares outstanding (shares)	15,617		14,429
Par value of common stock (USD per share)	$ 0.001	$ 0.001	$ 0.001
Common stock, shares authorized (shares)	300,000,000		300,000,000
Common stock, shares issued (shares)	72,222,661		56,002,815
Common stock, shares outstanding (shares)	72,222,661		56,002,815

CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Revenues [Abstract]
Customer revenue	$ 27,940	$ 23,911
Collaboration revenue	3,478	5,412
Total revenue	31,418	29,323
Operating expenses
Research and development	66,656	46,531
General and administrative	16,593	16,713
Total operating expenses	83,249	63,244
Loss from operations	(51,831)	(33,921)
Other income (expense)
Interest income	4	511
Grant income	3,685	0
Other income (expense), net	2,404	(3,656)
Loss before income taxes	(45,738)	(37,066)
Income tax provision	0	164
Net loss	(45,738)	(37,230)
Foreign currency translation	1,124	1,630
Unrealized gain on available-for-sale securities	0	70
Comprehensive loss	$ (44,614)	$ (35,530)
Net loss per share:
Basic (in dollars per share)	$ (0.71)	$ (0.68)
Diluted (in dollars per share)	$ (0.71)	$ (0.68)
Weighted average number of common shares outstanding used in net loss per share attributable to common stockholders
Weighted average number of common shares outstanding, basic (in shares)	64,547	54,481
Weighted average number of common shares outstanding, diluted (in shares)	64,547	54,481

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	At the market offering	Private Placement	Convertible preferred shares	Convertible preferred shares At the market offering	Convertible preferred shares Private Placement	Common shares	Common shares At the market offering	Common shares Private Placement	Additional paid-in capital	Additional paid-in capital At the market offering	Additional paid-in capital Private Placement	Accumulated other comprehensive income (loss)	Accumulated deficit
Balance at beginning of period (shares) at Dec. 31, 2019				11,000			55,212,000
Balance at beginning of period at Dec. 31, 2019	$ 51,352			$ 0			$ 55			$ 227,468			$ (1,995)	$ (174,176)
Increase (Decrease) in Stockholders' Equity
Net loss	(37,230)													(37,230)
Foreign currency translation adjustment	1,630												1,630
Unrealized gain on investments	70												70
Stock based compensation expense	5,090									5,090
Issuance of common stock resulting from exercise of stock options (shares)							149,000
Issuance of common stock resulting from exercise of stock options	$ 291									291
Issuance of common stock resulting from purchase of employee stock purchase plan shares (shares)	69,544						70,000
Issuance of common stock resulting from purchase of employee stock purchase plan shares	$ 200									200
Issuance of common stock resulting from exercise of warrants (shares)							0
Issuance of common stock resulting from exercise of warrants	0									0
Preferred stock conversion (shares)				3,000			(3,000,000)
Preferred stock conversion	0						$ (3)			3
Issuance of common stock pursuant to offering (in shares)					0			3,571,000
Issuance of common stock pursuant to offering value		$ 9,624						$ 4			$ 9,620
Balance at end of period (shares) at Dec. 31, 2020				14,000			56,003,000
Balance at end of period at Dec. 31, 2020	31,027			$ 0			$ 56			242,672			(295)	(211,406)
Increase (Decrease) in Stockholders' Equity
Net loss	(45,738)													(45,738)
Foreign currency translation adjustment	1,124												1,124
Stock based compensation expense	5,215									5,215
Issuance of common stock resulting from exercise of stock options (shares)							482,000
Issuance of common stock resulting from exercise of stock options	$ 1,024									1,024
Issuance of common stock resulting from purchase of employee stock purchase plan shares (shares)	64,257						64,000
Issuance of common stock resulting from purchase of employee stock purchase plan shares	$ 165									165			0	0
Issuance of common stock resulting from exercise of warrants (shares)							1,391,000
Issuance of common stock resulting from exercise of warrants	837						$ 1			836
Issuance of common stock resulting from conversion of preferred stock (shares)				(4,000)			3,812,000
Issuance of common stock resulting from conversion of preferred stock	0			$ 0			$ 4			(4)
Preferred stock conversion (shares)				5,000			(5,000,000)
Preferred stock conversion	0			$ 0			$ (5)			5
Issuance of common stock pursuant to offering (in shares)					0	0		8,180,000	7,290,000
Issuance of common stock pursuant to offering value		$ 38,188	$ 18,913					$ 8	$ 8		$ 38,180	$ 18,905
Balance at end of period (shares) at Dec. 31, 2021				16,000			72,222,000
Balance at end of period at Dec. 31, 2021	$ 50,755			$ 0			$ 72			$ 306,998			$ 829	$ (257,144)

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
At the market offering
Payments for stock issuance costs	$ 1.5	$ 0.4
Private Placement
Payments for stock issuance costs	$ 0.1

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating activities:
Net loss	$ (45,738)	$ (37,230)
Adjustments to reconcile net loss to net cash (used in) operating activities:
Depreciation and amortization	2,459	2,311
Right-of-use asset amortization	(91)	(184)
Stock-based compensation	5,215	5,090
Other non-cash transactions	(30)	(133)
Realized investment gain/loss	0	471
Deferred tax expense	0	164
Foreign currency re-measurement loss	0	(8)
Changes in operating assets and liabilities:
Accounts receivable	(1,813)	5,343
Prepaid expenses and other assets	(3,154)	(500)
Deferred revenue	19,555	(14,496)
Accounts payable	7,049	(4,354)
Accrued expenses and other current liabilities	9,876	(1,655)
Lease liabilities	(988)	(715)
Net cash used in operating activities	(7,660)	(45,896)
Investing activities:
Purchase of property and equipment	(949)	(2,726)
Proceeds from maturities of investments	0	83,437
Purchase of investments	0	(41,499)
Net cash (used in) provided by investing activities	(949)	39,212
Financing activities:
Proceeds from exercise of options	1,024	291
Proceeds from employee stock purchase plan	165	200
Proceeds from exercise of warrants	837	0
Proceeds from issuance of common stock resulting from ATM sales, net of $1.5 million in transaction costs	38,188	9,624
Proceeds from issuance of common stock from private placement, net of $0.1 million in issuance costs	18,913	0
Net cash provided by financing activities	59,127	10,115
Effect of exchange rate change on cash and cash equivalents	(3,190)	4,745
Net increase in cash and cash equivalents	47,328	8,176
Cash and cash equivalents at beginning of year	70,436	62,260
Cash and cash equivalents at end of year	117,764	70,436
Supplemental cash flow disclosures:
Property and equipment included in accounts payable	$ 237	$ 131

CONSOLIDATED STATEMENTS OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
At the market offering
Payments for stock issuance costs	$ 1.5	$ 0.4
Private Placement
Payments for stock issuance costs	$ 0.1

Corporate Information	12 Months Ended
Corporate Information	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Corporate Information	Corporate Information Pieris Pharmaceuticals, Inc., was founded in May 2013, and acquired 100% interest in Pieris Pharmaceuticals GmbH (formerly Pieris AG, a German company which was founded in 2001) in December 2014. Pieris Pharmaceuticals, Inc. and its wholly-owned subsidiaries, hereinafter collectively Pieris, or the Company, is a clinical-stage biopharmaceutical company that discovers and develops Anticalin-based drugs to target validated disease pathways in unique and transformative ways. Pieris' corporate headquarters is located in Boston, Massachusetts and its research facility, as of December 31, 2021, was located in Hallbergmoos, Germany. Pieris’ clinical pipeline includes an inhaled IL-4Rα antagonist Anticalin protein to treat moderate-to-severe asthma and an immuno-oncology, or IO, bispecific targeting 4-1BB and HER2. The Company’s core Anticalin technology and platform was developed in Germany, and the Company has partnership arrangements with several major multi-national pharmaceutical companies. The Company is subject to risks common to companies in the biotechnology industry, including but not limited to, the need for additional capital, risks of failure of preclinical studies and clinical trials, the need to obtain marketing approval and reimbursement for any drug product candidate that it may identify and develop, the need to successfully commercialize and gain market acceptance of its product candidates, dependence on key personnel, protection of proprietary technology, compliance with government regulations, development of technological innovations by competitors, reliance on third party manufacturers and the ability to transition from pilot-scale production to large-scale manufacturing of products. As of December 31, 2021, cash and cash equivalents were $117.8 million. The Company’s net loss was $45.7 million and $37.2 million for the years ended December 31, 2021 and 2020, respectively. The Company has incurred net losses since inception and had an accumulated deficit of $257.1 million as of December 31, 2021. Net losses and negative cash flows have had, and will continue to have, an adverse effect on the Company’s stockholders’ equity and working capital. The Company expects to continue to incur operating losses for at least the next several years. The future success of the Company is dependent on its ability to identify and develop its product candidates, expand its corporate infrastructure and ultimately upon its ability to attain profitable operations. The Company has devoted substantially all of its financial resources and efforts to research and development and general and administrative expenses to support such research and development. The Company has several research and development programs underway in varying stages of development and it expects that these programs will continue to require increasing amounts of cash for development, conducting clinical trials, and testing and manufacturing of product material. Cash necessary to fund operations will increase significantly over the next several years as the Company continues to conduct these activities necessary to pursue governmental regulatory approval of clinical-stage programs and other product candidates. The Company plans to raise additional capital to fulfill its operating and capital requirements through public or private equity financings, utilization of its current ATM program, strategic collaborations, licensing arrangements, government grants and/or the achievement of milestones under its collaborative agreements. The funding requirements of the Company’s operating plans, however, are based on estimates that are subject to risks and uncertainties and may change as a result of many factors currently unknown. Although management continues to pursue these funding plans, there is no assurance that the Company will be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all. Until such time as the Company can generate substantial product revenues, if ever, the Company expects to finance its cash needs through a combination of equity offerings, debt financings, strategic partnerships, government grants and licensing arrangements. The terms of any future financing may adversely affect the holdings or the rights of the Company’s existing stockholders. The Company believes that its currently available funds will be sufficient to fund the Company’s operations through at least the next twelve months from the issuance of this Annual Report on Form 10-K. The Company's belief with respect to its ability to fund operations is based on estimates that are subject to risks and uncertainties. If actual results are different from management’s estimates, the Company may need to seek additional funding. If the Company is unable to obtain additional funding on acceptable terms when needed, it may be required to defer or limit some or all of its research, development, and/or clinical projects.

Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

Basis of Presentation and Use of Estimates

The accompanying consolidated financial statements of Pieris Pharmaceuticals, Inc. and its wholly-owned subsidiaries were prepared in accordance with U.S. GAAP. The consolidated financial statements include the accounts of all subsidiaries. All intercompany balances and transactions have been eliminated.

The preparation of the financial statements in accordance with U.S. GAAP requires management to make estimates, judgments, and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses and the related disclosures at the date of the financial statements and during the reporting period. Significant estimates are used for, but are not limited to, revenue recognition; deferred tax assets, deferred tax liabilities and valuation allowances; determination of the incremental borrowing rate to calculate right-of-use assets and lease liabilities; beneficial conversion features; fair value of stock options, preferred stock, and warrants; and prepaid and accrued clinical trial expenses. Management evaluates its estimates on an ongoing basis. Actual results and outcomes could differ materially from management’s estimates, judgments, and assumptions.

Foreign Currency Translation

The financial statements of the Company’s foreign subsidiaries are translated from local currency into reporting currency, which is U.S. dollars, using the current exchange rate at the balance sheet date for assets and liabilities, and the weighted average exchange rate prevailing during the period for revenues and expenses. The functional currency for Pieris’ foreign subsidiaries is considered to be the local currency for each entity and, accordingly, translation adjustments for these subsidiaries are included in accumulated other comprehensive loss within stockholders’ equity.

Realized and unrealized gains and losses resulting from foreign currency transactions denominated in currencies other than the functional currency are reflected as other (expense) income, net in the consolidated statements of operations. Foreign currency gains and losses on available-for-sale investment transactions are recorded to other comprehensive income (loss) on the Company's balance sheet per Financial Accounting Standards Board, or FASB, Accounting Standards Codification, or ASC, Topic 830, Foreign Currency Matters.

Cash, Cash Equivalents and Investments

The Company determines the appropriate classification of its investments at the time of purchase. All liquid investments with original maturities of 90 days or less from the purchase date and for which there is an active market are considered to be cash equivalents. The Company’s investments are comprised of money market, asset backed securities, government treasuries, and corporate bonds that are classified as available-for-sale in accordance with FASB ASC 320, Investments—Debt and Equity Securities. The Company classifies investments available to fund current operations as current assets on its balance sheets.

Available-for-sale investments are recorded at fair value, with unrealized gains or losses included in accumulated other comprehensive income (loss) on the Company’s balance sheets. Realized gains and losses are determined using the specific identification method and are included as a component of other income (expense).

The Company reviews investments for other-than-temporary impairment whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. To determine whether an impairment is other-than temporary, the Company considers its intent to sell, or whether it is more likely than not that the Company will be required to sell the investment before recovery of the investment’s amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, the severity and the duration of the impairment, and changes in value subsequent to period end.

Concentration of Credit Risk and Off-Balance Sheet Risk

The Company has no financial instruments with off‑balance sheet risk such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Financial instruments that subject Pieris to concentrations of credit risk include cash and cash equivalents, investments, and accounts receivable. The Company’s cash, cash equivalents, and investments are held in accounts with financial institutions that management believes are creditworthy. The Company’s investment policy includes guidelines on the quality of the institutions and financial instruments and defines allowable investments that the Company believes minimizes the exposure to concentration of credit risk. The Company has not experienced any credit losses in such accounts and does not believe it is exposed to any significant credit risk on these funds. Accounts receivable primarily consist of amounts due under strategic partnership and other license agreements with major multi-national pharmaceutical companies for which the Company does not obtain collateral.

Fair Value Measurement

The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. FASB ASC Topic 820, Fair Value Measurement and Disclosures, or ASC 820, established a hierarchy of inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the financial instrument based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the financial instrument and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported or disclosed fair value of the financial instruments and is not a measure of the investment credit quality. Fair value measurements are classified and disclosed in one of the following three categories:

•Level 1 inputs are quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date.

•Level 2 utilizes quoted market prices in markets that are not active, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency.

•Level 3 inputs are unobservable inputs for the asset or liability in which there is little, if any, market activity for the asset or liability at the measurement date.

To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement.

Financial instruments measured at fair value on a recurring basis include cash equivalents and investments, if any (Note 6).

An entity may elect to measure many financial instruments and certain other items at fair value at specified election dates. Subsequent unrealized gains and losses on items for which the fair value option has been elected will be reported in net loss. The Company did not elect to measure any additional financial instruments or other items at fair value.

Fair Values of Financial Instruments

The fair value of cash, accounts receivable, and accounts payable approximates the carrying value of these financial instruments because of the short-term nature of any maturities. The Company determines the estimated fair values of other financial instruments, using available market information and valuation methodologies, primarily input from independent third party pricing sources.

Accounts Receivable

Accounts receivable are recorded net of allowances for doubtful accounts and represent amounts due from strategic partners. The Company monitors and evaluates collectability of receivables on an ongoing basis and considers whether an allowance for doubtful accounts is necessary. The Company determined that no such reserve is needed as of December 31, 2021 and 2020. Historically, Pieris has not had collectability issues.

Property and Equipment

Property and equipment are recorded at acquisition cost, less accumulated depreciation and impairment. Depreciation on property and equipment is calculated using the straight-line method over the remaining estimated useful lives of the assets. Maintenance and repairs to these assets are charged to expenses as occurred. During the year ended December 31, 2020, the Company added material assets related to the February 2020 move to a new research and development facility in Hallbergmoos, Germany. Substantially all of the Company's fixed assets are located in Germany. The estimated useful life of the different groups of property and equipment is as follows:


Asset Classification						Estimated useful life (in years)
Leasehold improvements						shorter of useful life or remaining life of the lease
Laboratory furniture and equipment						8 - 14
Office furniture and equipment						5 - 13
Computer and equipment						3 - 7

Impairment of Long-lived Assets

The Company reviews its long-lived assets to be held and used for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. The Company evaluates the realizability of its long-lived assets based on profitability and cash flow expectations for the related asset. Any write-downs are treated as permanent reductions in the carrying amount of the assets. The Company believes that, as of each of the balance sheets presented, none of the Company’s long-lived assets were impaired.

Revenue Recognition

Pieris has entered into several licensing agreements with collaboration partners for the development of Anticalin therapeutics against a variety of targets. The terms of these agreements provide for the transfer of multiple goods or services which may include: (i) licenses, or options to obtain licenses, to Pieris’ Anticalin technology and/or specific programs and (ii) research and development activities to be performed on behalf of or with a collaborative partner. Payments to Pieris under these agreements may include upfront fees (which include license and option fees), payments for research and development activities, payments based upon the achievement of certain milestones, and royalties on product sales. There are no performance, cancellation, termination or refund provisions in any of the arrangements that could result in material financial consequences to Pieris. As the Company's intellectual property is located in Germany, the Company records all consolidated revenue in its Pieris Pharmaceuticals, GmbH subsidiary.

Collaborative Arrangements

The Company considers the nature and contractual terms of an arrangement and assess whether the arrangement involves a joint operating activity pursuant to which it is an active participant and exposed to significant risks and rewards with respect to the arrangement. If the Company is an active participant and exposed to the significant risks and rewards with respect to the arrangement, it accounts for these arrangements pursuant to ASC 808, Collaborative Arrangements, or ASC 808, and applies a systematic and rational approach to recognize revenue. The Company classifies payments received as revenue and payments made as a reduction of revenue in the period in which they are earned. Revenue recognized under a collaborative arrangement involving a participant that is not a customer is presented as Collaboration Revenue in the Statement of Operations.

In November 2018, the FASB issued ASU 2018-18, which makes targeted improvements to U.S. GAAP for collaborative arrangements, including: clarification that certain transactions between collaborative arrangement participants should be accounted for as revenue under ASC 606, Revenue from Contracts with Customers, or ASC 606, when the collaborative arrangement participant is a customer in the context of a unit of account; adding unit-of-account guidance in ASC 808 to align with the guidance in ASC 606; and a requirement that in a transaction with a collaborative arrangement participant that is not directly related to sales to third parties, presenting the transaction together with revenue recognized under ASC 606 is precluded if the collaborative arrangement participant is not a customer. The guidance per ASU 2018-18 was adopted retrospectively to the date of initial application of ASC 606. The Company adopted ASU 2018-18 in the first quarter of 2020. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements; however, revenue recognized under a collaborative arrangement involving a participant that is not a customer (Collaboration revenue) is now presented separately from Customer revenue. All amounts presented herein are in conformity with ASU 2018-18.

Revenue from Contracts with Customers

In accordance with ASC 606, revenue is recognized when a customer obtains control of promised goods or services. The amount of revenue recognized reflects the consideration to which the Company expects to be entitled in exchange for these goods and services. To achieve this core principle, the Company applies the following five steps: 1) identify the customer contract; 2) identify the contract’s performance obligations; 3) determine the transaction price; 4) allocate the transaction price to the performance obligations; and 5) recognize revenue when or as a performance obligation is satisfied.

The Company evaluates all promised goods and services within a customer contract and determines which of such goods and services are separate performance obligations. This evaluation includes an assessment of whether the good or service is capable

of being distinct and whether the good or service is separable from other promises in the contract. In assessing whether promised goods or services are distinct, the Company considers factors such as the stage of development of the underlying intellectual property and the capabilities of the customer to develop the intellectual property on their own or whether the required expertise is readily available.

Licensing arrangements are analyzed to determine whether the promised goods or services, which often include licenses, research and development services and governance committee services, are distinct or whether they must be accounted for as part of a combined performance obligation. If the license is considered not to be distinct, the license would then be combined with other promised goods or services as a combined performance obligation. If the Company is involved in a governance committee, it assesses whether its involvement constitutes a separate performance obligation. When governance committee services are determined to be separate performance obligations, the Company determines the fair value to be allocated to this promised service.

Certain contracts contain optional and additional items, which are considered marketing offers and are accounted for as separate contracts with the customer if such option is elected by the customer, unless the option provides a material right which would not be provided without entering into the contract. An option that is considered a material right is accounted for as a separate performance obligation.

The transaction price is determined based on the consideration to which the Company will be entitled in exchange for transferring goods and services to the customer. A contract may contain variable consideration, including potential payments for both milestone and research and development services. For certain potential milestone payments, the Company estimates the amount of variable consideration by using the most likely amount method. In making this assessment, the Company evaluates factors such as the clinical, regulatory, commercial and other risks that must be overcome to achieve the milestone. Each reporting period the Company re-evaluates the probability of achievement of such variable consideration and any related constraints. Pieris will include variable consideration, without constraint, in the transaction price to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. For potential research and development service payments, the Company estimates the amount of variable consideration by using the expected value method, including any approved budget updates arising from additional research or development services.

If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price among the performance obligations on a relative standalone selling price basis unless a portion of the transaction price is variable and meets the criteria to be allocated entirely to a performance obligation or to a distinct good or service that forms part of a single performance obligation.

The Company allocates the transaction price based on the estimated standalone selling price of the underlying performance obligations or in the case of certain variable consideration to one or more performance obligations. The Company must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. The Company utilizes key assumptions to determine the stand-alone selling price, which may include other comparable transactions, pricing considered in negotiating the transaction and the estimated costs to complete the respective performance obligation. Certain variable consideration is allocated specifically to one or more performance obligations in a contract when the terms of the variable consideration relate to the satisfaction of the performance obligation and the resulting amounts allocated to each performance obligation are consistent with the amount the Company would expect to receive for each performance obligation.

When a performance obligation is satisfied, revenue is recognized for the amount of the transaction price, excluding estimates of variable consideration that are constrained, that is allocated to that performance obligation on a relative standalone selling price basis. Significant management judgment is required in determining the level of effort required under an arrangement and the period over which the Company is expected to complete its performance obligations under an arrangement.

For performance obligations consisting of licenses and other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non- refundable, up-front fees. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company will recognize revenue from non-refundable, up-front fees allocated to the license when the license is transferred to the customer and the customer is able to use and benefit from the license.

Revenue recognized under an arrangement involving a participant that is a customer is presented as Customer Revenue.

Milestones and Royalties

The Company aggregates milestones into four categories (i) research milestones, (ii) development milestones, (iii) commercial milestones and (iv) sales milestones. Research milestones are typically achieved upon reaching certain success criteria as defined in each agreement related to developing an Anticalin protein against the specified target. Development milestones are typically reached when a compound reaches a defined phase of clinical research or passes such phase, or upon gaining regulatory approvals. Commercial milestones are typically achieved when an approved pharmaceutical product reaches the status for commercial sale, including regulatory approval. Sales milestones are certain defined levels of net sales by the licensee, such as when a product first achieves global sales or annual sales of a specified amount.

There is uncertainty that the events to obtain the research and development milestones will be achieved given the nature of clinical development and the stage of the Company’s technology. The Company has thus determined that all research and development milestones will be constrained until it is deemed probable that a significant revenue reversal will not occur. For revenues from research and development milestones, payments will be recognized consistent with the recognition pattern of the performance obligation to which they relate.

For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and for which the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). Commercial milestones and sales royalties are determined by sales or usage-based thresholds and will be accounted for under the royalty recognition constraint as constrained variable consideration.

The Company calculates the maximum amount of potential milestones achievable under each collaboration agreement and discloses such potential future milestones for all current collaborations using such a maximum calculation.

Contract Balances

The Company recognizes a contract asset when the Company transfers goods or services to a customer before the customer pays consideration or before payment is due, excluding any amounts presented as a receivable (i.e., accounts receivable). A contract asset is an entity’s right to consideration in exchange for goods or services that the entity has transferred to a customer. The contract liabilities (i.e., deferred revenue) primarily relate to contracts where the Company has received payment but has not yet satisfied the related performance obligations.

In the event of an early termination of a collaboration agreement, any contract liabilities would be recognized in the period in which all Company obligations under the agreement have been fulfilled.

Costs to Obtain and Fulfill a Contract with a Customer

Certain costs to obtain customer contracts, including success-based fees paid to third-party service providers, and costs to fulfill customer contracts are capitalized in accordance with FASB ASC 340, Other Assets and Deferred Costs, or ASC 340. These costs are amortized to expense on a systemic basis that is consistent with the transfer to the customer of the goods or services to which the asset relates. The Company will expense the amortization of costs to obtain customer contracts to general and administrative expense and costs to fulfill customer contracts to research and development expense.

Research and Development

Research and development expenses are charged to the statement of operations as incurred. Research and development expenses are comprised of costs incurred in performing research and development activities, including salaries and benefits, facilities costs, pre-clinical and clinical costs, contract services, consulting, depreciation and amortization expense, and other related costs. Costs associated with acquired technology, in the form of upfront fees or milestone payments, are charged to research and development expense as incurred.

Income Taxes

The Company applies ASC Topic 740 Income Taxes, which established financial accounting and reporting requirements for the effects of income taxes that result from the Company’s activities during the current and preceding years. Deferred tax assets and

liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, and operating losses and tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted statutory tax rates expected to apply to taxable income in the jurisdictions and years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Where the Company determines that it is more likely than not that some portion or all of the deferred tax assets will not be realized in the future, the deferred tax assets are reduced by a valuation allowance. The Company records interest and penalties related to uncertain tax positions as part of income tax expense.

The Tax Cuts and Jobs Act (TCJA) subjects a U.S. shareholder to tax on global-intangible low tax income (GILTI) earned by certain foreign subsidiaries. The Company has made an accounting policy election to provide for the tax expense related to GILTI in the year the tax is incurred as a period expense only.

Stock-based Compensation

The Company measures share-based payments in accordance with ASC Topic 718, Stock Compensation. Pieris records its stock-based compensation expense over the requisite service period and records forfeitures as they occur. Determining the appropriate fair value model and related assumptions requires judgment, including estimating share price volatility and expected terms of the awards. For employee options, the fair value measurement date is generally on the date of grant and the related compensation expense is recognized on a straight-line basis over the requisite service period of the awards, less expense for actual forfeitures.

The Company uses the Black-Scholes option pricing model to determine the estimated fair value for stock-based awards. Option-pricing models require the input of various subjective assumptions, including the option’s expected life, expected dividend yield, price volatility, risk free interest rate and forfeitures of the underlying stock. Due to the limited operating history of the Company as a public entity and a lack of company specific historical and implied volatility data, the Company has based its estimate of expected volatility on the historical volatility of a group of similar companies that are publicly traded. When selecting these public companies on which it has based its expected stock price volatility, the Company selected companies with comparable characteristics to it, including enterprise value, risk profiles, position within the industry, and with historical

share price information sufficient to meet the expected term of the stock-based awards. The Company computes historical volatility data using the daily closing prices for the selected companies’ shares during the equivalent period of the calculated expected term of the stock-based awards. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available.

Due to the lack of Company specific historical option activity, the Company has estimated the expected term of its employee stock options using the “simplified” method, whereby, the expected term equals the arithmetic average of the vesting term and the original contractual term of the option. The expected term for non-employee awards is the remaining contractual term of the option. The risk-free interest rates are based on the U.S. Treasury securities with a maturity date commensurate with the expected term of the associated award. The Company has never paid, and does not expect to pay dividends in the foreseeable future.

All excess tax benefits and tax deficiencies are recorded as income tax expense or benefit in the Company's statement of operations and comprehensive loss. For the years ended December 31, 2021 and 2020, the Company did not record an income statement benefit for excess tax benefits as a valuation allowance is also required on these amounts.

Government Grants

The Company recognizes grants from governmental agencies when there is reasonable assurance that the Company will comply with the conditions attached to the grant arrangement and the grant will be received. The Company evaluates the conditions of each grant as of each reporting period to evaluate whether the Company has reached reasonable assurance of meeting the conditions of each grant arrangement and that it is expected that the grant will be received as a result of meeting the necessary conditions. Grants are recognized in the consolidated statements of operations on a systematic basis over the periods in which the Company recognizes the related costs for which the government grant is intended to compensate. Specifically, grant income related to research and development costs is recognized as such expenses are incurred. Grant income is included as a separate caption within Other income (expense), net in the consolidated statements of operations.

Leases

The Company accounts for leases pursuant to ASC 842 Leases (Topic 842), or ASC 842. As a lessee, the Company is required to recognize (i) a lease liability, which is a lessees obligation to make lease payments arising from a lease, measured on a discounted basis; and (ii) a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term for all leases (with the exception of short-term leases) at the commencement date. Any variable components of lease costs are excluded from lease payments and are recognized in the period incurred.

The Company determines if an arrangement is a lease at inception. The Company’s contracts are determined to contain a lease within the scope of ASC 842 when all of the following criteria based on the specific circumstances of the arrangement are met: (1) there is an identified asset for which there are no substantive substitution rights; (2) the Company has the right to obtain substantially all of the economic benefits from the identified asset; and (3) the Company has the right to direct the use of the identified asset. In addition, the Company does not apply the recognition requirements in the lease standard to short-term leases (a lease that at commencement date has a lease term of 12 months or less and does not contain a purchase option that it is reasonably certain to exercise) and does not separate lease and non-lease components for all asset classes. Any variable components of lease costs are excluded from lease payments and are recognized in the period incurred.

At the commencement date, operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of future lease payments over the expected lease term. The Company’s lease agreements do not provide an implicit rate. As a result, the Company utilizes an estimated incremental borrowing rate to discount lease payments, which is based on the rate of interest the Company would have to pay to borrow a similar amount on a collateralized basis over a similar term and based on observable market data points. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or lease incentives received. Operating lease cost is recognized over the expected term on a straight-line basis.

The Company typically only includes an initial lease term in its assessment of a lease agreement. Options to renew a lease are not included in the Company’s assessment unless there is reasonable certainty that the Company will renew. The expected lease term includes noncancelable lease periods and, when applicable, periods covered by an option to extend the lease if the Company is reasonably certain to exercise that option, as well as periods covered by an option to terminate the lease if the Company is reasonably certain not to exercise that option.

Assumptions made by the Company at the commencement date are re-evaluated upon occurrence of certain events, including a lease modification. A lease modification results in a separate contract when the modification grants the lessee an additional right of use not included in the original lease and when lease payments increase commensurate with the standalone price for the additional right of use. When a lease modification results in a separate contract, it is accounted for in the same manner as a new lease.

Contingencies

Accruals are recorded for loss contingencies when it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. The Company evaluates, on a quarterly basis, developments in legal proceedings and other matters that could cause an increase or decrease in the amount of the liability that has been accrued previously. Considering facts known at the time of the assessment, the Company determines whether potential losses are considered reasonably possible or probable and whether they are estimable. Based upon this assessment, the Company carries out an evaluation of disclosure requirements and considers possible accruals in the financial statements.

Segment Reporting

Operating segments are identified as components of an enterprise where separate discrete financial information is evaluated by the chief operating decision maker in making decisions on how to allocate resources and assess performance. The Company operates as a single segment dedicated to the discovery and development of biotechnological applications and the Company’s chief operating decision maker, or CODM, makes decisions based on the Company as a whole. The Company has determined that its CODM is its Chief Executive Officer.

Earnings per Share

Basic earnings per share attributable to common stockholders is calculated by dividing net loss attributable to common stockholders by the weighted average shares outstanding during the period, without consideration for common stock equivalents.

Diluted earnings per share attributable to common stockholders is calculated by adjusting weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock and if-converted methods. For purposes of the diluted net loss per share attributable to common stockholders' calculation, preferred stock, stock options, unvested restricted stock, and warrants are considered to be common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders, as their effect would be anti-dilutive for all periods presented. Therefore, basic and diluted net loss per share were the same for all periods presented.

Recent Accounting Pronouncement Adopted

In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes which amends and aims to simplify accounting disclosure requirements regarding a number of topics including intraperiod tax allocation, accounting for deferred taxes when there are changes in consolidation of certain investments, tax basis step up in an acquisition and the application of effective rate changes during interim periods, among other improvements. This standard is effective for fiscal years beginning after December 15, 2020 and was adopted by the Company on January 1, 2021. Adoption of this new standard did not have a material impact on the Company.

In November 2021, the FASB issued ASU No. 2021-10, Government Assistance (Topic 832), or ASU 2021-10. ASU 2021-10 provides clarity on increasing transparency over the disclosure of certain government assistance including the disclosure of (1) the types of assistance, (2) an entity’s accounting for the assistance, and (3) the effect of the assistance on an entity’s financial statements. Diversity currently exists in the recognition, measurement, presentation, and disclosure of government assistance received by business entities because of the lack of specific authoritative guidance in generally accepted accounting principles. The guidance in ASU 2021-10 is effective for the Company for financial statements issued for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company adopted this standard for the period ended December 31, 2021 on a prospective basis and concluded that we have made the required disclosure in Footnote 5 below.

Recent Accounting Pronouncements Not Yet Adopted

In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Statements, or ASU 2016-13. ASU 2016-13 significantly changes the impairment model for most financial assets and certain other instruments. The new standard requires that expected credit losses relating to financial assets measured on an amortized cost basis and available-for-sale debt securities be recorded through an allowance for credit losses. It also limits the amount of credit losses to be recognized for available-for-sale debt securities to the amount by which carrying value exceeds fair value, and requires the reversal of previously recognized credit losses if fair value increases. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the financial asset(s) to present the net carrying value at the amount expected to be collected on the financial asset.

Subsequently, in November 2018, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, which clarifies codification and corrects unintended application of the guidance. In November 2019, the FASB issued ASU No. 2019-11, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, which clarifies or addresses specific issues about certain aspects of ASU 2016-13. In November 2019 the FASB also issued ASU No. 2019-10, Financial Instruments-Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842): Effective Dates, which delays the effective date of ASU 2016-13 by three years for certain smaller reporting companies such as the Company. The guidance in ASU 2016-13 is effective for the Company for financial statements issued for fiscal years beginning after December 15, 2022 and interim periods within those fiscal years, with early adoption permitted. The Company is still evaluating the impact of the adoption of this standard.

The Company has considered other recent accounting pronouncements and concluded that they are either not applicable to the business, or that the effect is not expected to be material to the unaudited consolidated financial statements as a result of future adoption.

Revenue

12 Months Ended

Dec. 31, 2021

Revenue from Contract with Customer [Abstract]

Revenue

General

The Company has not generated revenue from product sales. The Company has generated revenue from contracts with customers (option, license and collaboration agreements), which include upfront payments for licenses or options to obtain licenses, payments for research and development services and milestone payments.

During the years ended December 31, 2021 and 2020, respectively, the Company recognized revenue from the following strategic partnerships and other license agreements (in thousands):


	Years Ended December 31,
	2021		2020
AstraZeneca	$	18,919	$	8,308
Seagen	768		9,702
Servier	4,070		11,313
Boston Pharmaceuticals	5,711		—
Genentech	1,950		—
Total Revenue	$	31,418	$	29,323

Under the Company´s existing strategic partnerships and other license agreements, the Company could receive the following potential milestone payments (in millions) as of December 31, 2021:


	Research, Development, Regulatory & Commercial Milestones		Sales Milestones
AstraZeneca	$	1,096	$	4,275
Servier	136		102
Seagen	754		450
Boston Pharmaceuticals	88		265
Genentech	844		600
Total potential milestone payments	$	2,918	$	5,692

Strategic Partnerships

Genentech

On May 19, 2021, the Company and Genentech, Inc., or Genentech, entered into a Research Collaboration and License Agreement, or the Genentech Agreement, to discover, develop and commercialize locally delivered respiratory and ophthalmology therapies that leverage the Company’s proprietary Anticalin technology. Upon signing the Genentech Agreement, Genentech paid the Company a $20 million upfront fee. In addition, the Company may be eligible to receive additional milestone payments across multiple programs, as well as tiered royalty payments on net sales at percentages ranging from the mid-single to low double-digits, subject to certain standard reductions and offsets.

Under the terms of the Genentech Agreement, the Company will be responsible for discovery and preclinical development of two initial programs. The Company will be responsible for research activities following target nomination through the late-stage research go decision. The parties will then collaborate on drug candidate characterization until the development go decision. After the development go decision, Genentech will be responsible for pursuing the preclinical and clinical development of each program, and thereafter, the commercialization efforts. Each party will be responsible for the costs incurred to perform their respective responsibilities. Genentech has an option to expand the collaboration to encompass two additional programs with the payment of a $10 million fee per additional program. If Genentech exercises its option to start additional programs, payment to the Company of additional fees, milestone payments and royalties would result.

Unless earlier terminated, the term of the Genentech Agreement continues until no royalty or other payment obligations are or will become due under the Genentech Agreement. The Genentech Agreement may be terminated (i) by either party based on insolvency or breach by the other party and such insolvency proceeding is not dismissed or such breach is not cured within 90 days; or (ii) after 9 months from the effective date of the Genentech Agreement, by Genentech as a whole or on a product-by-product and/or country-by-country basis upon 90 days prior written notice before the first commercial sale of a product or upon 180 days prior written notice after the first commercial sale of a product.

While the Genentech Agreement allows for up to four research programs, only two research programs are initially identified and committed in the Genentech Agreement. To reach a total of up to four research programs, the Company has granted Genentech options to nominate an additional two collaboration targets of their choosing, subject to the legal availability of the target to be researched. Genentech will have three years after the effective date to nominate the subsequent targets. The Company has also granted Genentech options to replace any of the collaboration targets identified with another target.

However, at no point will there be more than four identified collaboration targets for which there are ongoing research programs.

The arrangement with Genentech provides for the transfer of the following goods or services: (i) exclusive research and commercial license for the collaboration programs, (ii) a non-exclusive platform improvement license, (iii) research and development services, (iv) participation in a governance committee, and (v) replacement target options on the first two programs upon a screening failure which were assessed as material rights.

Management evaluated all of the promised goods or services within the contract and determined which such goods and services were separate performance obligations. The Company determined that the licenses granted, at arrangement inception, should be combined with the research and development services to be provided for the related target programs as they are not capable of being distinct. A third party would not be able to provide the research and development services due to the specific nature of the intellectual property and knowledge required to perform the services, and Genentech could not benefit from the licenses without the corresponding services. The Company determined that the participation in the governance committees was distinct as the services could be performed by an outside party.

As a result, management concluded there were five separate performance obligations at the inception of the Genentech Agreement: (i) two combined performance obligations, each comprised of an exclusive research and commercial license, a non-exclusive platform improvement license, and research and development services for the first two Genentech programs, (ii) two performance obligations each comprised of a material right for a target swap option for the first two Genentech programs, and (iii) one performance obligation comprised of the participation on the governance committee.

The Company allocated consideration to the performance obligations based on the relative proportion of their standalone selling prices. The Company developed standalone selling prices for licenses by applying a risk adjusted, net present value, estimate of future potential cash flows approach, which included the cost of obtaining research and development services at arm’s length from a third-party provider, as well as internal full-time equivalent costs to support these services. The Company developed the standalone selling price for committee participation by using management’s estimate of the anticipated participation hours multiplied by a market rate for comparable participants.

The transaction price at inception is comprised of fixed consideration of $20.0 million in upfront fees and was allocated to each of the performance obligations based on the relative proportion of their standalone selling prices. The amounts allocated to the performance obligations for the two research programs will be recognized on a proportional performance basis through the completion of each respective estimated research term of the individual research programs. The amounts allocated to the material right for the target options will be recognized either at the time the material right expires or, if exercised, on a proportional performance basis over the estimated research term for that program along with any remaining deferred revenue associated with the replacement target. The amounts allocated to the participation on the committee will be recognized on a straight-line basis over the anticipated research term for all research programs. As of December 31, 2021, there was $16.6 million of aggregate transaction price allocated to remaining performance obligations.

Under the Genentech Agreement, the Company is eligible to receive various research, development, commercial and sales milestones. There is uncertainty that the events to obtain the research and development milestones will be achieved given the nature of clinical development and the stage of the Company’s technology. The Company has determined that all other research and development milestones will be constrained until it is deemed probable that a significant revenue reversal will not occur.

As of December 31, 2021, there were $8.1 million and $8.5 million of current and non-current deferred revenue, respectively, related to the Genentech Agreement.

Boston Pharmaceuticals

On April 24, 2021, the Company and BP Asset XII, Inc., or Boston Pharmaceuticals, a subsidiary of Boston Pharma Holdings, LLC, entered into an Exclusive Product License Agreement, or the BP Agreement, to develop PRS-342, a 4-1BB/GPC3 preclinical immuno-oncology Anticalin-antibody bispecific fusion protein.

Under the terms of the BP Agreement, Boston Pharmaceuticals exclusively licensed worldwide rights to PRS-342. The Company received an upfront payment of $10.0 million and is further entitled to receive development, regulatory and sales-based milestone payments, tiered royalties up to low double-digits on sales of PRS-342 and a percentage of consideration received by Boston Pharmaceuticals in the event of a sublicense of a program licensed under the BP Agreement or a change of control of Boston Pharmaceuticals. The Company will also contribute up to $4.0 million toward manufacturing activities.

The term of the BP Agreement ends upon the expiration of all of Boston Pharmaceuticals’ payment obligations thereunder. The BP Agreement may be terminated by Boston Pharmaceuticals in its entirety for convenience beginning nine months after its effective date upon 60 days’ notice or, for any program under the BP Agreement which has received marketing approval, upon 120 days’ notice. If any program is terminated by Boston Pharmaceuticals, the Company will have full rights to continue such program. The BP Agreement may also be terminated by Boston Pharmaceuticals or the Company for an uncured material breach by the other party upon 180 days’ notice (60 days in the case of non-payment of undisputed amounts due and payable), subject to extension for an additional 180 days in certain cases and subject, in all cases, to dispute resolution procedures. The Agreement may also be terminated due to the other party’s insolvency. The Company may also terminate the BP Agreement if Boston Pharmaceuticals challenges the validity of any patents licensed under the BP Agreement, subject to certain exceptions.

The Company does not have any obligations to assist in the research and development efforts of Boston Pharmaceuticals under the BP Agreement. However, the Company has an obligation to fund up to $4.0 million in costs, including out-of-pocket costs incurred by Boston Pharmaceuticals, in connection with the manufacture of products under the BP Agreement.

The arrangement with Boston Pharmaceuticals provides for the transfer of the following: (i) exclusive license of PRS-342, (ii) non-exclusive Pieris platform license, (iii) initial know-how, (iv) product cell line license, and (v) materials (as each such term is defined under the BP Agreement).

Management evaluated all of the promised goods or services within the BP Agreement and determined which such goods and services were separate performance obligations. The Company determined that the licenses granted, at arrangement inception, should be combined with the transfer of know-how, materials and the product cell line license. Boston Pharmaceuticals could not benefit from the exclusive and non-exclusive licenses without the corresponding transfer of know-how and materials.

As a result, management concluded there was only one combined performance obligation. The transaction price at inception is comprised of fixed consideration of $10.0 million in upfront fees, offset by $4.0 million in consideration payable to Boston Pharmaceuticals to reimburse them for expected out-of-pocket manufacturing costs, for a total transaction price of $6.0 million. Management has assessed the forms of variable consideration within the BP Agreement and concluded that the payments are either constrained by the royalty recognition constraint or because management has assessed the most likely amount associated with the payments as zero.

The amounts allocated to the performance obligations did not meet the criteria to be recognized over time on a proportional performance basis and thus will be recognized at a point in time. The Company determined that the performance obligation will be fully satisfied when all of the deliverables in the combined performance obligation are transferred to Boston Pharmaceuticals as that is the point at which Boston Pharmaceuticals can fully use and benefit from the license to PRS-342. The Company transferred all such deliverables to Boston Pharmaceuticals in the fourth quarter of 2021. As of December 31, 2021, the Company has recognized the full transaction price, or $5.7 million, as revenue and there is no remaining deferred revenue.

Seagen

On February 8, 2018, the Company entered into a license and collaboration agreement, or the Seagen Collaboration Agreement, and a non-exclusive Anticalin platform technology license agreement, or the Seagen Platform License, and together with the Seagen Collaboration Agreement, the Seagen Agreements, with Seagen, Inc., or Seagen, pursuant to which the parties will develop multiple targeted bispecific IO treatments for solid tumors and blood cancers.

Under the terms of the Seagen Agreements, the companies will pursue multiple Anticalin-antibody fusion proteins during the research phase. The Seagen Agreements provide Seagen a base option to select up to three programs for further development. Prior to the initiation of a pivotal trial, the Company may opt into global co-development and U.S. commercialization of the second program and share in global costs and profits on an equal basis. Seagen will solely develop, fund and commercialize the other two programs. Seagen may also decide to select additional candidates from the initial research phase for further development in return for the payment to us of additional fees, milestone payments, and royalties

The Seagen Platform License grants Seagen a non-exclusive license to certain intellectual property related to the Anticalin platform technology.

Upon signing the Seagen Agreements, Seagen paid the Company a $30.0 million upfront fee and an additional $4.9 million was estimated to be paid for research and development services as reimbursement to the Company through the end of the research term. In addition, the Company may receive tiered royalties on net sales up to the low double-digits and success-based research, development, commercial, and sales milestones payments across the product candidates, depending on the successful development and commercialization of those candidates. If Seagen exercises its option to select additional candidates from the initial research phase for further development, payment to Pieris of additional fees, milestone payments, and royalties would result.

The term of each of the Seagen Agreements ends upon the expiration of all of Seagen's payment obligations under each agreement. The Seagen Collaboration Agreement may be terminated by Seagen on a product-by-product basis for convenience beginning 12 months after its effective date upon 90 days' notice or, for any program where a pivotal study has been initiated, upon 180 days' notice. Any program may be terminated at Seagen's option. If any program is terminated by Seagen after a pre-defined pre-clinical stage, the Company will have full rights to continue such program. If any program is terminated by Seagen prior to such pre-defined pre-clinical stage, the Company will have the right to continue to develop such program, but will be obligated to offer a co-development option to Seagen for such program. The Seagen Collaboration Agreement may also be terminated by Seagen or the Company for an uncured material breach by the other party upon 90 days' notice, subject to extension for an additional 90 days if the material breach relates to diligence obligations and subject, in all cases, to dispute resolution procedures. The Seagen Collaboration Agreement may also be terminated due to the other party’s insolvency and may in certain instances, including for reasons of safety, be terminated on a product-by-product basis. Each party may also terminate the Seagen Agreements if the other party challenges the validity of any patents licensed under the Seagen Agreements, subject to certain exceptions. The Seagen Platform License will terminate upon termination of the Seagen Collaboration Agreement, whether in its entirety or on a product-by-product basis.

The Company determined that the Seagen Agreements should be combined and evaluated as a single arrangement under ASC 606 as they were executed on the same date. The arrangement with Seagen provides for the transfer of the following goods or services: (i) three candidate research licenses that each consist of a non-exclusive platform technology license, a co-exclusive candidate research license, and research and development services, (ii) research, development and manufacturing services associated with each candidate research license, (iii) participation on various governance committees, and (iv) two antibody target swap options which were assessed as material rights.

Management evaluated all of the promised goods or services within the contract and determined which such goods and services were separate performance obligations. The Company determined that the licenses granted, at arrangement inception, should be combined with the research and development services to be provided for the related antibody target programs as they are not capable of being distinct. A third party would not be able to provide the research and development services due to the specific nature of the intellectual property and knowledge required to perform the services, and Seagen could not benefit from the licenses without the corresponding services. The Company determined that the participation on the various governance committees was distinct as the services could be performed by an outside party.

As a result, management concluded there are six separate performance obligations at the inception of the Seagen Agreements: (i) three combined performance obligations, each comprised of a non-exclusive platform technology license, a co-exclusive candidate research license, and research and development services for the first three approved Seagen antibody target programs, (ii) two performance obligations each comprised of a material right for an antibody target swap option for the first and the second approved Seagen antibody target for no additional consideration, and (iii) one performance obligation comprised of the participation on the various governance committees.

The transaction price at inception is comprised of fixed consideration of $30.0 million in upfront fees and variable consideration of $4.9 million of estimated research and development services to be reimbursed as research and development occurs through the research term. The $30.0 million upfront fee, which represents the fixed consideration in the transaction price, was allocated to each of the performance obligations based on the relative proportion of their standalone selling prices. The $4.9 million in variable consideration related to the research and development services is allocated specifically to the three target program performance obligations based upon the budgeted services for each program

The amounts allocated to the performance obligations for the three research programs will be recognized on a proportional performance basis through the completion of each respective estimated research term of the individual research programs. The amounts allocated to the material right for the antibody target swap option will be recognized either at the time the material right expires, or if exercised, on a proportional performance basis over the estimated research term for that program. The amounts allocated to the participation on each of the committees will be recognized straight-line over the anticipated research term for all research programs. As of December 31, 2021, there was $21.5 million of aggregate transaction price allocated to remaining performance obligations.

In June 2020, Seagen and the Company entered into amendments to the Seagen Agreements, or together, the First Seagen Amendment. The Seagen Amendment extended the deadline for Seagen to nominate a second and third antibody target. As a result of the Seagen Amendment, which completed the remaining performance obligations under the research term for the first antibody target, the Company recorded $4.2 million of previously deferred revenue for the year ended December 31, 2020. The Company also recorded $5.0 million of milestone revenue in June 2020.

On March 24, 2021, the Company announced that Seagen made a strategic equity investment in Pieris, and that the companies had entered into a combination study agreement, or the Combination Study Agreement, to evaluate the safety and efficacy of combining Pieris’ cinrebafusp alfa with Seagen’s tucatinib, a small-molecule tyrosine kinase HER2 inhibitor, for the treatment of gastric cancer patients expressing lower HER2 levels (IHC2+/ISH- & IHC1+) as part of the upcoming phase 2 study to be conducted by Pieris. The companies have also entered into an Amended and Restated License and Collaboration Agreement, or the Second Seagen Amendment, in which their existing immuno-oncology collaboration agreement has been amended relating to joint development and commercial rights for the second program in the alliance.

Specifically, under the Second Seagen Amendment, Pieris’ option to co-develop and co-commercialize the second of three programs in the collaboration has been converted to a co-promotion option in the United States, with Seagen solely responsible for the development and overall commercialization of that program. Pieris will also be entitled to increased royalties from that program in the event that it chooses to exercise the co-promotion option. In connection with the agreements described above, the Company and Seagen entered into a subscription agreement, or the Seagen Subscription Agreement, pursuant to which the Company agreed to issue to Seagen, and Seagen agreed to acquire from the Company, 3,706,174 shares of the Company’s common stock for a total purchase price of $13.0 million, or $3.51 per share, in a private placement transaction pursuant to Section 4(a)(2) of the Securities Act of 1933, as amended. The Seagen Subscription Agreement includes a provision to the effect that Seagen may ask the Company to file a registration statement to register the resale of the shares issued to Seagen, at any time beginning on the date that is 60 calendar days from the date of issuance of the shares. The Company assessed the ASC 606 implications of the Seagen Subscription Agreement and concluded that the fair value of the shares on a per share basis was $2.61 per share as of the transaction date. This resulted in a premium paid for the shares of $3.3 million, all of which was recorded in deferred revenue upon contract execution and allocated to the remaining performance obligations.

The Company has concluded that the Combination Study Agreement is within the scope of ASC 808, which defines collaborative arrangements and addresses the presentation of the transactions between the two parties in the income statement and related disclosures. However, ASC 808 does not provide guidance on the recognition of consideration exchanged or accounting for the obligations that may arise between the parties. The Company has concluded that ASC 730, Research and Development, should be applied by analogy. There is no financial statement impact for the Combination Study Agreement as the value of the drug supply received from Seagen is offset against the drug supply cost.

Under the Seagen Agreements, the Company is eligible to receive various research, development, commercial and sales milestones. There is uncertainty that the events to obtain the research and development milestones will be achieved given the nature of clinical development and the stage of the Company’s technology. The Company has thus determined that all research and development milestones will be constrained until it is deemed probable that a significant revenue reversal will not occur.

As of December 31, 2021, there is $10.3 million and $8.2 million of current and non-current deferred revenue, respectively, related to the Seagen Agreements.

AstraZeneca

On May 2, 2017, the Company entered into a license and collaboration agreement, or the AstraZeneca Collaboration Agreement, and a non-exclusive Anticalin platform technology license agreement, or AstraZeneca Platform License, and together with the AstraZeneca Collaboration Agreement, the AstraZeneca Agreements with AstraZeneca AB, or AstraZeneca, which became effective on June 10, 2017, following expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976. Under the AstraZeneca Agreements the parties will advance several novel inhaled Anticalin proteins.

In addition to the Company’s lead inhaled drug candidate, PRS-060/AZD1402, or the AstraZeneca Lead Product, the Company and AstraZeneca, under the original terms of the the AstraZeneca Collaboration Agreement, would also collaborate to progress four additional novel Anticalin proteins against undisclosed targets for respiratory diseases, or the AstraZeneca Collaboration Products, and together with the AstraZeneca Lead Product, the AstraZeneca Products. The Company is responsible for advancing the AstraZeneca Lead Product through its phase 1 study, with the associated costs funded by AstraZeneca. The parties will collaborate thereafter to conduct a phase 2a study in asthma patients, with AstraZeneca continuing to fund development costs. After completion of a phase 2a study, Pieris has the option to co-develop the AstraZeneca Lead Product and

also has a separate option to co-commercialize the AstraZeneca Lead Product in the United States. For the AstraZeneca Collaboration Products, the Company will be responsible for the initial discovery of the novel Anticalin proteins, after which AstraZeneca will take the lead on continued development of the AstraZeneca Collaboration Products. The Company has the option to co-develop two of the four AstraZeneca Collaboration Products beginning at a pre-defined preclinical stage and would also have the option to co-commercialize these two programs in the United States, while AstraZeneca will be responsible for development and commercialization of the other programs worldwide.

The term of each of the AstraZeneca Agreements ends upon the expiration of all of AstraZeneca’s payment obligations under such agreement. The AstraZeneca Collaboration Agreement may be terminated by AstraZeneca in its entirety for convenience beginning 12 months after its effective date upon 90 days’ notice or, if the Company has obtained marketing approval for the marketing and sale of a product, upon 180 days’ notice. Each program may be terminated at AstraZeneca’s option; if any program is terminated by AstraZeneca, the Company will have full rights to such program. The AstraZeneca Collaboration Agreement may also be terminated by AstraZeneca or the Company for material breach upon 180 days’ notice of a material breach (or 30 days with respect to payment breach), provided that the applicable party has not cured such breach by the permitted cure period (including an additional 180 days if the breach is not susceptible to cure during the initial 180-day period) and dispute resolution procedures specified in the agreement have been followed. The AstraZeneca Collaboration Agreement may also be terminated due to the other party’s insolvency and may in certain instances be terminated on a product-by-product and/or country-by-country basis. Each party may also terminate an AstraZeneca Agreement if the other party challenges the validity of patents related to certain intellectual property licensed under such AstraZeneca Agreement, subject to certain exceptions for infringement suits, acquisitions and newly-acquired licenses. The AstraZeneca Platform License will terminate upon termination of the AstraZeneca Collaboration Agreement, on a product-by-product and/or country-by-country basis.

At inception, AstraZeneca is granted the following licenses: (i) research and development license for the AstraZeneca Lead Product, (ii) commercial license for the AstraZeneca Lead Product, (iii) individual research licenses for each of the four AstraZeneca Collaboration Products, (iv) individual commercial licenses for each of the four AstraZeneca Collaboration Products, and (v) individual non-exclusive platform technology licenses for the AstraZeneca Lead Product and the four AstraZeneca Collaboration Products. AstraZeneca will be granted individual development licenses for each of the four AstraZeneca Collaboration Products upon completion of the initial discovery of Anticalin proteins.

The collaboration will be managed on an overall basis by a Joint Steering Committee, or JSC, formed by an equal number of representatives from the Company and AstraZeneca. In addition to the JSC, the AstraZeneca Collaboration Agreement also requires each party to designate an alliance manager to facilitate communication and coordination of the parties' activities under the agreement, and further requires participation of both parties on a joint development committee, or JDC, and a commercialization committee. The responsibilities of these committees vary, depending on the stage of development and commercialization of each product.

Under the AstraZeneca Agreements, the Company received an upfront, non-refundable payment of $45.0 million. In addition, the Company will receive payments to conduct a phase 1 clinical study for the AstraZeneca Lead Product. The Company is also eligible to receive research, development, commercial, sales milestone payments, and royalty payments. The Company may receive tiered royalties on sales of potential products commercialized by AstraZeneca and for co-developed products, gross margin share on worldwide sales equal dependent on the Company’s level of committed investment.

The Company determined that the AstraZeneca Agreements should be combined and evaluated as a single arrangement under ASC 606 as they were executed on the same date. The arrangement with AstraZeneca, including the impact of any modifications, provides for the transfer of the following goods and services: (i) five non-exclusive platform technology licenses, (ii) research and development license for the AstraZeneca Lead Product, (iii) commercial license for the AstraZeneca Lead Product, (iv) development and manufacturing services for the AstraZeneca Lead Product (or the phase 1 services), (v) technology transfer services for the AstraZeneca Lead Product, (vi) research services related to the AstraZeneca Lead Product, (vii) participation on each of the committees, (viii) four research licenses for the AstraZeneca Collaboration Products, (ix) four commercial licenses for the AstraZeneca Collaboration Products, (x) research services for the AstraZeneca Collaboration Products and (xi) certain phase 2a services for the AstraZeneca Lead Product. Additionally, as the development licenses on the four AstraZeneca Collaboration Products may be granted at a discount in the future, the Company determined such discounts should be assessed as material rights at inception.

Management evaluated all of the promised goods or services within the contract and determined which such goods and services

were separate performance obligations. The Company determined that the licenses granted for the AstraZeneca Lead Product at the inception of the arrangement should be combined with the research services related to the AstraZeneca Lead Product and the licenses granted for the AstraZeneca Collaboration Products should be combined with the research services for the AstraZeneca Collaboration Products, as the licenses are not capable of being distinct. A third party would not be able to provide

the research and development services, due to the specific nature of the intellectual property and knowledge required to perform the services and AstraZeneca could not benefit from the licenses without the corresponding services. The Company also determined that each of the phase 1 services and the phase 2a services for the AstraZeneca Lead Product were distinct and that the participation on the various committees was also distinct as all of the phase 1 services, phase 2a services and the committee services could be performed by an outside party. The Company determined that the commercial licenses for the AstraZeneca Collaboration Products granted at the inception of the arrangement should be combined with the development licenses for the AstraZeneca Collaboration Products as the company would not benefit from the commercial license without the ability to develop each product.

As a result, management concluded that there were 16 performance obligations: (i) combined performance obligation comprised of a non-exclusive platform technology license, research and development license, and commercial licenses for the AstraZeneca Lead Product and research services for the AstraZeneca Lead Product, (ii) combined performance obligation comprised of development and manufacturing services, and technology transfer services for the AstraZeneca Lead Product, (iii) committee participation, (iv-vii) four combined performance obligations each comprised of a non-exclusive platform technology license, research licenses, and research services for each AstraZeneca Collaboration Product (viii-xi) four performance obligations comprised of a material right to acquire the development licenses granted for the AstraZeneca Collaboration Products, (xii-xv) four performance obligations comprised of the commercial licenses granted for the AstraZeneca Collaboration Products and (xvi) phase 2a services.

The Company allocated consideration to the performance obligations based on the relative proportion of their standalone selling prices. The Company developed standalone selling prices for licenses and corresponding research services by applying a risk adjusted, net present value, estimate of future potential cash flow approach, which included the cost of obtaining research services at arm’s length from a third-party provider, as well as internal full-time equivalent costs to support these services. The Company developed its standalone selling price for development and manufacturing services, and technology transfer services for the AstraZeneca Lead Product using estimated internal and external costs to be incurred.

The Company developed its standalone selling price for committee participation by using management’s estimate of the anticipated participation hours multiplied by a market rate for comparable participants.

The Company developed its standalone selling price for the commercial licenses and material rights granted on the development licenses by probability weighting multiple cash flow scenarios using the income approach.

The transaction price was comprised of fixed consideration of $45.0 million in upfront fees and variable consideration of (i) $14.2 million in estimated phase 1 services, (ii) $12.5 million in milestone payments achieved upon the initiation of a phase 1 study in December 2017, and (iii) $4.7 million in estimated phase 2a services. The $45.0 million upfront fee, which represents the fixed consideration in the transaction price, was allocated to each of the performance obligations based on the relative proportion of their standalone selling prices. Variable consideration of $14.2 million is related to the phase 1 services and will be allocated entirely to the performance obligation to which they relate. Variable consideration of $12.5 million related to the phase 1 trial milestone was allocated by relative selling price to the combined performance obligation comprised of a non-exclusive platform technology license, research and development license and commercial licenses for the AstraZeneca Lead Product and research services for the AstraZeneca Lead Product, and the combined performance obligation comprised of development and manufacturing services and technology transfer services for the AstraZeneca Lead Product performance obligations. Variable consideration of $4.7 million for phase 2a services was allocated specifically to the related performance obligation.

The amounts allocated to the license performance obligation for the AstraZeneca Lead Product and the four performance obligations for the four research licenses for AstraZeneca Collaboration Products will be recognized on a proportional performance basis as the activities are conducted over the life of the arrangement. The amounts allocated to the performance obligation for phase 1 services, technology transfer services for the AstraZeneca Lead Product will be recognized on a proportional performance basis over the estimated term of development through phase 2a study. The amounts allocated to the performance obligation for phase 2a services for the AstraZeneca Lead Product will be recognized on a proportionate performance basis over an estimated term of 12 months. The amounts allocated to the performance obligation for participation on each of the committees will be recognized on a straight-line basis over the expected term of development of the AstraZeneca Lead Product and the AstraZeneca Collaboration Products. The term of performance is approximately five years. The amounts allocated to the four performance obligations for the material rights to acquire a development license and the four performance obligations for commercial licenses for the AstraZeneca Collaboration Products will be recognized upon exercise of the specific material right and delivery of each of the development licenses. As of December 31, 2021, there was $18.7 million of aggregate transaction price allocated to remaining performance obligations.

Additionally, the Company evaluated payments required to be made between both parties as a result of the shared development costs of the AstraZeneca Lead Product and the two AstraZeneca Collaboration Products for which the Company has a co-development option. The Company will classify payments made as a reduction of revenue and will classify payments received as revenue, in the period they are earned.

Under the AstraZeneca Agreements, the Company is eligible to receive various research, development, commercial and sales milestones. There is uncertainty that the events to obtain the research and development milestones will be achieved given the nature of clinical development and the stage of the Company’s technology. The Company has thus determined that all research and development milestones, other than the phase 1 initiation milestone achieved in December 2017 and included in the impact of adoption of ASC 606, will be constrained until it is deemed probable that a significant revenue reversal will not occur.

On March 29, 2021, the Company and AstraZeneca entered into (1) Amendment No. 1 to the Non-exclusive Anticalin® Platform License Agreement dated May 2, 2017 and (2) Amendment No. 2 to the License and Collaboration Agreement dated May 2, 2017, as previously amended by Amendment No. 1 dated September 14, 2020, collectively, the Amended Collaboration Agreement. Under the Amended Collaboration Agreement, the parties agreed to restructure certain commercial economics for the PRS-060/AZD1402 program by increasing potential sales milestones and reducing potential sales royalties, while fundamentally maintaining the overall value split between AstraZeneca and the Company.

In connection with the Amended Collaboration Agreement, the Company and AstraZeneca entered into a Subscription Agreement pursuant to which the Company agreed to issue to AstraZeneca, and AstraZeneca agreed to acquire from the Company, 3,584,230 shares of the Company’s common stock for a total purchase price of $10.0 million, or $2.79 per share, in a private placement transaction pursuant to Section 4(a)(2) of the Securities Act of 1933, as amended. The Subscription Agreement closed on April 1, 2021 and includes a requirement that the Company file a registration statement to register the resale of the shares issued to AstraZeneca within 60 calendar days of the issuance of the shares. The Company assessed the payment under ASC 606 and concluded that the fair value of the shares on a per share basis was $2.60 per share as of the transaction date. This resulted in a premium paid for the shares of $0.7 million, which was added to the deferred revenue balance and will be recognized over time in line with our revenue recognition pattern for all remaining performance obligations.

Also in March 2021, the Company earned a $13.0 million milestone from AstraZeneca related to the initiation of the phase 2a study for PRS-060/AZD1402. The Company assessed the milestone payment under ASC 606 and determined that there no longer existed a constraint on the milestone as the performance obligation related to the phase 2a study was fully satisfied. Therefore, the Company realized the full $13.0 million as milestone revenue for the year ended December 31, 2021.

In January 2022, the Company and AstraZeneca jointly discontinued one discovery-stage programs as they were not able to validate an exploratory target. Pieris retains co-development and co-commercialization options for two of the three remaining active discovery programs.

As of December 31, 2021, there is $0.9 million and $17.0 million of current and non-current deferred revenue, respectively, related to the AstraZeneca Agreements.

The Company incurred $1.6 million of third-party success fees to obtain the contract with AstraZeneca. Upon adoption of ASC 606, the Company capitalized $1.1 million in accordance with ASC 340. As of December 31, 2021, the remaining balance of the asset recognized from transaction costs to obtain the AstraZeneca contract is $0.6 million. Amortization during the years ended December 31, 2021 and 2020 was de minimis.

Servier

On January 4, 2017, the Company entered into a license and collaboration agreement, or Servier Collaboration Agreement, and a non-exclusive Anticalin platform license agreement, or Servier Platform License, and together with the Servier Collaboration Agreement, the Servier Agreements with Les Laboratoires Servier and Institut de Recherches Internationales Servier, or Servier, pursuant to which the Company and Servier agreed to initially pursue five bispecific therapeutic programs.

Five committed programs were initially defined, which may combine antibodies from the Servier portfolio with one or more Anticalin proteins based on the Company’s proprietary platform to generate innovative IO bispecific drug candidates, or the Collaboration Products. The collaboration may be expanded by up to three additional therapeutic programs. The Company had the option to co-develop and retain commercial rights in the United States for PRS-332, the initial lead program under the collaboration, or the Initial Lead, and has a similar option on up to three additional programs, or the Co-Development Collaboration Products, while Servier will be responsible for development and commercialization of the other programs worldwide, or the Servier Worldwide Collaboration Products. Each party is responsible for an agreed upon percentage of shared costs, as set forth in the budget for the collaboration plan, and as further discussed below.

The Co-Development Collaboration Products may be jointly developed, according to a collaboration plan, through marketing approval from the U.S. Food and Drug Administration or the European Medicines Agency. Servier Worldwide Collaboration Products may be jointly developed, according to a collaboration plan, through specified preclinical activities, at which point Servier becomes responsible for further development of the Collaboration Product.

At inception, Servier was granted the following licenses: (i) development license for the Initial Lead, (ii) commercial license for the Initial Lead, (iii) individual research licenses for each of the four Collaboration Products, and (iv) individual non-exclusive platform technology licenses for the Initial Lead and for each of the four Collaboration Products. Upon achievement of certain development activities, specified by the collaboration for each Servier Agreement, Servier will be granted a development license and a commercial license. For the Initial Lead and the Co-Development Collaboration Products, the licenses granted are with respect to the entire world except for the United States. For Servier Worldwide Collaboration Products, the licenses granted are with respect to the entire world.

The Servier Agreements are managed on an overall basis by a joint executive committee, or JEC, formed by an equal number of members from the Company and Servier. Decisions by the JEC will be made by consensus; however, in the event of a disagreement, each party will have final-decision making authority as it relates to the applicable territory in which such party has commercialization rights for the applicable product. In addition to the JEC, the Servier Collaboration Agreement requires the participation of both parties on: (i) a JSC, (ii) a JDC, (iii) a joint intellectual property committee, or JIPC, and (iv) a joint research committee, or JRC. The responsibilities of these committees vary, depending on the stage of development and commercialization of the Collaboration Products.

For the Initial Lead and Co-Development Collaboration Products, the Company and Servier are responsible for an agreed upon percent of the shared costs required to develop the products through commercialization. In the event that the Company fails to exercise its option to co-develop the Co-Development Collaboration Products, Servier has the right to continue with the development and will be responsible for all costs required to develop the products through commercialization.

Under the Servier Agreements, the Company received an upfront, non-refundable payment of €30.0 million (approximately $32.0 million). In addition, the Company is eligible to receive research, development, commercial, and sales milestone payments as well as tiered royalties up to low double digits on the sales of commercialized products in the Servier territories. Since inception of the Servier Collaboration Agreement, the Company has achieved four development milestones under Servier Agreements totaling €3.8 million (approximately $4.3 million), all of which became billable on their respective achievement dates.

The initial research collaboration term, as it relates to the Initial Lead and Collaboration Products, shall continue for three years from the effective date of the Servier agreements, and may be mutually extended for two one-year terms consecutively applied.

The term of each Servier Agreement ends upon the expiration of all of Servier’s payment obligations under such Servier Agreement. The Servier Agreements may be terminated by Servier for convenience beginning 12 months after their effective date upon 180 days’ notice. The Servier Agreements may also be terminated by Servier or the Company for material breach upon 90 days’ or 120 days’ notice under the Servier Collaboration Agreement and the Servier Platform License, respectively, provided that the applicable party has not cured such breach by the applicable 90-day or 120-day permitted cure period, and dispute resolution procedures specified in the applicable Servier Agreement have been followed. The Servier Agreements may also be terminated due to the other party’s insolvency or for a safety issue and may in certain instances be terminated on a product-by-product and/or country-by-country basis. The Servier Platform License will terminate upon termination of the Servier Collaboration Agreement, on a product-by-product and/or country-by-country basis. In February 2020, the research term was extended for 12 months. The research term was then extended for another 12 months in February 2021.

As the Company and Servier are considered to be active participants in the Servier Agreements and are exposed to significant risks and rewards, certain units of account within the Servier Agreements are within the scope of ASC 808. The arrangement with Servier provides for the transfer of the following goods and services: (i) five non-exclusive platform technology licenses, a development license, a commercial license and research and development services for the Initial Lead, (ii) participation on each of the committees, (iii) four research licenses for Collaboration Products, and (iv) research and development services for the Collaboration Products. Additionally, as the development and commercial licenses on the four Collaboration Products may be granted at a discount in the future, the Company determined such discounts should be assessed as material rights at inception.

Management evaluated all of the promised goods or services within the contract and determined which goods and services

were separate performance obligations. The Company determined that the licenses granted at the inception of the Servier collaboration, should be combined with the research and development services to be provided for the Initial Lead and

Collaboration Products, over the term of the Servier Agreements, as such licenses are not capable of being distinct. A third party would not be able to provide the research and development services, due to the specific nature of the intellectual property and knowledge required to perform the services, and Servier could not benefit from the licenses without the corresponding services. The Company determined that the participation on the various committees was distinct as the services could be performed by an outside party.

As a result, management concluded that there are 10 performance obligations at the inception of the Servier Agreements. The following performance obligations are within the scope of ASC 808: (i) combined performance obligation comprised of a non-exclusive platform technology license, commercial license, development license and research and development services for the Initial Lead, (ii) two separate performance obligations each comprised of a combined non-exclusive platform technology license, research license, and research and development services for each Co-Development Collaboration Product (iii) one performance obligation comprised of participation in the various governance committees, and (iv) two combined performance obligations comprised of the development and commercial licenses granted for the Co-Development Collaboration Products (and corresponding discounts) upon the achievement of specified preclinical activities, resulting in material rights. Revenue recognized associated with these performance obligations are presented as Collaboration Revenue within the Statement of Operations. The following performance obligations are within the scope of ASC 606: (i) two separate performance obligations each comprised of a combined non-exclusive platform technology license, research license and research and development services for each Servier Worldwide Collaboration Product, and (ii) two combined performance obligations comprised of the development and commercial licenses granted for the Servier Worldwide Collaboration Products (and corresponding discounts) upon the achievement of specified preclinical activities, resulting in material rights. Revenue recognized associated with these performance obligations are presented as Customer Revenue within the Statement of Operations.

The Company allocated consideration to the performance obligations based on the relative proportion of their standalone selling prices. The Company developed its standalone selling prices for licenses by applying a risk adjusted, net present value, estimate of future potential cash flows approach, which included the cost of obtaining research and development services at arm’s length from a third-party provider, as well as internal full-time equivalent costs to support these services.

The Company developed its estimate of standalone selling price for committee participation by using management’s estimate of the anticipated participation hours multiplied by a market rate for comparable participants.

The Company developed its estimate of standalone selling price for the material rights granted on the development and commercial licenses granted for the Collaboration Products by probability weighting multiple cash flow scenarios using the income approach.

The transaction price at inception is comprised of the fixed upfront fee of €30.0 million (approximately $32.0 million) and was allocated to the performance obligations based on the relative proportion of their standalone selling prices.

The amounts allocated to the performance obligation for the Initial Lead and the four performance obligations for the four research and development licenses for Collaboration Products will be recognized on a proportional performance basis as the activities are conducted over the life of the arrangement. The term of the performance at inception of the Servier Agreements for the Initial Lead and each of the Co-Development Collaboration Products may be through approval of certain regulatory bodies; a period which could be many years. The term of the performance for each of the other two Servier Worldwide Collaboration Products is through the initial research and collaboration term, plus potential extensions. The amounts allocated to the performance obligation for participation on each of the committees will be recognized on a straight-line basis over the anticipated performance period over the entirety of the arrangement with Servier. The amounts allocated to the four performance obligations for the material rights to acquire development and commercial licenses for the Co-Development Collaboration Products are granted in the future will be recognized over time upon delivery of each of the licenses through marketing approval. The amounts allocated to the four performance obligations for the material rights to acquire development and commercial licenses for the Servier Developed Collaboration Products are granted in the future will be recognized upon delivery of each of the licenses. As of December 31, 2021, there was $10.4 million of aggregate transaction price allocated to remaining performance obligations.

Additionally, the Company evaluated payments required to be made between both parties as a result of the shared development costs of the Initial Lead and Collaboration Products. The Company will classify payments made as a reduction of revenue and will classify payments received as revenue, in the period they are earned.

Under the Servier Agreements the Company is eligible to receive various research, development, commercial, and sales milestones. There is uncertainty that the events to obtain the research and development milestones will be achieved given the

nature of clinical development and the stage of the Company’s technology. The Company has thus determined that all research and development milestones will be constrained until it is deemed probable that a significant revenue reversal will not occur.

In September 2019, Servier notified the Company of its decision to discontinue co-development of PRS-332, a PD-1-LAG-3 bispecific that served as the initial development program under the Pieris-Servier alliance, for strategic reasons. The Company does not presently intend to continue development of PRS-332 but retains full rights to advance the development and commercialization of the product on a world-wide basis in the future.

In February 2020, the research term was extended for 12 months. The Company updated the transaction price for the extension for revenue recognition purposes and allocated it ratably over all unsatisfied performance obligations. As part of the expiration of the initial research term, the option to expand the collaboration beyond the initial five committed programs also expired. In March 2020, Servier notified the Company of its decision to discontinue co-development of two earlier preclinical stage programs for strategic reasons based upon an extensive portfolio review. The notification required a 60-day period to complete remaining obligations on the programs; however, the Company determined that the material rights to acquire development and commercial licenses for one Co-Development Collaboration Product and for one Servier Developed Collaboration Products lapsed in March 2020 and recognized $7.1 million of previously deferred revenue associated with these material rights during 2020. The discontinuation of the two earlier preclinical stage programs decreased the future potential milestone payments the Company could achieve. The parties continue to advance the development of two preclinical programs: PRS-344/S095012, a 4-1BB/PD-L1 bispecific designed as a co-development program, and PRS-352, which addresses undisclosed targets and for which Servier has worldwide rights.

In February 2021, the research term was extended for another 12 months.

As of December 31, 2021, there is $5.8 million and $4.6 million of current and non-current deferred revenue, respectively, related to the Servier Agreements.

The Company incurred costs to obtain the contract with Servier. Upon adoption of ASC 606, the Company capitalized $0.5 million of third-party service fees in accordance with ASC 340. As of December 31, 2021, the remaining balance of the asset recognized from costs to obtain the Servier contract is $0.1 million. Amortization during the twelve months ended December 31, 2021 was de minimis. Amortization during the twelve months ended December 31, 2020 was $0.1 million.

Contract Balances

The Company receives payments from its collaboration partners based on payments established in each contract. Upfront payments and fees are recorded as deferred revenue upon receipt or when due until such time as the Company satisfies its performance obligations under each arrangement. A contract asset is a conditional right to consideration in exchange for goods or services that the Company has transferred to a customer. Amounts are recorded as accounts receivable when the Company’s right is unconditional.

There were $31.6 million of additions to deferred revenue during the twelve months ended December 31, 2021 and reductions to deferred revenue were $11.0 million for the twelve months ended December 31, 2021.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-URI http://asc.fasb.org/topic&trid=49130388

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130551-203045

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130556-203045

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130550-203045

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130558-203045

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130554-203045

+ Details

Collaboration agreements	12 Months Ended
Collaboration agreements	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Collaboration agreements	Collaboration agreements In August 2020, the Company entered into a Clinical Trial Collaboration and Supply Agreement, or the Lilly Agreement, with Eli Lilly and Company, or Lilly, pursuant to which the Company and Lilly will collaborate on a phase 2 clinical study, or the Study, to determine the safety and efficacy of the Company's cinrebafusp alfa in combination with the standard of care regimen for the second-line treatment of advanced or metastatic gastric cancer, ramucirumab (CYRAMZA®) and paclitaxel for the second-line treatment of HER2+ gastric cancer. Under the terms of the non-exclusive Lilly Agreement, the Company will sponsor the Study and Lilly will supply the Company with ramucirumab as well as provide input on certain clinical and regulatory aspects of the Study in exchange for jointly owning clinical data and inventions relating to the combination regimen that may arise from the Study. Any material changes to the protocol for the Study, and any changes relating to ramucirumab, will require Lilly’s prior written consent, which shall not be unreasonably withheld, conditioned or delayed. The Lilly Agreement will expire upon completion of the parties’ contractual obligations. The Lilly Agreement may also be terminated (a) by either party for an uncured material breach by the other party upon 60 days’ notice, subject to a reasonable extension if such material breach requires more than 60 days to cure; (b) by either party in the event that the Study unreasonably affects patient safety, provided that the terminating party promptly notifies the other party and the other party is given the opportunity to propose modifications to the Study to address the safety issues; (c) by either party, following 15 days’ written notice, if regulatory action is taken preventing the terminating party from providing its compound or if the terminating party decides to discontinue development of its compound; (d) by either party, immediately upon written notice to the other party for breach by the other party of its material obligations under certain sections of the Lilly Agreement, or breach of certain of the other party's representations and warranties; and (e) by Lilly in the event of certain safety concerns related to the use of ramucirumab in the Study. The Company concluded that the Lilly Agreement is within the scope of ASC 808, which defines collaborative arrangements and addresses the presentation of the transactions between the two parties in the income statement and related disclosures. However, ASC 808 does not provide guidance on the recognition of consideration exchanged or accounting for the obligations that may arise between the parties. The Company has concluded that ASC 730, Research and Development, should be applied by analogy. There is no financial statement impact for the Lilly Agreement as the value of the drug supply received from Lilly is offset against the drug supply cost.

Grant Income	12 Months Ended
Grant Income	Dec. 31, 2021
Receivables [Abstract]
Grant Income	Grant Income One of the Company's proprietary respiratory assets is PRS-220, an oral inhaled Anticalin protein targeting connective tissue growth factor, or CTGF, and it is being developed as a local treatment for idiopathic pulmonary fibrosis. In June 2021, the Company received a €14.2 million (approximately $17.0 million) grant from the Bavarian Ministry of Economic Affairs, Regional Development and Energy (the Bavarian Grant) supporting research and development for post-acute sequelae of SARS-CoV-2 infection (PASC) pulmonary fibrosis, or PASC-PF, also known as post-COVID-19 syndrome pulmonary fibrosis, or “long COVID”. The Bavarian Grant provides partial reimbursement for qualifying research and development activities on PRS-220, including drug manufacturing costs, activities and costs to support an IND filing, and phase 1 clinical trials costs. The Bavarian Grant provides reimbursement of qualifying costs incurred through August 2023, which follows the expected development timeline of this program. Qualifying costs incurred may exceed the annual grant funding thresholds. If the Company receives any proceeds from the sale of or licensing income from PRS-220, the funds available for reimbursement will be reduced proportionally if they are obtained prior to August 2023. The Company is required to communicate such proceeds in each case with the request to draw-down the funds.

Cash, Cash Equivalents and Investments	12 Months Ended
Cash, Cash Equivalents and Investments	Dec. 31, 2021
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents and Investments	Cash, Cash Equivalents and Investments As of December 31, 2021 and 2020, cash equivalents were $56.9 million and $64.0 million, respectively, and are comprised of money market accounts, all of which are Level 1 investments. The Company did not hold any Level 2 or 3 investments as of December 31, 2021 and 2020 and did not have any transfers of investments between levels during the years ended December 31, 2021 and 2020. The Company did not have any realized gains or losses for the year ended December 31, 2021. The Company had $0.6 million of realized losses for the year ended December 31, 2020.

Property and Equipment, Net

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Property and Equipment, Net

Property and equipment are summarized as follows (in thousands):


	Years Ended December 31,
	2021		2020
Leasehold improvements	$	13,130	$	14,159
Laboratory equipment	11,354		11,188
Office furniture and equipment	1,959		2,120
Computer equipment	396		394
Property and equipment at cost	26,839		27,861
Accumulated depreciation	(7,717)		(5,815)
Property and equipment, net	$	19,122	$	22,046

Depreciation expense was $2.4 million and $2.1 million for the years ended December 31, 2021 and 2020, respectively. There were no other changes in accumulated depreciation other than the foreign currency impact.

Accrued Expenses

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Accrued Expenses

Accrued expenses and other current liabilities consisted of the following (in thousands):


	Years Ended December 31,
	2021		2020
Research and development fees	$	5,682	$	2,001
Compensation expense	3,581		2,759
Accrued accounts payable	2,980		1,220
Collaboration cost-sharing obligation	1,610		16
Accrued license obligations	1,541		358
Lease liabilities	1,049		1,030

Other current liabilities	393		347
Total	$	16,836	$	7,731

Income Taxes

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Income Taxes

The Company reported a loss before income taxes consisting of the following (in thousands):


	Years Ended December 31,
	2021		2020
Domestic	$	(11,312)	$	(12,134)
Foreign	(34,426)		(24,932)
Loss before income taxes	$	(45,738)	$	(37,066)

The components of the provision for income taxes are as follows (in thousands):


	Years Ended December 31,
	2021		2020
Current:
Federal	$	—	$	—
State	—		—
Foreign	—		164
Total current	—		164
Deferred:
Federal	—		—
State	—		—
Foreign	—		—
Total deferred	—		—
Provision for income taxes	$	—	$	164

The reconciliation of the federal statutory rate to the Company’s effective tax rate is as follows:


	2021		2020
Federal income tax rate	21.0	%	21.0	%

Foreign rate differential	5.6		1.9
State tax, net of federal benefit	1.2		1.9
US tax on foreign income	—		—
Share-based awards compensation	(3.5)		(3.8)
Permanent items	(0.2)		(2.4)
Provision to return	3.3		—
Other	—		(0.4)

Change in valuation allowance	(27.4)		(18.7)
Effective income tax rate	—	%	(0.5)	%

The components of deferred tax assets and liabilities related to net tax effects of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for income taxes purposes were as follows (in thousands):


	Years Ended December 31,
	2021		2020
Deferred tax assets:
Net operating loss carryforwards	$	49,280	$	39,175
Share-based awards compensation	2,739		2,913
Accrued expenses	323		230
Depreciation and other	384		297

Unrealized foreign currency	256		771
Lease liability	4,022		4,582
Total deferred tax assets	57,004		47,968
Deferred tax liabilities:
Right-of-use asset	(3,729)		(4,235)

Accrued expenses	(68)		—
Total deferred tax liabilities	(3,797)		(4,235)
Less: valuation allowance:	(53,207)		(43,733)
Net deferred tax asset	$	—	$	—

The Company operates in multiple jurisdictions. Accordingly, the Company files U.S. federal and state income tax returns as well as returns in multiple foreign jurisdictions. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income, and tax-planning strategies in making this assessment. Management believes it is more likely than not that the results of future operations will not generate sufficient taxable income in the United States or in its foreign jurisdictions to realize the full benefits of its deferred tax assets. As of December 31, 2021, the Company continues to maintain a full valuation allowance against all net deferred tax assets.

The cumulative amount of earnings of our foreign subsidiaries are expected to be permanently invested in the foreign subsidiaries. Deferred taxes have not been provided on the excess of book basis over tax basis, or the excess tax basis over book basis in the shares of our foreign subsidiaries because these basis differences are not expected to reverse in the foreseeable future and are essentially permanent in duration. Our intention is to reinvest the earnings of the foreign subsidiaries indefinitely.

The increase in the valuation allowance of deferred tax assets of $9.5 million was primarily a result of the operating losses generated in current tax year.

As of December 31, 2021, the Company had net operating loss carryforwards for U.S. federal income tax purposes of $33.1 million and net operating loss carryforwards for state income tax purposes of $37.4 million. Federal tax loss carryforwards that were created prior to December 31, 2017 expire through 2037 and federal losses created after that date do not expire. State loss carryforwards expire starting in 2035. Pursuant to Section 382 of the Internal Revenue Code, and similar state tax law, certain substantial changes in the Company’s ownership may result in a limitation on the amount of net operating loss and tax credit carryforwards that may be used in future years. Utilization of the net operating loss and tax credit carryforwards may be subject to an annual limitation under Section 382 of the Internal Revenue Code of 1986 due to ownership change limitations that have occurred previously or that could occur in the future. These ownership changes may limit the amount of net operating loss and tax credit carryforwards that can be utilized annually to offset future taxable income and tax, respectively. The Company completed a Section 382 study through December 31, 2020. Based on the study, the Company underwent an ownership change for Section 382 purposes which occurred in February 2018. As a result of the ownership change, the Company’s net operating loss and tax credit carryforwards as of the ownership change dates are subject to limitation under Section 382; however, these limitations are not expected to result in any of the impacted net operating loss and tax credit carryforwards to expire unutilized. Any net operating losses or tax credits generated after the February 2018 change are not subject to this annual limitation. However, subsequent ownership changes, as defined by Section 382, may potentially further limit the amount of net operating loss and tax credit carryforwards that could be utilized to offset future taxable income and tax. The Company is currently open to examination under the statute of limitations by the Internal Revenue Service and state jurisdictions for the tax years ended

2016 through the current year. Carryforward tax attributes generated in years past may still be adjusted upon future examination if they have or will be used in a future period. The Company is currently under examination in Germany for 2014 through 2017; however, the Company is not under examination by the Internal Revenue Service or any other jurisdictions for any tax years.

As of December 31, 2021, the Company had German corporate income tax and trade tax net operating loss carryforwards of approximately $154.8 million and $153.9 million respectively. Under current German laws, tax loss carryforwards may only be used to offset any relevant later assessment period (calendar year) of $1.2 million plus 60% of the exceeding taxable income and trade profit of such period and do not expire. In addition, certain transactions, including transfers of shares or interest in the loss holding entity, may result in the partial or total forfeiture of tax losses existing at that date. Partial or total forfeiture of tax losses may further occur in corporate reorganizations of the loss holding entity.

The Company accounts for uncertain tax positions pursuant to ASC 740, Income Taxes, which prescribes a recognition threshold and measurement process for financial statement recognition of uncertain tax positions taken or expected to be taken in a tax return. If the tax position meets this threshold, the benefit to be recognized is measured at the largest amount of benefit that is more likely than not (determined by cumulative probability) of being realized upon ultimate settlement with the taxing authority. The Company recorded an uncertain tax position related to a prior year position, that if successfully challenged by tax authorities could result in the loss of certain tax attributes. The balance of uncertain tax positions will remain until such time that settlement is reached with the relevant tax authorities or should the statute of limitations expire. The Company recognizes interest and penalties, if any, related to uncertain tax positions in income tax expense. No interest and penalties related to uncertain tax positions were accrued at December 31, 2021 and December 31, 2020.

The following table sets forth a reconciliation of the beginning and ending amounts of unrecognized tax benefits, excluding the impact of interest and penalties, for the years ended December 31, 2021 (in thousands):


Unrecognized tax benefits at December 31, 2020	$	6,135
Currency translation adjustment	(470)
Unrecognized tax benefits at December 31, 2021	$	5,665

The Company does not expect unrecognized tax benefits to change significantly over the next 12 months. The full amount of unrecognized tax benefits would impact the effective rate, subject to valuation allowance considerations, if recognized.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

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+ Details

Stockholders' equity	12 Months Ended
Stockholders' equity	Dec. 31, 2021
Equity [Abstract]
Stockholders' equity	Stockholders’ equity The Company had 300,000,000 shares authorized and 72,222,661 and 56,002,815 shares of common stock issued and outstanding as of December 31, 2021 and December 31, 2020, respectively, with a par value of $0.001 per share. The Company had 10,000,000 shares authorized and 15,617 shares of preferred stock issued and outstanding as of December 31, 2021. The Company had 10,000,000 shares authorized and 14,429 shares of preferred stock issued and outstanding as of December 31, 2020. Preferred stock has a par value of $0.001 per share, and consists of the following tranches: •Series A Convertible, 85 and 2,907 shares issued and outstanding at December 31, 2021 and December 31, 2020, respectively. •Series B Convertible, 4,026 and 5,000 shares issued and outstanding at December 31, 2021 and December 31, 2020, respectively. •Series C Convertible, 3,506 and 3,522 shares issued and outstanding at December 31, 2021 and December 31, 2020, respectively. •Series D Convertible, 3,000 shares issued and outstanding at both December 31, 2021 and December 31, 2020. •Series E Convertible, 5,000 and zero shares issued and outstanding at December 31, 2021 and December 31, 2020, respectively. Common Stock Each share of the Company’s common stock is entitled to one vote and all shares rank equally as to voting and other matters. Dividends may be declared and paid on the common stock from funds legally available therefor, if, as and when determined by the Board of Directors. Preferred Stock The Company has issued multiple series (Series A through E) of preferred stock to certain entities affiliated with Biotechnology Value Fund, L.P., or BVF. In each case, each share Preferred Stock is convertible into 1,000 shares of the Company's common stock (subject to adjustment as provided in the Certificate of Designation for each series) at any time at the option of the holder, provided that the holder is prohibited from converting the Preferred Stock into shares of the Company's common stock if, as a result of such conversion, the holder, together with its affiliates, would own more than 9.99% of the total number of shares of Common Stock then issued and outstanding, or the Beneficial Ownership Limitation. The holder may reset the Beneficial Ownership Limitation to a higher or lower number, not to exceed 19.99% of the total number of common shares issued and outstanding immediately after giving effect to a conversion, upon providing written notice to the Company. Any such notice providing for an increase to the Beneficial Ownership Limitation will be effective 61 days after delivery to the Company. Series A, Series B, Series C, Series D and Series E Preferred Stock rank senior to the Company’s common stock; senior to any class or series of capital stock of the Company created after the designation of and specifically ranking by its terms as junior to the five series of Preferred Stock; in parity with each other and with any class or series of capital stock of the Company created after the designation of and specifically ranking by its terms as in parity with the existing five series of Preferred Stock; and junior to any class or series of capital stock of the Company created after the designation of and specifically ranking by its terms as senior to the existing five series of Preferred Stock. In the event of the Company’s liquidation, dissolution or winding up, subject to the rights of holders of, holders are entitled to receive a payment equal to $0.001 per share of Preferred Stock pursuant to the rights and preferences discussed above, plus an additional amount equal to any dividends declared but unpaid on such shares. However, if the assets of the Company are insufficient to comply with the preceding sentence, then all remaining assets of the Company shall be distributed ratably to holders of the shares of the existing five series of Preferred Stock. For each series of Preferred Stock, the Company designated the requisite number of shares of its authorized and unissued preferred stock as a specific series of Preferred Stock and filed a Certificate of Designation with the Nevada Secretary of State. Shares of Preferred Stock generally have no voting rights, except as required by law and except that the consent of holders of a majority of the then outstanding Preferred Stock is required to amend the terms of the Certificate of Designation for each respective series of Preferred Stock. Holders of Preferred Stock are entitled to receive any dividends payable to holders of the Company's common stock subject to the rights and preferences discussed above, in each case, as to distributions of assets upon the Company’s liquidation, dissolution or winding up whether voluntarily or involuntarily and/or the right to receive dividends. Series A Preferred Stock In June 2016, the Company entered into a securities purchase agreement for a private placement of the Company’s securities with a select group of institutional investors, or the 2016 PIPE. The 2016 PIPE sale transaction, by the Company, consisted of 8,188,804 units at a price of $2.015 per unit for gross proceeds, to the Company, of approximately $16.5 million. After deducting for placement agent fees and offering expenses, the aggregate net proceeds from the private placement was approximately $15.3 million. In connection with the 2016 PIPE, the Company issued 3,225,804 shares of common stock and 4,963 shares of Series A Preferred Stock to the 2016 PIPE investors. Series B Preferred Stock On January 30, 2019, the Company and certain entities affiliated with Biotechnology Value Fund, L.P., or BVF entered into an exchange agreement pursuant to which BVF agreed to exchange an aggregate of 5,000,000 shares of the Company’s common stock owned by BVF for an aggregate of 5,000 shares of Series B Preferred Stock. Series C and 2019 Private Placement In November 2019, the Company entered into a securities purchase agreement for a private placement, or the Purchase Agreement with a select group of institutional investors, including lead investor BVF as well as existing and new investors, or Investors. The private placement consisted of 9,014,960 units, at a price of $3.55 per unit, or the Financing, for gross proceeds of approximately $32.0 million, and net proceeds to the Company of approximately $31.0 million. Each unit consists of (i) one share of the Company’s common stock, or Common Shares, or 0.001 shares of non-voting Series C convertible preferred stock, or Series C Preferred Shares, and together with the Common Shares, or Shares, and (ii) one immediately-exercisable warrant to purchase one share of the Company’s common stock with an exercise price of $7.10, or Exercise Price. If (i) the initial public disclosure of the phase 2a Study of PRS-060/AZD1402 that includes the “p” value achieved for the primary endpoint of such study reveals top-line data on the primary efficacy endpoint in the phase 2a Study with a “p” value below 0.05 (i.e., p < 0.05) in at least one dose level; and (ii) the 10-day volume weighted average stock price commencing on the trading day immediately after the initial public disclosure is at least three percent more than the Exercise Price, ((i) and (ii), collectively, the “Performance Condition”), then the warrants will be exercisable for a period of 60 days from the date of the initial data disclosure and may only be exercised for cash. Otherwise, the warrants will be exercisable for a period of five years from the date of issuance, or Exercise Date. If the Performance Condition has not been met and the last reported sale price of the Company’s common stock immediately prior to the Expiration Date was greater than the Exercise Price, then the warrants shall be automatically deemed exercised on a cashless basis on the Expiration Date. Upon issuance, each Series C Preferred Share included an embedded beneficial conversion feature as the market price of the Company’s Common Stock on the date of issuance of the Series C convertible preferred stock was $3.43 per share. As a result, the Company recorded the intrinsic value of the beneficial conversion feature of $2.8 million as a discount on the Series C convertible preferred stock at issuance. As the Series C Preferred Shares are immediately convertible upon issuance and do not include a stated redemption date, the discount was immediately accreted as a deemed dividend. Series D Preferred Stock Conversion On March 31, 2020, the Company and certain entities affiliated with BVF entered into an exchange agreement pursuant to which, on April 1, 2020, BVF exchanged an aggregate of 3,000,000 shares of the Company’s common stock owned by BVF for an aggregate of 3,000 shares of Series D Preferred Stock. Series E Preferred Stock Conversion On May 20, 2021, the Company and certain entities affiliated with BVF entered into an exchange agreement pursuant to which, BVF exchanged an aggregate of 5,000,000 shares of the Company’s common stock owned by BVF for an aggregate of 5,000 shares of Series E Preferred Stock. Open Market Sales Agreement In August 2019, the Company entered into a sales agreement with Jefferies LLC pursuant to which the Company may offer and sell shares of its common stock, from time to time, up to an aggregate gross sales proceeds of $50.0 million (the 2019 ATM Program). In August 2021, the Company established a second ATM offering program, or the 2021 ATM Program, under the existing sales agreement with Jefferies LLC, pursuant to which the Company may offer and sell shares of its common stock, par value $0.001 per share, from time to time, up to an aggregate amount of gross sales proceeds of $50.0 million. The 2021 ATM Program is offered under a shelf registration statement on Form S-3 that was filed with and declared effective by the SEC in August 2021. For the year ended December 31, 2021, the Company sold 8.2 million shares for gross proceeds of $39.7 million under both ATM programs at an average stock price of $4.85. For the year ended December 31, 2020, the Company sold 3.6 million shares at a price of $2.80 per share resulting in gross proceeds of $10.0 million under the 2019 ATM Program only, which expired in August 2021.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

Net Loss per Share	12 Months Ended
Net Loss per Share	Dec. 31, 2021
Earnings Per Share [Abstract]
Net Loss per Share	Net Loss per Share Basic net loss per share is calculated by dividing net income (loss) by the weighted average shares outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share is calculated by adjusting weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock and if-converted methods. For purposes of the diluted net loss per share calculation, preferred stock, stock options, and warrants are considered to be common stock equivalents but have been excluded from the calculation of diluted net loss per share, as their effect would be anti-dilutive for all periods presented. Therefore, basic and diluted net loss per share were the same for all periods presented. For the years ended December 31, 2021 and 2020, and as calculated using the treasury stock method, approximately 36.8 million and 37.0 million of weighted average shares, respectively, were excluded from the calculation of diluted weighted average shares outstanding as their effect was antidilutive.

Stock and Employee Benefit Plans

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Stock and Employee Benefit Plans

Employee, Director and Consultant Equity Incentive Plans

At the Annual Shareholder Meeting, held on June 23, 2020, the shareholders approved the 2020 Employee, Director and Consultant Equity Incentive Plan, or the 2020 Plan. The 2020 Plan originally permitted the Company to issue up to 3,500,000 shares of common stock pursuant to awards granted under the 2020 Plan. Upon approval of the 2020 Plan, the

2019 Employee, Director and Consultant Equity Incentive Plan, or the 2019 Plan, was terminated; all unissued options were canceled and no additional awards will be made thereunder. All outstanding awards under the 2019 Plan will remain in effect and any awards forfeited from the outstanding awards will be allocated back into the 2020 Plan. The 2020 Plan, similar to the 2019 Plan, provided for the grant of stock options, restricted and unrestricted stock awards, and other stock-based awards to employees of the Company, non-employee directors of the Company, and certain other consultants performing services for the Company as designated by either the Board of Directors or the compensation committee of the Board of Directors. At the 2021 Annual Meeting of Stockholders, held on June 25, 2021, the Company’s stockholders approved the first amendment to the 2020 Plan to add 2,250,000 shares for issuance under the 2020 Plan, which increased the total permitted for issuance under the 2020 Plan to 5,750,000.

There were approximately 1,579,678 shares remaining and available for grant under the 2019 Plan that terminated pursuant to the approval of the 2020 Plan. The 2020 Plan permits the Company to issue up to 5,750,000 shares reserved for issuance pursuant to the 2020 Plan and any additional shares which may be issued if awards outstanding under the Registrant’s 2014, 2016, 2018 and 2019 Plans are canceled or expire.

The Company’s stock options have a maximum term of 10 years from the date of grant. Stock options granted may be either incentive stock options or nonqualified stock options and the exercise price of stock options must be at least equal to the fair market value of the common stock on the date of grant. The Company’s general policy is to issue common shares upon the exercise of stock options.

The Company estimates the fair value of each stock award on the grant date using the Black-Scholes option-pricing model based on the following assumptions:


	Years Ended December 31,
	2021	2020
Risk free interest rate	0.46% - 1.20%	0.33% - 1.53%
Expected term (in years)	5.31 - 5.73	5 - 5.73
Dividend yield	—	—
Expected volatility	75.0% - 81.7%	70.0% - 75.8%

The weighted-average fair value of the 3,182,696 and 2,311,481 options granted during the years ended December 31, 2021 and 2020 was $2.04 and $1.92, respectively. As of December 31, 2021, there were 3,282,399 shares available for future grant under the 2020 Plan.

The following table summarizes stock option activity for employees and non-employees:


	Number of Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2020	9,591,123	$	3.44		$	2,303
Granted	2,822,696	3.05			—
Exercised	482,115	2.14			1,106
Canceled	379,991	4.96			102
Outstanding, December 31, 2021	11,551,713	$	3.34	6.71 years	$	11,402
Vested or expected to vest, December 31, 2021	11,551,713	$	3.34	6.71 years	$	11,402
Exercisable, December 31, 2021	7,376,177	$	3.45	5.52 years	$	7,964

Periodically, the Company grants inducement options, which are awards outside of approved stock option plans, and which are material awards to the executive officers or other personnel entering senior leadership roles with the Company. The terms of inducement option awards were substantially the same as those issued under our 2020 Plan. These awards are excluded from the table above. The following table summarizes stock option activity for these inducement options (in thousands):


	Number of Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2020	420,313	$	5.00		$	—
Granted	360,000	$	3.48		$	—
Canceled or Expired	120,313	$	5.87		$	—
Outstanding, December 31, 2021	660,000	$	4.01	8.71 years	$	108
Vested or expected to vest, December 31, 2021	660,000	$	4.01	8.71 years	$	108
Exercisable, December 31, 2021	168,750	$	4.65	7.66 years	$	—

Employee Stock Purchase Plans

The 2018 ESPP provides eligible employees with the opportunity, through regular payroll deductions, to purchase shares of the Company’s common stock at 85% of the lower closing market price of the common stock at the beginning date or ending date of each purchase period. The plan includes two six-month purchase periods per year beginning in both June and December. The Company has reserved 500,000 shares of common stock for the administration of the 2018 ESPP. Total shares purchased under the plan were 64,257 and 69,544 for the years ended December 31, 2021 and 2020, respectively. The fair value of shares expected to be purchased under the 2018 ESPP was determined using the Black-Scholes model with the following assumptions:


	Years Ended December 31,
	2021	2020
Risk free interest rate	0.04% - 0.10%	0.10% - 0.18%
Expected term (in years)	0.5 years	0.5 years
Dividend yield	—	—
Expected volatility	60.46% - 131.21%	74.36% - 120.89%

Total Stock-based Compensation Expense

Total stock-based compensation expense is recorded in operating expenses based upon the functional responsibilities of the individuals holding the respective options as follows (in thousands):


	Years Ended December 31,
	2021		2020
Research and development	$	2,274	$	2,394
General and administrative	2,941		2,696
Total stock-based compensation	$	5,215	$	5,090

As of December 31, 2021, the total unrecognized compensation cost related to all non-vested awards was $8.1 million of which $1.2 million are for inducement options. The Company expects to recognize the compensation cost over a remaining weighted-average period of 2.64 years.

License Agreement	12 Months Ended
License Agreement	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
License Agreement	License Agreement TUM License The Company and the Technical University of Munich, or TUM, initiated discussions in the second quarter of 2018 to clarify, expand and restructure the research and licensing agreement with TUM, the TUM License, including the parties’ obligations under the TUM License. The TUM License assigns or exclusively licenses to the Company certain intellectual property related to the Company's Anticalin platform technology. The parties' discussions relate to revised commercial terms and to re-initiating additional collaborations between faculty at TUM and Pieris. While an amended and restated license agreement has not yet been completed, the Company intends to enter into such an amendment. These discussions may also lead to an increase in the Company's collaborative research activities with TUM.

Leases

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Leases

The Company currently leases office space in Boston, Massachusetts. In August 2015, the Company entered into a sublease to lease approximately 3,950 square feet. The sublease originally expired on February 27, 2022 or such earlier date pursuant to the termination provisions of the sublease. In July 2021, the Company extended the lease for this office space for an additional 10 months through December 31, 2022.

In October 2018, Pieris GmbH entered into a lease for office and laboratory space located in Hallbergmoos, Germany, or the Hallbergmoos Lease. Pieris GmbH moved its operations, formerly conducted in Freising, Germany, to the Hallbergmoos facility in February 2020.

Under the Hallbergmoos Lease, Pieris GmbH rents approximately 105,000 square feet, of which approximately 96,400 square feet were delivered by the lessor in February 2020 and approximately 8,600 square feet were delivered by the lessor by May 2020. An additional approximately 22,300 square feet is expected to be delivered by the lessor by October 2024. Pieris GmbH has a first right of refusal to lease an additional approximate 13,400 square feet.

The Hallbergmoos Lease provides for an initial rental term of 12.5 years which commenced in February 2020 when the leased property was delivered to Pieris GmbH. Pieris GmbH also has an option to extend the Hallbergmoos Lease for two additional 60-month periods. The Company is not reasonably certain to exercise the option to extend the lease expiration beyond its current expiration date. Pieris GmbH may sublease space within the leased property with lessor’s consent, which may not be unreasonably withheld.

Monthly base rent for the initial 105,000 square feet of the leased property, including parking spaces, will total approximately $0.2 million per month, which amount shall be adjusted starting on the second anniversary of the commencement date by an amount equal to the German consumer price index. In addition to the base rent, Pieris GmbH is also responsible for certain administrative and operational costs in accordance with the Hallbergmoos Lease. Pieris GmbH provided a security deposit of $0.8 million at upon signing the lease agreement. The Company will serve as a guarantor for the Hallbergmoos Lease.

The Hallbergmoos Lease included $11.5 million of tenant improvements allowance for normal tenant improvements, for which construction began in March 2019. The Company capitalized the leasehold incentives which are included in Property and equipment, net on the Consolidated Balance Sheet and are amortized on a straight-line basis over the shorter of the useful life or the remaining lease term.

The Company also leased approximately 19,000 square feet of office and laboratory space in Freising, Germany under four agreements, the Freising Leases, including three leases for space on three floors of the same building and a letter agreement for additional conference room space within the building. The Freising Leases all terminated on March 31, 2020.

The following table summarizes operating lease costs included in operating expenses (in thousands):


	Years Ended December 31,
	2021		2020
Operating lease costs	$	1,483	$	1,509
Variable lease costs (1)	739		708
Total lease cost	$	2,222	$	2,217
(1) Variable lease costs include certain additional charges for operating costs, including insurance, maintenance, taxes, utilities, and other costs incurred, which are billed based on both usage and as a percentage of the Company’s share of total square footage.

The following table summarizes the weighted-average remaining lease term and discount rate:


	As of December 31,
	2021		2020
Weighted-average remaining lease term (years)	10.4		11.4
Weighted-average discount rate	10.5	%	10.5	%

Cash paid for amounts included in the measurement of the lease liabilities were $2.6 million and $2.2 million for the twelve months ended December 31, 2021 and 2020, respectively.

As of December 31, 2021, the maturities of the Company’s operating lease liabilities and future minimum lease payments were as follows (in thousands):


	Total
2022	$	2,474
2023	2,235
2024	2,235
2025	2,235
2026	2,235
Thereafter	12,482
Total undiscounted lease payments	23,896
Less: present value adjustment	(9,006)
Present value of lease liabilities	14,890

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation and Use of Estimates The accompanying consolidated financial statements of Pieris Pharmaceuticals, Inc. and its wholly-owned subsidiaries were prepared in accordance with U.S. GAAP. The consolidated financial statements include the accounts of all subsidiaries. All intercompany balances and transactions have been eliminated.
Use of Estimates	The preparation of the financial statements in accordance with U.S. GAAP requires management to make estimates, judgments, and assumptions that affect the reported amounts of assets, liabilities, revenues, expenses and the related disclosures at the date of the financial statements and during the reporting period. Significant estimates are used for, but are not limited to, revenue recognition; deferred tax assets, deferred tax liabilities and valuation allowances; determination of the incremental borrowing rate to calculate right-of-use assets and lease liabilities; beneficial conversion features; fair value of stock options, preferred stock, and warrants; and prepaid and accrued clinical trial expenses. Management evaluates its estimates on an ongoing basis. Actual results and outcomes could differ materially from management’s estimates, judgments, and assumptions.
Foreign Currency Translation	Foreign Currency Translation The financial statements of the Company’s foreign subsidiaries are translated from local currency into reporting currency, which is U.S. dollars, using the current exchange rate at the balance sheet date for assets and liabilities, and the weighted average exchange rate prevailing during the period for revenues and expenses. The functional currency for Pieris’ foreign subsidiaries is considered to be the local currency for each entity and, accordingly, translation adjustments for these subsidiaries are included in accumulated other comprehensive loss within stockholders’ equity. Realized and unrealized gains and losses resulting from foreign currency transactions denominated in currencies other than the functional currency are reflected as other (expense) income, net in the consolidated statements of operations. Foreign currency gains and losses on available-for-sale investment transactions are recorded to other comprehensive income (loss) on the Company's balance sheet per Financial Accounting Standards Board, or FASB, Accounting Standards Codification, or ASC, Topic 830, Foreign Currency Matters.
Cash, Cash Equivalents and Investments	Cash, Cash Equivalents and Investments The Company determines the appropriate classification of its investments at the time of purchase. All liquid investments with original maturities of 90 days or less from the purchase date and for which there is an active market are considered to be cash equivalents. The Company’s investments are comprised of money market, asset backed securities, government treasuries, and corporate bonds that are classified as available-for-sale in accordance with FASB ASC 320, Investments—Debt and Equity Securities. The Company classifies investments available to fund current operations as current assets on its balance sheets. Available-for-sale investments are recorded at fair value, with unrealized gains or losses included in accumulated other comprehensive income (loss) on the Company’s balance sheets. Realized gains and losses are determined using the specific identification method and are included as a component of other income (expense). The Company reviews investments for other-than-temporary impairment whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. To determine whether an impairment is other-than temporary, the Company considers its intent to sell, or whether it is more likely than not that the Company will be required to sell the investment before recovery of the investment’s amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, the severity and the duration of the impairment, and changes in value subsequent to period end.
Concentration of Credit Risk and Off-Balance Sheet Risk	Concentration of Credit Risk and Off-Balance Sheet Risk The Company has no financial instruments with off‑balance sheet risk such as foreign exchange contracts, option contracts, or other foreign hedging arrangements. Financial instruments that subject Pieris to concentrations of credit risk include cash and cash equivalents, investments, and accounts receivable. The Company’s cash, cash equivalents, and investments are held in accounts with financial institutions that management believes are creditworthy. The Company’s investment policy includes guidelines on the quality of the institutions and financial instruments and defines allowable investments that the Company believes minimizes the exposure to concentration of credit risk. The Company has not experienced any credit losses in such accounts and does not believe it is exposed to any significant credit risk on these funds. Accounts receivable primarily consist of amounts due under strategic partnership and other license agreements with major multi-national pharmaceutical companies for which the Company does not obtain collateral.
Fair Value Measurement	Fair Value Measurement The Company is required to disclose information on all assets and liabilities reported at fair value that enables an assessment of the inputs used in determining the reported fair values. FASB ASC Topic 820, Fair Value Measurement and Disclosures, or ASC 820, established a hierarchy of inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the observable inputs be used when available. Observable inputs are inputs that market participants would use in pricing the financial instrument based on market data obtained from sources independent of the Company. Unobservable inputs are inputs that reflect the Company’s assumptions about the inputs that market participants would use in pricing the financial instrument and are developed based on the best information available in the circumstances. The fair value hierarchy applies only to the valuation inputs used in determining the reported or disclosed fair value of the financial instruments and is not a measure of the investment credit quality. Fair value measurements are classified and disclosed in one of the following three categories: •Level 1 inputs are quoted prices in active markets for identical assets or liabilities that the reporting entity has the ability to access at the measurement date. •Level 2 utilizes quoted market prices in markets that are not active, broker or dealer quotations, or alternative pricing sources with reasonable levels of price transparency. •Level 3 inputs are unobservable inputs for the asset or liability in which there is little, if any, market activity for the asset or liability at the measurement date. To the extent that valuation is based on models or inputs that are less observable or unobservable in the market, the determination of fair value requires more judgment. Accordingly, the degree of judgment exercised by the Company in determining fair value is greatest for instruments categorized in Level 3. A financial instrument’s level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Financial instruments measured at fair value on a recurring basis include cash equivalents and investments, if any (Note 6). An entity may elect to measure many financial instruments and certain other items at fair value at specified election dates. Subsequent unrealized gains and losses on items for which the fair value option has been elected will be reported in net loss. The Company did not elect to measure any additional financial instruments or other items at fair value.
Fair Values of Financial Instruments	Fair Values of Financial Instruments The fair value of cash, accounts receivable, and accounts payable approximates the carrying value of these financial instruments because of the short-term nature of any maturities. The Company determines the estimated fair values of other financial instruments, using available market information and valuation methodologies, primarily input from independent third party pricing sources.
Accounts Receivable	Accounts Receivable Accounts receivable are recorded net of allowances for doubtful accounts and represent amounts due from strategic partners. The Company monitors and evaluates collectability of receivables on an ongoing basis and considers whether an allowance for doubtful accounts is necessary. The Company determined that no such reserve is needed as of December 31, 2021 and 2020. Historically, Pieris has not had collectability issues.
Property and Equipment	Property and EquipmentProperty and equipment are recorded at acquisition cost, less accumulated depreciation and impairment. Depreciation on property and equipment is calculated using the straight-line method over the remaining estimated useful lives of the assets. Maintenance and repairs to these assets are charged to expenses as occurred. During the year ended December 31, 2020, the Company added material assets related to the February 2020 move to a new research and development facility in Hallbergmoos, Germany.
Impairment of Long-lived Assets	Impairment of Long-lived Assets The Company reviews its long-lived assets to be held and used for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. The Company evaluates the realizability of its long-lived assets based on profitability and cash flow expectations for the related asset. Any write-downs are treated as permanent reductions in the carrying amount of the assets. The Company believes that, as of each of the balance sheets presented, none of the Company’s long-lived assets were impaired.
Revenue Recognition	Revenue Recognition Pieris has entered into several licensing agreements with collaboration partners for the development of Anticalin therapeutics against a variety of targets. The terms of these agreements provide for the transfer of multiple goods or services which may include: (i) licenses, or options to obtain licenses, to Pieris’ Anticalin technology and/or specific programs and (ii) research and development activities to be performed on behalf of or with a collaborative partner. Payments to Pieris under these agreements may include upfront fees (which include license and option fees), payments for research and development activities, payments based upon the achievement of certain milestones, and royalties on product sales. There are no performance, cancellation, termination or refund provisions in any of the arrangements that could result in material financial consequences to Pieris. As the Company's intellectual property is located in Germany, the Company records all consolidated revenue in its Pieris Pharmaceuticals, GmbH subsidiary. Collaborative Arrangements The Company considers the nature and contractual terms of an arrangement and assess whether the arrangement involves a joint operating activity pursuant to which it is an active participant and exposed to significant risks and rewards with respect to the arrangement. If the Company is an active participant and exposed to the significant risks and rewards with respect to the arrangement, it accounts for these arrangements pursuant to ASC 808, Collaborative Arrangements, or ASC 808, and applies a systematic and rational approach to recognize revenue. The Company classifies payments received as revenue and payments made as a reduction of revenue in the period in which they are earned. Revenue recognized under a collaborative arrangement involving a participant that is not a customer is presented as Collaboration Revenue in the Statement of Operations. In November 2018, the FASB issued ASU 2018-18, which makes targeted improvements to U.S. GAAP for collaborative arrangements, including: clarification that certain transactions between collaborative arrangement participants should be accounted for as revenue under ASC 606, Revenue from Contracts with Customers, or ASC 606, when the collaborative arrangement participant is a customer in the context of a unit of account; adding unit-of-account guidance in ASC 808 to align with the guidance in ASC 606; and a requirement that in a transaction with a collaborative arrangement participant that is not directly related to sales to third parties, presenting the transaction together with revenue recognized under ASC 606 is precluded if the collaborative arrangement participant is not a customer. The guidance per ASU 2018-18 was adopted retrospectively to the date of initial application of ASC 606. The Company adopted ASU 2018-18 in the first quarter of 2020. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements; however, revenue recognized under a collaborative arrangement involving a participant that is not a customer (Collaboration revenue) is now presented separately from Customer revenue. All amounts presented herein are in conformity with ASU 2018-18. Revenue from Contracts with Customers In accordance with ASC 606, revenue is recognized when a customer obtains control of promised goods or services. The amount of revenue recognized reflects the consideration to which the Company expects to be entitled in exchange for these goods and services. To achieve this core principle, the Company applies the following five steps: 1) identify the customer contract; 2) identify the contract’s performance obligations; 3) determine the transaction price; 4) allocate the transaction price to the performance obligations; and 5) recognize revenue when or as a performance obligation is satisfied. The Company evaluates all promised goods and services within a customer contract and determines which of such goods and services are separate performance obligations. This evaluation includes an assessment of whether the good or service is capable of being distinct and whether the good or service is separable from other promises in the contract. In assessing whether promised goods or services are distinct, the Company considers factors such as the stage of development of the underlying intellectual property and the capabilities of the customer to develop the intellectual property on their own or whether the required expertise is readily available. Licensing arrangements are analyzed to determine whether the promised goods or services, which often include licenses, research and development services and governance committee services, are distinct or whether they must be accounted for as part of a combined performance obligation. If the license is considered not to be distinct, the license would then be combined with other promised goods or services as a combined performance obligation. If the Company is involved in a governance committee, it assesses whether its involvement constitutes a separate performance obligation. When governance committee services are determined to be separate performance obligations, the Company determines the fair value to be allocated to this promised service. Certain contracts contain optional and additional items, which are considered marketing offers and are accounted for as separate contracts with the customer if such option is elected by the customer, unless the option provides a material right which would not be provided without entering into the contract. An option that is considered a material right is accounted for as a separate performance obligation. The transaction price is determined based on the consideration to which the Company will be entitled in exchange for transferring goods and services to the customer. A contract may contain variable consideration, including potential payments for both milestone and research and development services. For certain potential milestone payments, the Company estimates the amount of variable consideration by using the most likely amount method. In making this assessment, the Company evaluates factors such as the clinical, regulatory, commercial and other risks that must be overcome to achieve the milestone. Each reporting period the Company re-evaluates the probability of achievement of such variable consideration and any related constraints. Pieris will include variable consideration, without constraint, in the transaction price to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. For potential research and development service payments, the Company estimates the amount of variable consideration by using the expected value method, including any approved budget updates arising from additional research or development services. If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price among the performance obligations on a relative standalone selling price basis unless a portion of the transaction price is variable and meets the criteria to be allocated entirely to a performance obligation or to a distinct good or service that forms part of a single performance obligation. The Company allocates the transaction price based on the estimated standalone selling price of the underlying performance obligations or in the case of certain variable consideration to one or more performance obligations. The Company must develop assumptions that require judgment to determine the stand-alone selling price for each performance obligation identified in the contract. The Company utilizes key assumptions to determine the stand-alone selling price, which may include other comparable transactions, pricing considered in negotiating the transaction and the estimated costs to complete the respective performance obligation. Certain variable consideration is allocated specifically to one or more performance obligations in a contract when the terms of the variable consideration relate to the satisfaction of the performance obligation and the resulting amounts allocated to each performance obligation are consistent with the amount the Company would expect to receive for each performance obligation. When a performance obligation is satisfied, revenue is recognized for the amount of the transaction price, excluding estimates of variable consideration that are constrained, that is allocated to that performance obligation on a relative standalone selling price basis. Significant management judgment is required in determining the level of effort required under an arrangement and the period over which the Company is expected to complete its performance obligations under an arrangement. For performance obligations consisting of licenses and other promises, the Company utilizes judgment to assess the nature of the combined performance obligation to determine whether the combined performance obligation is satisfied over time or at a point in time and, if over time, the appropriate method of measuring progress for purposes of recognizing revenue from non- refundable, up-front fees. The Company evaluates the measure of progress each reporting period and, if necessary, adjusts the measure of performance and related revenue recognition. If the license to the Company’s intellectual property is determined to be distinct from the other performance obligations identified in the arrangement, the Company will recognize revenue from non-refundable, up-front fees allocated to the license when the license is transferred to the customer and the customer is able to use and benefit from the license. Revenue recognized under an arrangement involving a participant that is a customer is presented as Customer Revenue. Milestones and Royalties The Company aggregates milestones into four categories (i) research milestones, (ii) development milestones, (iii) commercial milestones and (iv) sales milestones. Research milestones are typically achieved upon reaching certain success criteria as defined in each agreement related to developing an Anticalin protein against the specified target. Development milestones are typically reached when a compound reaches a defined phase of clinical research or passes such phase, or upon gaining regulatory approvals. Commercial milestones are typically achieved when an approved pharmaceutical product reaches the status for commercial sale, including regulatory approval. Sales milestones are certain defined levels of net sales by the licensee, such as when a product first achieves global sales or annual sales of a specified amount. There is uncertainty that the events to obtain the research and development milestones will be achieved given the nature of clinical development and the stage of the Company’s technology. The Company has thus determined that all research and development milestones will be constrained until it is deemed probable that a significant revenue reversal will not occur. For revenues from research and development milestones, payments will be recognized consistent with the recognition pattern of the performance obligation to which they relate. For arrangements that include sales-based royalties, including milestone payments based on the level of sales, and for which the license is deemed to be the predominant item to which the royalties relate, the Company recognizes revenue at the later of (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the royalty has been allocated has been satisfied (or partially satisfied). Commercial milestones and sales royalties are determined by sales or usage-based thresholds and will be accounted for under the royalty recognition constraint as constrained variable consideration. The Company calculates the maximum amount of potential milestones achievable under each collaboration agreement and discloses such potential future milestones for all current collaborations using such a maximum calculation. Contract Balances The Company recognizes a contract asset when the Company transfers goods or services to a customer before the customer pays consideration or before payment is due, excluding any amounts presented as a receivable (i.e., accounts receivable). A contract asset is an entity’s right to consideration in exchange for goods or services that the entity has transferred to a customer. The contract liabilities (i.e., deferred revenue) primarily relate to contracts where the Company has received payment but has not yet satisfied the related performance obligations. In the event of an early termination of a collaboration agreement, any contract liabilities would be recognized in the period in which all Company obligations under the agreement have been fulfilled. Costs to Obtain and Fulfill a Contract with a Customer Certain costs to obtain customer contracts, including success-based fees paid to third-party service providers, and costs to fulfill customer contracts are capitalized in accordance with FASB ASC 340, Other Assets and Deferred Costs, or ASC 340. These costs are amortized to expense on a systemic basis that is consistent with the transfer to the customer of the goods or services to which the asset relates. The Company will expense the amortization of costs to obtain customer contracts to general and administrative expense and costs to fulfill customer contracts to research and development expense.
Research and Development	Research and Development Research and development expenses are charged to the statement of operations as incurred. Research and development expenses are comprised of costs incurred in performing research and development activities, including salaries and benefits, facilities costs, pre-clinical and clinical costs, contract services, consulting, depreciation and amortization expense, and other related costs. Costs associated with acquired technology, in the form of upfront fees or milestone payments, are charged to research and development expense as incurred.
Income Taxes	Income Taxes The Company applies ASC Topic 740 Income Taxes, which established financial accounting and reporting requirements for the effects of income taxes that result from the Company’s activities during the current and preceding years. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, and operating losses and tax credit carry forwards. Deferred tax assets and liabilities are measured using enacted statutory tax rates expected to apply to taxable income in the jurisdictions and years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. Where the Company determines that it is more likely than not that some portion or all of the deferred tax assets will not be realized in the future, the deferred tax assets are reduced by a valuation allowance. The Company records interest and penalties related to uncertain tax positions as part of income tax expense. The Tax Cuts and Jobs Act (TCJA) subjects a U.S. shareholder to tax on global-intangible low tax income (GILTI) earned by certain foreign subsidiaries. The Company has made an accounting policy election to provide for the tax expense related to GILTI in the year the tax is incurred as a period expense only.
Stock-based Compensation	Stock-based Compensation The Company measures share-based payments in accordance with ASC Topic 718, Stock Compensation. Pieris records its stock-based compensation expense over the requisite service period and records forfeitures as they occur. Determining the appropriate fair value model and related assumptions requires judgment, including estimating share price volatility and expected terms of the awards. For employee options, the fair value measurement date is generally on the date of grant and the related compensation expense is recognized on a straight-line basis over the requisite service period of the awards, less expense for actual forfeitures. The Company uses the Black-Scholes option pricing model to determine the estimated fair value for stock-based awards. Option-pricing models require the input of various subjective assumptions, including the option’s expected life, expected dividend yield, price volatility, risk free interest rate and forfeitures of the underlying stock. Due to the limited operating history of the Company as a public entity and a lack of company specific historical and implied volatility data, the Company has based its estimate of expected volatility on the historical volatility of a group of similar companies that are publicly traded. When selecting these public companies on which it has based its expected stock price volatility, the Company selected companies with comparable characteristics to it, including enterprise value, risk profiles, position within the industry, and with historical share price information sufficient to meet the expected term of the stock-based awards. The Company computes historical volatility data using the daily closing prices for the selected companies’ shares during the equivalent period of the calculated expected term of the stock-based awards. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available. Due to the lack of Company specific historical option activity, the Company has estimated the expected term of its employee stock options using the “simplified” method, whereby, the expected term equals the arithmetic average of the vesting term and the original contractual term of the option. The expected term for non-employee awards is the remaining contractual term of the option. The risk-free interest rates are based on the U.S. Treasury securities with a maturity date commensurate with the expected term of the associated award. The Company has never paid, and does not expect to pay dividends in the foreseeable future. All excess tax benefits and tax deficiencies are recorded as income tax expense or benefit in the Company's statement of operations and comprehensive loss.
Government Grants	Government GrantsThe Company recognizes grants from governmental agencies when there is reasonable assurance that the Company will comply with the conditions attached to the grant arrangement and the grant will be received. The Company evaluates the conditions of each grant as of each reporting period to evaluate whether the Company has reached reasonable assurance of meeting the conditions of each grant arrangement and that it is expected that the grant will be received as a result of meeting the necessary conditions. Grants are recognized in the consolidated statements of operations on a systematic basis over the periods in which the Company recognizes the related costs for which the government grant is intended to compensate. Specifically, grant income related to research and development costs is recognized as such expenses are incurred. Grant income is included as a separate caption within Other income (expense), net in the consolidated statements of operations.
Leases	Leases The Company accounts for leases pursuant to ASC 842 Leases (Topic 842), or ASC 842. As a lessee, the Company is required to recognize (i) a lease liability, which is a lessees obligation to make lease payments arising from a lease, measured on a discounted basis; and (ii) a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term for all leases (with the exception of short-term leases) at the commencement date. Any variable components of lease costs are excluded from lease payments and are recognized in the period incurred. The Company determines if an arrangement is a lease at inception. The Company’s contracts are determined to contain a lease within the scope of ASC 842 when all of the following criteria based on the specific circumstances of the arrangement are met: (1) there is an identified asset for which there are no substantive substitution rights; (2) the Company has the right to obtain substantially all of the economic benefits from the identified asset; and (3) the Company has the right to direct the use of the identified asset. In addition, the Company does not apply the recognition requirements in the lease standard to short-term leases (a lease that at commencement date has a lease term of 12 months or less and does not contain a purchase option that it is reasonably certain to exercise) and does not separate lease and non-lease components for all asset classes. Any variable components of lease costs are excluded from lease payments and are recognized in the period incurred. At the commencement date, operating lease liabilities and their corresponding right-of-use assets are recorded based on the present value of future lease payments over the expected lease term. The Company’s lease agreements do not provide an implicit rate. As a result, the Company utilizes an estimated incremental borrowing rate to discount lease payments, which is based on the rate of interest the Company would have to pay to borrow a similar amount on a collateralized basis over a similar term and based on observable market data points. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or lease incentives received. Operating lease cost is recognized over the expected term on a straight-line basis. The Company typically only includes an initial lease term in its assessment of a lease agreement. Options to renew a lease are not included in the Company’s assessment unless there is reasonable certainty that the Company will renew. The expected lease term includes noncancelable lease periods and, when applicable, periods covered by an option to extend the lease if the Company is reasonably certain to exercise that option, as well as periods covered by an option to terminate the lease if the Company is reasonably certain not to exercise that option. Assumptions made by the Company at the commencement date are re-evaluated upon occurrence of certain events, including a lease modification. A lease modification results in a separate contract when the modification grants the lessee an additional right of use not included in the original lease and when lease payments increase commensurate with the standalone price for the additional right of use. When a lease modification results in a separate contract, it is accounted for in the same manner as a new lease.
Contingencies	Contingencies Accruals are recorded for loss contingencies when it is probable that a liability has been incurred and the amount of the related loss can be reasonably estimated. The Company evaluates, on a quarterly basis, developments in legal proceedings and other matters that could cause an increase or decrease in the amount of the liability that has been accrued previously. Considering facts known at the time of the assessment, the Company determines whether potential losses are considered reasonably possible or probable and whether they are estimable. Based upon this assessment, the Company carries out an evaluation of disclosure requirements and considers possible accruals in the financial statements.
Segment Reporting	Segment Reporting Operating segments are identified as components of an enterprise where separate discrete financial information is evaluated by the chief operating decision maker in making decisions on how to allocate resources and assess performance. The Company operates as a single segment dedicated to the discovery and development of biotechnological applications and the Company’s chief operating decision maker, or CODM, makes decisions based on the Company as a whole. The Company has determined that its CODM is its Chief Executive Officer.
Earnings per Share	Earnings per Share Basic earnings per share attributable to common stockholders is calculated by dividing net loss attributable to common stockholders by the weighted average shares outstanding during the period, without consideration for common stock equivalents. Diluted earnings per share attributable to common stockholders is calculated by adjusting weighted average shares outstanding for the dilutive effect of common stock equivalents outstanding for the period, determined using the treasury-stock and if-converted methods. For purposes of the diluted net loss per share attributable to common stockholders' calculation, preferred stock, stock options, unvested restricted stock, and warrants are considered to be common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders, as their effect would be anti-dilutive for all periods presented. Therefore, basic and diluted net loss per share were the same for all periods presented.
Recent Accounting Pronouncements Adopted and Not Yet Adopted	Recent Accounting Pronouncement Adopted In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes which amends and aims to simplify accounting disclosure requirements regarding a number of topics including intraperiod tax allocation, accounting for deferred taxes when there are changes in consolidation of certain investments, tax basis step up in an acquisition and the application of effective rate changes during interim periods, among other improvements. This standard is effective for fiscal years beginning after December 15, 2020 and was adopted by the Company on January 1, 2021. Adoption of this new standard did not have a material impact on the Company. In November 2021, the FASB issued ASU No. 2021-10, Government Assistance (Topic 832), or ASU 2021-10. ASU 2021-10 provides clarity on increasing transparency over the disclosure of certain government assistance including the disclosure of (1) the types of assistance, (2) an entity’s accounting for the assistance, and (3) the effect of the assistance on an entity’s financial statements. Diversity currently exists in the recognition, measurement, presentation, and disclosure of government assistance received by business entities because of the lack of specific authoritative guidance in generally accepted accounting principles. The guidance in ASU 2021-10 is effective for the Company for financial statements issued for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company adopted this standard for the period ended December 31, 2021 on a prospective basis and concluded that we have made the required disclosure in Footnote 5 below. Recent Accounting Pronouncements Not Yet Adopted In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Statements, or ASU 2016-13. ASU 2016-13 significantly changes the impairment model for most financial assets and certain other instruments. The new standard requires that expected credit losses relating to financial assets measured on an amortized cost basis and available-for-sale debt securities be recorded through an allowance for credit losses. It also limits the amount of credit losses to be recognized for available-for-sale debt securities to the amount by which carrying value exceeds fair value, and requires the reversal of previously recognized credit losses if fair value increases. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of the financial asset(s) to present the net carrying value at the amount expected to be collected on the financial asset. Subsequently, in November 2018, the FASB issued ASU No. 2018-19, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, which clarifies codification and corrects unintended application of the guidance. In November 2019, the FASB issued ASU No. 2019-11, Codification Improvements to Topic 326, Financial Instruments-Credit Losses, which clarifies or addresses specific issues about certain aspects of ASU 2016-13. In November 2019 the FASB also issued ASU No. 2019-10, Financial Instruments-Credit Losses (Topic 326), Derivatives and Hedging (Topic 815), and Leases (Topic 842): Effective Dates, which delays the effective date of ASU 2016-13 by three years for certain smaller reporting companies such as the Company. The guidance in ASU 2016-13 is effective for the Company for financial statements issued for fiscal years beginning after December 15, 2022 and interim periods within those fiscal years, with early adoption permitted. The Company is still evaluating the impact of the adoption of this standard. The Company has considered other recent accounting pronouncements and concluded that they are either not applicable to the business, or that the effect is not expected to be material to the unaudited consolidated financial statements as a result of future adoption.

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Schedule of Property and Equipment, Useful Lives

The estimated useful life of the different groups of property and equipment is as follows:


Asset Classification						Estimated useful life (in years)
Leasehold improvements						shorter of useful life or remaining life of the lease
Laboratory furniture and equipment						8 - 14
Office furniture and equipment						5 - 13
Computer and equipment						3 - 7

Property and equipment are summarized as follows (in thousands):


	Years Ended December 31,
	2021		2020
Leasehold improvements	$	13,130	$	14,159
Laboratory equipment	11,354		11,188
Office furniture and equipment	1,959		2,120
Computer equipment	396		394
Property and equipment at cost	26,839		27,861
Accumulated depreciation	(7,717)		(5,815)
Property and equipment, net	$	19,122	$	22,046

Revenue (Tables)

12 Months Ended

Dec. 31, 2021

Revenue from Contract with Customer [Abstract]

Schedule of Recognized Revenues

During the years ended December 31, 2021 and 2020, respectively, the Company recognized revenue from the following strategic partnerships and other license agreements (in thousands):


	Years Ended December 31,
	2021		2020
AstraZeneca	$	18,919	$	8,308
Seagen	768		9,702
Servier	4,070		11,313
Boston Pharmaceuticals	5,711		—
Genentech	1,950		—
Total Revenue	$	31,418	$	29,323

Schedule of Potential Milestone Payments

Under the Company´s existing strategic partnerships and other license agreements, the Company could receive the following potential milestone payments (in millions) as of December 31, 2021:


	Research, Development, Regulatory & Commercial Milestones		Sales Milestones
AstraZeneca	$	1,096	$	4,275
Servier	136		102
Seagen	754		450
Boston Pharmaceuticals	88		265
Genentech	844		600
Total potential milestone payments	$	2,918	$	5,692

Property and Equipment, Net (Tables)

12 Months Ended

Dec. 31, 2021

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment

The estimated useful life of the different groups of property and equipment is as follows:


Asset Classification						Estimated useful life (in years)
Leasehold improvements						shorter of useful life or remaining life of the lease
Laboratory furniture and equipment						8 - 14
Office furniture and equipment						5 - 13
Computer and equipment						3 - 7

Property and equipment are summarized as follows (in thousands):


	Years Ended December 31,
	2021		2020
Leasehold improvements	$	13,130	$	14,159
Laboratory equipment	11,354		11,188
Office furniture and equipment	1,959		2,120
Computer equipment	396		394
Property and equipment at cost	26,839		27,861
Accumulated depreciation	(7,717)		(5,815)
Property and equipment, net	$	19,122	$	22,046

Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2021

Payables and Accruals [Abstract]

Schedule of Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):


	Years Ended December 31,
	2021		2020
Research and development fees	$	5,682	$	2,001
Compensation expense	3,581		2,759
Accrued accounts payable	2,980		1,220
Collaboration cost-sharing obligation	1,610		16
Accrued license obligations	1,541		358
Lease liabilities	1,049		1,030

Other current liabilities	393		347
Total	$	16,836	$	7,731

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of Loss before Income Taxes

The Company reported a loss before income taxes consisting of the following (in thousands):


	Years Ended December 31,
	2021		2020
Domestic	$	(11,312)	$	(12,134)
Foreign	(34,426)		(24,932)
Loss before income taxes	$	(45,738)	$	(37,066)

Schedule of Components of (Benefit) Provision for Income Taxes

The components of the provision for income taxes are as follows (in thousands):


	Years Ended December 31,
	2021		2020
Current:
Federal	$	—	$	—
State	—		—
Foreign	—		164
Total current	—		164
Deferred:
Federal	—		—
State	—		—
Foreign	—		—
Total deferred	—		—
Provision for income taxes	$	—	$	164

Schedule of Reconciliation of Effective Tax Rate

The reconciliation of the federal statutory rate to the Company’s effective tax rate is as follows:


	2021		2020
Federal income tax rate	21.0	%	21.0	%

Foreign rate differential	5.6		1.9
State tax, net of federal benefit	1.2		1.9
US tax on foreign income	—		—
Share-based awards compensation	(3.5)		(3.8)
Permanent items	(0.2)		(2.4)
Provision to return	3.3		—
Other	—		(0.4)

Change in valuation allowance	(27.4)		(18.7)
Effective income tax rate	—	%	(0.5)	%

Schedule of Components of Deferred Tax Assets and Liabilities


	Years Ended December 31,
	2021		2020
Deferred tax assets:
Net operating loss carryforwards	$	49,280	$	39,175
Share-based awards compensation	2,739		2,913
Accrued expenses	323		230
Depreciation and other	384		297

Unrealized foreign currency	256		771
Lease liability	4,022		4,582
Total deferred tax assets	57,004		47,968
Deferred tax liabilities:
Right-of-use asset	(3,729)		(4,235)

Accrued expenses	(68)		—
Total deferred tax liabilities	(3,797)		(4,235)
Less: valuation allowance:	(53,207)		(43,733)
Net deferred tax asset	$	—	$	—

Schedule of Reconciliation of Unrecognized Tax Benefits Excluding Impact of Interest and Penalties


Unrecognized tax benefits at December 31, 2020	$	6,135
Currency translation adjustment	(470)
Unrecognized tax benefits at December 31, 2021	$	5,665

Stock and Employee Benefit Plans (Tables)

12 Months Ended

Dec. 31, 2021

Share-based Payment Arrangement [Abstract]

Schedule of Fair Value Assumptions

The Company estimates the fair value of each stock award on the grant date using the Black-Scholes option-pricing model based on the following assumptions:


	Years Ended December 31,
	2021	2020
Risk free interest rate	0.46% - 1.20%	0.33% - 1.53%
Expected term (in years)	5.31 - 5.73	5 - 5.73
Dividend yield	—	—
Expected volatility	75.0% - 81.7%	70.0% - 75.8%

The fair value of shares expected to be purchased under the 2018 ESPP was determined using the Black-Scholes model with the following assumptions:


	Years Ended December 31,
	2021	2020
Risk free interest rate	0.04% - 0.10%	0.10% - 0.18%
Expected term (in years)	0.5 years	0.5 years
Dividend yield	—	—
Expected volatility	60.46% - 131.21%	74.36% - 120.89%

Schedule of Stock Option Activity

The following table summarizes stock option activity for employees and non-employees:


	Number of Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2020	9,591,123	$	3.44		$	2,303
Granted	2,822,696	3.05			—
Exercised	482,115	2.14			1,106
Canceled	379,991	4.96			102
Outstanding, December 31, 2021	11,551,713	$	3.34	6.71 years	$	11,402
Vested or expected to vest, December 31, 2021	11,551,713	$	3.34	6.71 years	$	11,402
Exercisable, December 31, 2021	7,376,177	$	3.45	5.52 years	$	7,964

The following table summarizes stock option activity for these inducement options (in thousands):


	Number of Options	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Life	Aggregate Intrinsic Value (in thousands)
Outstanding, December 31, 2020	420,313	$	5.00		$	—
Granted	360,000	$	3.48		$	—
Canceled or Expired	120,313	$	5.87		$	—
Outstanding, December 31, 2021	660,000	$	4.01	8.71 years	$	108
Vested or expected to vest, December 31, 2021	660,000	$	4.01	8.71 years	$	108
Exercisable, December 31, 2021	168,750	$	4.65	7.66 years	$	—

Schedule of Stock-Based Compensation Expense

Total stock-based compensation expense is recorded in operating expenses based upon the functional responsibilities of the individuals holding the respective options as follows (in thousands):


	Years Ended December 31,
	2021		2020
Research and development	$	2,274	$	2,394
General and administrative	2,941		2,696
Total stock-based compensation	$	5,215	$	5,090

Leases (Tables)

12 Months Ended

Dec. 31, 2021

Leases [Abstract]

Lease Costs, Term and Discount Rate

The following table summarizes operating lease costs included in operating expenses (in thousands):


	Years Ended December 31,
	2021		2020
Operating lease costs	$	1,483	$	1,509
Variable lease costs (1)	739		708
Total lease cost	$	2,222	$	2,217
(1) Variable lease costs include certain additional charges for operating costs, including insurance, maintenance, taxes, utilities, and other costs incurred, which are billed based on both usage and as a percentage of the Company’s share of total square footage.

The following table summarizes the weighted-average remaining lease term and discount rate:


	As of December 31,
	2021		2020
Weighted-average remaining lease term (years)	10.4		11.4
Weighted-average discount rate	10.5	%	10.5	%

Maturities of Operating Lease Liabilities

As of December 31, 2021, the maturities of the Company’s operating lease liabilities and future minimum lease payments were as follows (in thousands):


	Total
2022	$	2,474
2023	2,235
2024	2,235
2025	2,235
2026	2,235
Thereafter	12,482
Total undiscounted lease payments	23,896
Less: present value adjustment	(9,006)
Present value of lease liabilities	14,890

Corporate Information - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2014
Subsequent Event [Line Items]
Cash and cash equivalents	$ 117,764	$ 70,436
Net loss	(45,738)	(37,230)
Accumulated deficit	$ (257,144)	$ (211,406)
Pieris Pharmaceuticals GmbH
Subsequent Event [Line Items]
Ownership interest acquired (as a percent)			100.00%

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References + Details

Summary of Significant Accounting Policies - Narrative (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Accounting Policies [Abstract]
Allowance for doubtful accounts	$ 0	$ 0

Summary of Significant Accounting Policies - Estimated Useful Life of Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2021
Laboratory furniture and equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	8 years
Laboratory furniture and equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	14 years
Office furniture and equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Office furniture and equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	13 years
Computer and equipment \| Minimum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Computer and equipment \| Maximum
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years

Revenue - Revenue from Strategic Partnerships and Other License Agreements (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenues		$ 31,418	$ 29,323
AstraZeneca
Disaggregation of Revenue [Line Items]
Revenues	$ 13,000	18,919	8,308
Seagen
Disaggregation of Revenue [Line Items]
Revenues		768	9,702
Servier
Disaggregation of Revenue [Line Items]
Revenues		4,070	11,313
Boston Pharmaceuticals
Disaggregation of Revenue [Line Items]
Revenues		5,711	0
Genentech
Disaggregation of Revenue [Line Items]
Revenues		$ 1,950	$ 0

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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+ Details

Revenue - Potential Milestone Payments (Details) - Strategic Partnerships and Other License Agreements - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Research, Development, Regulatory & Commercial Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments	$ 2,918
Sales Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments		$ 5,692
AstraZeneca \| Research, Development, Regulatory & Commercial Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments	1,096
AstraZeneca \| Sales Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments		4,275
Servier \| Research, Development, Regulatory & Commercial Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments	136
Servier \| Sales Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments		102
Seagen \| Research, Development, Regulatory & Commercial Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments	754
Seagen \| Sales Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments		450
Boston Pharmaceuticals \| Research, Development, Regulatory & Commercial Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments	88
Boston Pharmaceuticals \| Sales Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments		265
Genentech \| Research, Development, Regulatory & Commercial Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments	$ 844
Genentech \| Sales Milestones
Revenue Recognition, Milestone Method [Line Items]
Total potential milestone payments		$ 600

Revenue - Narrative (Details) $ / shares in Units, $ in Thousands, € in Millions																									1 Months Ended			3 Months Ended		12 Months Ended
	May 19, 2021 USD ($)	May 19, 2021 USD ($)	May 19, 2021 USD ($) lease_agreement	May 19, 2021 USD ($) performance_obligation	May 19, 2021 USD ($) program	Apr. 24, 2021 USD ($)	Apr. 01, 2021 USD ($) $ / shares shares	Mar. 29, 2021 shares	Mar. 24, 2021 USD ($) $ / shares shares	Feb. 08, 2018 USD ($) performance_obligation program research_program license swap_option	May 02, 2017 USD ($)	May 02, 2017 USD ($)	May 02, 2017 USD ($) lease_agreement	May 02, 2017 USD ($) performance_obligation	May 02, 2017 USD ($) research_program	May 02, 2017 USD ($) license	May 02, 2017 USD ($) protein	Jan. 04, 2017 collaboration_product product	Jan. 04, 2017 USD ($) collaboration_product product	Jan. 04, 2017 performance_obligation collaboration_product product	Jan. 04, 2017 program collaboration_product product	Jan. 04, 2017 license collaboration_product product	Jan. 04, 2017 collaboration_product bispecific_therapeutic_program product	Jan. 04, 2017 EUR (€) collaboration_product product	Mar. 31, 2021 USD ($)	Feb. 28, 2021	Feb. 29, 2020 program collaboration_product	Mar. 31, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2021 USD ($) performance_obligation	Dec. 31, 2021 EUR (€) performance_obligation	Dec. 31, 2020 USD ($)	Jan. 01, 2019 USD ($)	May 02, 2017 lease_agreement	May 02, 2017 performance_obligation	May 02, 2017 collaboration_product
Disaggregation of Revenue [Line Items]
Deferred revenues, current portion																														$ 25,116		$ 12,627
Deferred revenue, net of current portion																														38,403		35,900
Revenue recognized from contract with customer																														11,000
Number of technology licenses (in licenses) \| lease_agreement													5
Revenues																														31,418		29,323
Number of separate performance obligations (in performance obligations) \| performance_obligation																				1
Amortization of capitalized contract costs																																100
Additions to contract with customer, liability																														31,600
Genentech
Disaggregation of Revenue [Line Items]
Fee on additional program		$ 10,000
Termination notice period within material breach	90 days
Before first commercial sale	90 days
After first commercial sale	180 days
Number of research programs			4		2
Remaining performance obligation																														16,600
Revenues																														1,950		0
Genentech \| License fees
Disaggregation of Revenue [Line Items]
Deferred revenue	$ 20,000	$ 20,000	$ 20,000	$ 20,000	$ 20,000
Deferred revenues, current portion																														8,100
Deferred revenue, net of current portion																														8,500
Genentech \| Research and development services
Disaggregation of Revenue [Line Items]
Research collaboration agreement term	3 years
Boston Pharmaceuticals \| License fees
Disaggregation of Revenue [Line Items]
Remaining performance obligation						$ 6,000
Contract with customer asset, after allowance for credit loss						4,000
Seagen
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation										3
Remaining performance obligation																														21,500
Deferred revenues, current portion																														10,300
Deferred revenue, net of current portion																														8,200
Amended collaboration agreement, resale of stock, period									60 days
Revenues																														768		9,702
Seagen \| Private Placement
Disaggregation of Revenue [Line Items]
Deferred revenue									$ 3,300
Shares of common stock issued (shares) \| shares									3,706,174
Net proceeds from private placement									$ 13,000
Issue price per share (USD per share) \| $ / shares									$ 3.51
Fair value of stock (in dollars per share) \| $ / shares									$ 2.61
AstraZeneca
Disaggregation of Revenue [Line Items]
Deferred revenue																														700
Research collaboration agreement term											5 years
Remaining performance obligation																														18,700
Deferred revenues, current portion																														900
Deferred revenue, net of current portion																														17,000
Revenues																									$ 13,000					18,919		8,308
AstraZeneca \| Private Placement
Disaggregation of Revenue [Line Items]
Shares of common stock issued (shares) \| shares							3,584,230	3,584,230
Net proceeds from private placement							$ 10,000
Issue price per share (USD per share) \| $ / shares							$ 2.79
Fair value of stock (in dollars per share) \| $ / shares							$ 2.60
Servier
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation																				10
Remaining performance obligation																														10,400
Deferred revenues, current portion																														5,800
Deferred revenue, net of current portion																														4,600
Revenue recognized from contract with customer																													$ 7,100
Number of novel proteins (in proteins) \| bispecific_therapeutic_program																							1
Number of research programs (in research programs)																					3		3				5
Revenues																														4,070		11,313
Capitalized contract cost, net																														$ 100
Research term extension period																										12 months	12 months
Number of separate performance obligations (in performance obligations) \| performance_obligation																				2
Number of combined performance obligations (in obligations) \| performance_obligation																				2
Number of preclinical stage programs (in programs) \| program																											2
Period to complete remaining obligations on programs																											60 days
Servier \| Research and development services
Disaggregation of Revenue [Line Items]
Research collaboration agreement term																		3 years
Number of development milestones \| performance_obligation																														4	4
License and collaboration agreement \| Genentech
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation				5
License and collaboration agreement \| Seagen
Disaggregation of Revenue [Line Items]
Number of research programs \| research_program										3
Number of performance obligations \| performance_obligation										6
Period after effective date agreements may be terminated										12 months
Contract termination advance notice period										90 days
Agreement termination advance notice period if marketing approval obtained										180 days
Agreement termination notice period upon material breach by the Company										90 days
Contract termination due to material breach, additional notice period if the breach is not susceptible										90 days
Number of licenses \| license										3
Number of Swap options \| swap_option										2
License and collaboration agreement \| AstraZeneca
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation														16
Period after effective date agreements may be terminated											12 months
Contract termination advance notice period											90 days
Agreement termination advance notice period if marketing approval obtained											180 days
Agreement termination notice period upon material breach by the Company											180 days
Contract termination due to material breach, additional notice period if the breach is not susceptible											180 days
Number of novel proteins (in proteins) \| protein																	4
Agreement termination notice period upon breach of payment obligations by the Company											30 days
Period of license performance obligation											12 months
Revenues																														$ 13,000
License and collaboration agreement \| Servier
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation																				4
Number of licenses \| license																						5
Number of collaboration products (in collaboration products) \| collaboration_product																		2	2	2	2	2	2	2
Number of research programs (in research programs) \| bispecific_therapeutic_program																							5
Collaborative arrangement \| Servier
Disaggregation of Revenue [Line Items]
Period after effective date agreements may be terminated																		12 months
Revenue recognized from contract with customer																														4,300	€ 3.8
Contract termination advance notice period																		180 days
Number of collaboration products (in collaboration products) \| product																		4	4	4	4	4	4	4
Co-development collaboration product \| Servier
Disaggregation of Revenue [Line Items]
Number of collaboration products (in collaboration products) \| collaboration_product																											1
Servier developed collaboration product \| Servier
Disaggregation of Revenue [Line Items]
Number of collaboration products (in collaboration products) \| collaboration_product																											1
Other arrangement \| Seagen
Disaggregation of Revenue [Line Items]
Number of research programs \| research_program										2
Platform technology license \| Genentech
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation				2
Number of target programs \| program					2
Platform technology license \| Seagen
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation										3
Number of target programs \| program										3
Antibody target swap \| Genentech
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation				2
Antibody target swap \| Seagen
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation										2
Governance committee participation \| Genentech
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation				1
Governance committee participation \| Seagen
Disaggregation of Revenue [Line Items]
Number of performance obligations \| performance_obligation										1
Upfront payment \| Boston Pharmaceuticals \| License fees
Disaggregation of Revenue [Line Items]
Remaining performance obligation						10,000
Upfront payment \| Seagen
Disaggregation of Revenue [Line Items]
Research and development services										$ 4,900
Upfront payment \| Seagen \| License fees
Disaggregation of Revenue [Line Items]
Revenue										$ 30,000
Upfront payment \| AstraZeneca
Disaggregation of Revenue [Line Items]
Allocable arrangement consideration												$ 45,000
Upfront payment \| Servier \| License fees
Disaggregation of Revenue [Line Items]
Revenue																			$ 32,000					€ 30.0
Additional other research services \| AstraZeneca
Disaggregation of Revenue [Line Items]
Allocable arrangement consideration												4,700
Exclusive Product License Agreement \| Boston Pharmaceuticals \| License fees
Disaggregation of Revenue [Line Items]
Deferred revenue						10,000
Remaining performance obligation																														5,700
Contribution on manufacturing (up to)						$ 4,000
Period after effective date agreements may be terminated						9 months
Contract termination advance notice period						60 days
Agreement termination advance notice period if marketing approval obtained						120 days
Agreement termination notice period upon material breach by the Company						180 days
Agreement termination notice period due to non-payment of undisputed amounts						60 days
Contract termination due to material breach, additional notice period if the breach is not susceptible						180 days
Collaborative arrangement, agreement obligation cost						$ 4,000
Estimated development and manufacturing services \| Upfront payment \| AstraZeneca
Disaggregation of Revenue [Line Items]
Allocable arrangement consideration												14,200
Milestone payments \| Upfront payment \| Seagen
Disaggregation of Revenue [Line Items]
Revenue recognized from contract with customer																												$ 4,200
Allocable arrangement consideration																													$ 5,000
Milestone payments \| Upfront payment \| AstraZeneca
Disaggregation of Revenue [Line Items]
Allocable arrangement consideration												12,500
Estimated phase 2a services \| Upfront payment \| AstraZeneca
Disaggregation of Revenue [Line Items]
Allocable arrangement consideration												4,700
Agreement extension options \| Servier \| Research and development services
Disaggregation of Revenue [Line Items]
Research collaboration agreement term																		1 year
Number of agreement extension options (extension options) \| performance_obligation																				2
Minimum \| License and collaboration agreement \| AstraZeneca
Disaggregation of Revenue [Line Items]
Number of collaboration products (in collaboration products) \| collaboration_product																																				2
Minimum \| Collaborative arrangement \| Servier
Disaggregation of Revenue [Line Items]
Agreement termination notice period upon material breach by the Company																		90 days
Maximum \| License and collaboration agreement \| AstraZeneca
Disaggregation of Revenue [Line Items]
Number of collaboration products (in collaboration products)																		4	4	4	4	4	4	4										4	4	4
Number of research programs (in research programs) \| research_program															2
Number of research licenses (in licenses)													4			4						4
Maximum \| Collaborative arrangement \| Servier
Disaggregation of Revenue [Line Items]
Agreement termination notice period upon material breach by the Company																		120 days
Accounting Standards Update 2014-09 \| AstraZeneca
Disaggregation of Revenue [Line Items]
Capitalized contract cost, net											$ 1,600	$ 1,600	$ 1,600	$ 1,600	$ 1,600	$ 1,600	$ 1,600													$ 600		$ 600
Capitalized contract cost in accordance with ASC 340																																	$ 1,100
Accounting Standards Update 2014-09 \| Servier
Disaggregation of Revenue [Line Items]
Capitalized contract cost, net																																	$ 500

Collaboration agreements (Details) - Lilly - Collaborative arrangement	Aug. 10, 2020
Other Commitments [Line Items]
Termination notice period	60 days
Period to propose modifications	15 days

Grant Income (Details) - Dec. 31, 2021 € in Millions, $ in Millions	USD ($)	EUR (€)
Receivables [Abstract]
Grants receivable	$ 17.0	€ 14.2

Cash, Cash Equivalents and Investments - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Realized gains (losses) recognized on available-for-sale investments	$ 0	$ (600,000)
Money market funds \| Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	$ 56,900,000	$ 64,000,000

Property and Equipment, Net - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment at cost	$ 26,839	$ 27,861
Accumulated depreciation	(7,717)	(5,815)
Property and equipment, net	19,122	22,046
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment at cost	13,130	14,159
Laboratory equipment
Property, Plant and Equipment [Line Items]
Property and equipment at cost	11,354	11,188
Office furniture and equipment
Property, Plant and Equipment [Line Items]
Property and equipment at cost	1,959	2,120
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment at cost	$ 396	$ 394

Property and Equipment, Net - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Depreciation expense	$ 2.4	$ 2.1

Accrued Expenses - Summary (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accrued expenses
Research and development fees	$ 5,682	$ 2,001
Compensation expense	3,581	2,759
Accrued accounts payable	2,980	1,220
Collaboration cost-sharing obligation	1,610	16
Accrued license obligations	1,541	358
Lease liabilities	1,049	1,030
Other current liabilities	393	347
Total	$ 16,836	$ 7,731
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Total	Total

Income Taxes - Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Domestic	$ (11,312)	$ (12,134)
Foreign	(34,426)	(24,932)
Loss before income taxes	$ (45,738)	$ (37,066)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 32
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8933-108599

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=123384075&loc=d3e41242-110953

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8736-108599

Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(10))
-URI http://asc.fasb.org/extlink&oid=123367319&loc=SL114868664-224227

Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(8))
-URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-URI http://asc.fasb.org/extlink&oid=120399901&loc=d3e537907-122884

Reference 9: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 31
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8924-108599

Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(15))
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

+ Details

Income Taxes - Components of the Provision (Benefit) for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Current:
Federal	$ 0	$ 0
State	0	0
Foreign	0	164
Total current	0	164
Deferred:
Federal	0	0
State	0	0
Foreign	0	0
Total deferred	0	0
Provision for income taxes	$ 0	$ 164

Income Taxes - Reconciliation of Federal Statutory Rate to the Effective Tax Rate (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Federal income tax rate	21.00%	21.00%
Foreign rate differential	5.60%	1.90%
State tax, net of federal benefit	1.20%	1.90%
US tax on foreign income	0.00%	0.00%
Share-based awards compensation	(3.50%)	(3.80%)
Permanent items	(0.20%)	(2.40%)
Provision to return	3.30%	0.00%
Other	0.00%	(0.40%)
Change in valuation allowance	(27.40%)	(18.70%)
Effective income tax rate	0.00%	(0.50%)

Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Net operating loss carryforwards	$ 49,280	$ 39,175
Share-based awards compensation	2,739	2,913
Accrued expenses	323	230
Depreciation and other	384	297
Unrealized foreign currency	256	771
Lease liability	4,022	4,582
Total deferred tax assets	57,004	47,968
Deferred tax liabilities:
Right-of-use asset	(3,729)	(4,235)
Accrued expenses	(68)	0
Total deferred tax liabilities	(3,797)	(4,235)
Less: valuation allowance:	(53,207)	(43,733)
Net deferred tax asset	$ 0	$ 0

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
Income Taxes - Narrative (Details) - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Income Taxes [Line Items]
Increase in the valuation allowance	$ 9,500,000
Uncertain tax positions interest and penalties accrued	0	$ 0
Federal
Income Taxes [Line Items]
Net operating loss carryforwards	33,100,000
State
Income Taxes [Line Items]
Net operating loss carryforwards	37,400,000
Germany
Income Taxes [Line Items]
Net operating loss carryforwards	1,200,000
Germany \| Corporate income tax carryforwards
Income Taxes [Line Items]
Net operating loss carryforwards	154,800,000
Germany \| Trade tax carryforwards
Income Taxes [Line Items]
Net operating loss carryforwards	$ 153,900,000

Income Taxes - Reconciliation of Unrecognized Tax Benefits Excluding Impact of Interest and Penalties (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning balance	$ 6,135
Currency translation adjustment	(470)
Unrecognized tax benefits, ending balance	$ 5,665

Stockholders' equity - Narrative (Details) $ / shares in Units, $ in Thousands				1 Months Ended				12 Months Ended
	May 20, 2021 performance_obligation $ / shares shares	Apr. 01, 2020 shares	Jan. 30, 2019 shares	Aug. 31, 2021 USD ($) $ / shares	Nov. 30, 2019 USD ($) $ / shares shares	Aug. 31, 2019 USD ($)	Jun. 30, 2016 USD ($) shares	Dec. 31, 2021 USD ($) vote $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Jun. 30, 2017 $ / shares
Class of Stock [Line Items]
Common stock, shares authorized (shares)								300,000,000	300,000,000
Common stock, shares outstanding (shares)								72,222,661	56,002,815
Common stock, shares issued (shares)								72,222,661	56,002,815
Common Stock, Par or Stated Value Per Share \| $ / shares				$ 0.001				$ 0.001	$ 0.001
Preferred stock, shares authorized (shares)								10,000,000	10,000,000
Preferred stock, shares outstanding (shares)								15,617	14,429
Preferred stock, shares issued (shares)								15,617	14,429
Preferred stock, par value (USD per share) \| $ / shares								$ 0.001	$ 0.001
Number of classes of preferred stock \| performance_obligation	5
Gross proceeds from private placement units sold \| $								$ 18,913	$ 0
Gross sales proceeds from common stock \| $						$ 50,000		$ 38,188	$ 9,624
At the market offering
Class of Stock [Line Items]
Shares of common stock issued (shares)								8,200,000	3,600,000
Issue price per share (USD per share) \| $ / shares									$ 2.80
Net proceeds from underwritten public offering \| $									$ 10,000
Sale of stock, authorized amount \| $				$ 50,000
Securities Purchase Agreement
Class of Stock [Line Items]
Number of capital units sold in private placement transaction (in shares)							8,188,804
Gross proceeds from private placement units sold \| $							$ 16,500
Net proceeds from private placement units sold \| $							$ 15,300
Two Thousand And Sixteen Private Investment In Public Equity
Class of Stock [Line Items]
Shares of common stock issued (shares)							3,225,804
At The Market Offering 1
Class of Stock [Line Items]
Issue price per share (USD per share) \| $ / shares								$ 4.85
Net proceeds from underwritten public offering \| $								$ 39,700
Common shares
Class of Stock [Line Items]
Number of votes per share \| vote								1
Number of shares per unit (shares)								3,812,000
Common shares \| Stock Exchange, Shares from Existing Shareholders
Class of Stock [Line Items]
Shares of common stock issued (shares)	5,000,000	3,000,000	5,000,000
Convertible preferred shares
Class of Stock [Line Items]
Number of shares per unit (shares)								(4,000)
Convertible preferred shares \| Preferred Share Exchange
Class of Stock [Line Items]
Shares of common stock issued (shares)		3,000	5,000
Series A Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares outstanding (shares)								85	2,907
Preferred stock, shares issued (shares)								85	2,907
Price per unit issued (USD per share) \| $ / shares										$ 2.015
Series A Convertible Preferred Stock \| Private Placement \| Two Thousand And Sixteen Private Investment In Public Equity
Class of Stock [Line Items]
Preferred stock, shares issued (shares)							4,963
Series B Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares outstanding (shares)								4,026	5,000
Preferred stock, shares issued (shares)								4,026	5,000
Series C Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares outstanding (shares)								3,506	3,522
Preferred stock, shares issued (shares)								3,506	3,522
Series C Convertible Preferred Stock \| Preferred Share Exchange
Class of Stock [Line Items]
Issue price per share (USD per share) \| $ / shares					$ 3.43
Beneficial conversion feature \| $					$ 2,800
Series C Convertible Preferred Stock \| Private Placement
Class of Stock [Line Items]
Shares issued upon conversion of convertible preferred stock (shares)					0.001
Effective period of change to beneficial ownership limitation					60 days
Shares of common stock issued (shares)					9,014,960
Number of shares per unit (shares)					1
Number of shares called by each warrant (in shares)					1
Exercise price (USD per share) \| $ / shares					$ 7.10
Issue price per share (USD per share) \| $ / shares					$ 3.55
Shares of stock sold, gross consideration \| $					$ 32,000
Net proceeds from underwritten public offering \| $					$ 31,000
Number of warrants included with each unit (in shares)					1
Period of determining volume weighted average stock price					10 days
Weighted average stock price commencing on trading day					3.00%
Series C Convertible Preferred Stock \| Private Placement \| Maximum
Class of Stock [Line Items]
Warrants and rights outstanding, term					5 years
Series D Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares outstanding (shares)								3,000	3,000
Preferred stock, shares issued (shares)								3,000	3,000
Series E Convertible Preferred Stock
Class of Stock [Line Items]
Preferred stock, shares outstanding (shares)								5,000	0
Preferred stock, shares issued (shares)								5,000	0
Series E Convertible Preferred Stock \| Convertible preferred shares \| Preferred Share Exchange
Class of Stock [Line Items]
Shares of common stock issued (shares)	5,000
Series A through Series E \| Convertible preferred shares
Class of Stock [Line Items]
Preferred stock, par value (USD per share) \| $ / shares	$ 0.001
Shares issued upon conversion of convertible preferred stock (shares)	1,000
Common stock ownership limit (as a percent)	9.99%
Beneficial ownership limitation (as a percent)	19.99%
Effective period of change to beneficial ownership limitation	61 days

Net Loss per Share - Narrative (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Earnings Per Share [Abstract]
Anti-dilutive stock excluded from calculation of weighted average shares outstanding (shares)	36.8	37.0

Stock and Employee Benefit Plans - Narrative (Details) $ / shares in Units, $ in Millions		12 Months Ended
	Jun. 23, 2020 shares	Dec. 31, 2021 USD ($) purchasePeriod $ / shares shares	Dec. 31, 2020 $ / shares shares	Jun. 25, 2021 shares
Defined Benefit Plan Disclosure [Line Items]
Number of options granted (shares)		3,182,696	2,311,481
Weighted-average fair value (USD per share) \| $ / shares		$ 2.04	$ 1.92
Issuance of common stock resulting from purchase of employee stock purchase plan shares (shares)		64,257	69,544
Unrecognized compensation costs related to nonvested awards \| $		$ 8.1
Weighted-average compensation cost recognition period		2 years 7 months 20 days
2020 Plan
Defined Benefit Plan Disclosure [Line Items]
Common stock authorized for issuance (shares)	3,500,000			5,750,000
Additional shares reserved for future issuance (shares)				2,250,000
Maximum term of stock options		10 years
Number of options granted (shares)		2,822,696
2019 Plan
Defined Benefit Plan Disclosure [Line Items]
Shares available for grant under prior plan (shares)	1,579,678
Stock available for future grant (shares)		3,282,399
Executive Officers and Senior Leadership
Defined Benefit Plan Disclosure [Line Items]
Number of options granted (shares)		360,000
Unrecognized compensation costs related to nonvested awards \| $		$ 1.2
Employee Stock
Defined Benefit Plan Disclosure [Line Items]
Common stock authorized for issuance (shares)		500,000
Discount from market price (as a percent)		85.00%
Number of purchase periods \| purchasePeriod		2
Term of purchase period		6 months

Stock and Employee Benefit Plans - Fair Value Assumptions (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free interest rate, minimum (as a percent)	0.46%	0.33%
Risk free interest rate, maximum (as a percent)	1.20%	1.53%
Dividend yield (as a percent)	0.00%	0.00%
Expected volatility, minimum (as a percent)	75.00%	70.00%
Expected volatility, maximum (as a percent)	81.70%	75.80%
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 3 months 21 days	5 years
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)	5 years 8 months 23 days	5 years 8 months 23 days
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free interest rate, minimum (as a percent)	0.04%	0.10%
Risk free interest rate, maximum (as a percent)	0.10%	0.18%
Expected term (in years)	6 months	6 months
Dividend yield (as a percent)	0.00%	0.00%
Expected volatility, minimum (as a percent)	60.46%	74.36%
Expected volatility, maximum (as a percent)	131.21%	120.89%

Stock and Employee Benefit Plans - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Number of Options
Granted (shares)	3,182,696	2,311,481
Executive Officers and Senior Leadership
Number of Options
Outstanding (shares)	420,313
Granted (shares)	360,000
Canceled (shares)	120,313
Outstanding (shares)	660,000	420,313
Vested or expected to vest (shares)	660,000
Exercisable (shares)	168,750
Weighted- Average Exercise Price
Outstanding (USD per share)	$ 5.00
Granted (USD per share)	3.48
Canceled (USD per share)	5.87
Outstanding (USD per share)	4.01	$ 5.00
Vested or expected to vest (USD per share)	4.01
Exercisable (USD per share)	$ 4.65
Weighted- Average Remaining Contractual Life
Outstanding	8 years 8 months 15 days
Vested or expected to vest	8 years 8 months 15 days
Exercisable	7 years 7 months 28 days
Aggregate Intrinsic Value (in thousands)
Outstanding	$ 0
Granted	0
Canceled	0
Outstanding	108	$ 0
Vested or expected to vest	108
Exercisable	$ 0
2020 Plan
Number of Options
Outstanding (shares)	9,591,123
Granted (shares)	2,822,696
Exercised (shares)	482,115
Canceled (shares)	379,991
Outstanding (shares)	11,551,713	9,591,123
Vested or expected to vest (shares)	11,551,713
Exercisable (shares)	7,376,177
Weighted- Average Exercise Price
Outstanding (USD per share)	$ 3.44
Granted (USD per share)	3.05
Exercised (USD per share)	2.14
Canceled (USD per share)	4.96
Outstanding (USD per share)	3.34	$ 3.44
Vested or expected to vest (USD per share)	3.34
Exercisable (USD per share)	$ 3.45
Weighted- Average Remaining Contractual Life
Outstanding	6 years 8 months 15 days
Vested or expected to vest	6 years 8 months 15 days
Exercisable	5 years 6 months 7 days
Aggregate Intrinsic Value (in thousands)
Outstanding	$ 2,303
Granted	0
Exercised	1,106
Canceled	102
Outstanding	11,402	$ 2,303
Vested or expected to vest	11,402
Exercisable	$ 7,964

Stock and Employee Benefit Plans - Stock Based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 5,215	$ 5,090
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	2,274	2,394
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 2,941	$ 2,696

Leases - Narrative (Details) $ in Millions	1 Months Ended			3 Months Ended	12 Months Ended
Leases - Narrative (Details) $ in Millions	May 31, 2020 ft²	Feb. 29, 2020 USD ($) ft²	Aug. 31, 2015 ft²	Mar. 31, 2020 ft² lease_agreement floor	Dec. 31, 2021 USD ($) ft² extension_option	Dec. 31, 2020 USD ($)	Jul. 31, 2021	Mar. 31, 2019 USD ($)
Loss Contingencies [Line Items]
Lease liabilities \| $					$ 2.6	$ 2.2
Boston, Massachusetts
Loss Contingencies [Line Items]
Area of leased property (square feet)			3,950
Lease renewal term							10 months
Hallbergmoos, Germany
Loss Contingencies [Line Items]
Area of leased property (square feet)		105,000
Lease renewal term					60 months
Lease term		12 years 6 months
Number of agreement extension options (extension options) \| extension_option					2
Rent expense \| $		$ 0.2
Security deposit \| $		$ 0.8
Tenant Improvements \| $								$ 11.5
Freising, Germany
Loss Contingencies [Line Items]
Area of leased property (square feet)				19,000
Number of lease agreements (lease agreements) \| lease_agreement				4
Leases expected to be delivered by February 2020 \| Hallbergmoos, Germany
Loss Contingencies [Line Items]
Area of leased property (square feet)		96,400
Leases expected to be delivered by May 2020 \| Hallbergmoos, Germany
Loss Contingencies [Line Items]
Area of leased property (square feet)	8,600
Leases expected to be delivered by October 2024 \| Hallbergmoos, Germany
Loss Contingencies [Line Items]
Area of leased property (square feet)					22,300
Leases with first right of refusal for additional area \| Hallbergmoos, Germany
Loss Contingencies [Line Items]
Area of leased property (square feet)					13,400
Leases in same building \| Freising, Germany
Loss Contingencies [Line Items]
Number of lease agreements (lease agreements) \| lease_agreement				3
Number of floors (in floors) \| floor				3

Leases - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
Leases - Lease Cost (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Operating lease costs	$ 1,483	$ 1,509
Variable lease costs	739	708
Total lease cost	$ 2,222	$ 2,217

Leases - Summary of the Lease Term and Discount Rate (Details)	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Weighted-average remaining lease term (years)	10 years 4 months 24 days	11 years 4 months 24 days
Weighted-average discount rate	10.50%	10.50%

Leases - Maturities of Operating Lease Liabilities (Details) $ in Thousands	Dec. 31, 2021 USD ($)
Leases [Abstract]
2022	$ 2,474
2023	2,235
2024	2,235
2025	2,235
2026	2,235
Thereafter	12,482
Total undiscounted lease payments	23,896
Less: present value adjustment	(9,006)
Present value of lease liabilities	$ 14,890