0001437749-23-031957 | 10-Q | XBRL Viewer | Pieris Pharmaceuticals INC

Accounts Payable and Accrued Liabilities Disclosure [Text Block]

7. Accrued Expenses

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

	*September 30,*		*December 31,*
	*2023*		*2022*
Compensation expense	$	8,735	$	3,015
Research and development fees		1,971		5,758
Accrued accounts payable		1,348		1,245
Other current liabilities		575		483
Accrued license obligations		135		245
Total	$	12,764	$	10,746

The compensation expense line item in the above table includes both severance and retention costs associated with the Company's recently announced corporate restructuring. The Company recognized restructuring expenses consisting of one-time cash severance payments and other employee-related costs of $6.8 million during the three and nine months ended September 30, 2023. Severance pay and related costs for currently retained employees are estimated to be paid through the second quarter of 2024. The Company recorded these restructuring charges based on each employee’s role to the respective research and development and general and administrative operating expense categories on its condensed consolidated statements of operations and comprehensive loss.

Note 7 - Accrued Expenses (Details Textual) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2023
One-time Cash Severance Payment and Other Employee Related Costs [Member]
Restructuring Costs	$ 6.8	$ 6.8

Note 6 - Assets Held for Sale, Property and Equipment

9 Months Ended

Sep. 30, 2023

Assets Held for Sale and Property, Plant and Equipment Disclosure [Text Block]

6. Assets Held for Sale, Property and Equipment

As of December 31, 2022, property and equipment are summarized as follows (in thousands):

	December 31,
	2022
Laboratory furniture and equipment	$	11,970
Office furniture and equipment		1,861
Computer equipment		364
Leasehold improvements		12,444
Property and equipment, cost		26,639
Accumulated depreciation		(9,647	)
Property and equipment, net	$	16,992

As of September 30, 2023, assets held for sale are summarized as follows (in thousands):

	*September 30,*
	*2023*
Laboratory furniture and equipment	$	1,887
Office furniture and equipment		211
Assets held for sale, property and equipment	$	2,098

At the end of the third quarter of 2023, as part of the Company's strategic process for maximizing the value of assets, the Company committed to a plan to prepare and sell all property and equipment held at the Hallbergmoos, Germany location. The Company engaged Stifel to assist with a process to locate a buyer alongside internal efforts to sell the majority of property and equipment held there. The sale of the assets was deemed probable as a result of management's decision, including the estimated timing of sale which was determined to be within a year of the decision. Given the ongoing strategic review, it is unlikely that significant change to the plan will occur. As a result of this decision, the property and equipment met the criteria for held-for-sale accounting as of September 30, 2023. The Company is in the process of obtaining third-party appraisals for the resale value of equipment to be disposed and expects substantially all assets to be disposed by the end of the first quarter of 2024.

The Company recorded impairment charges totaling $14.9 million, of which $1.8 million related to impairment of its right-of-use asset under the Hallbergmoos Lease (see Note 10) with the remaining related to a complete write-off of leasehold improvements and a partial impairment of the Company's other long-lived assets.. The remaining $2.1 million in net book value of its long-lived assets represents the Company's best estimate of the fair value less costs to sell that could be recovered related to lab equipment and furniture as part of the Company's initiative to monetize all remaining assets. As the estimated selling price less costs to sell are based primarily on unobservable inputs as they relate to the location and condition of the specific lab equipment and furniture, they are classified in Level 3 in the fair value heirarchy.

Condensed Consolidated Statements of Cash Flows (Unaudited) (Parentheticals) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Stock issuance costs	$ 0.7	$ 0.3

Note 10 - Leases

9 Months Ended

Sep. 30, 2023

Lessee, Operating Leases [Text Block]

10. Leases

In August 2015, the Company entered into a sublease to lease approximately 3,950 square feet of office space in Boston, Massachusetts. The Company did not extend the sublease, which expired on December 31, 2022.

In October 2018, Pieris Pharmaceuticals GmbH entered into a new lease for office and laboratory space located in Hallbergmoos, Germany, or the Hallbergmoos Lease. The Hallbergmoos Lease was subsequently amended in May 2019 and February 2020. The Hallbergmoos Lease, as amended, provides an initial rental term of 12.5 years, and a rental area of approximately 105,000 square feet.

Monthly base rent for the initial 105,000 square feet of the leased property, including parking spaces, totaled approximately $0.2 million per month. In addition to the base rent, Pieris Pharmaceuticals GmbH was also responsible for certain administrative and operational costs in accordance with the Hallbergmoos Lease. Pieris Pharmaceuticals GmbH provided a security deposit of $0.8 million as required by the Hallbergmoos Lease. The Company serves 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 condensed consolidated balance sheet and are amortized on a straight-line basis over the shorter of the useful life or the remaining lease term. As part of the strategic review the Company is undertaking, along with the announced workforce restructuring, the Company is evaluating its options to exit the Hallbergmoos Lease. Included in the impairment charges recorded during the third quarter ended September 30, 2023, is a write-down of the entire amount of the leasehold improvement and an impairment of the right of use asset associated with the Hallbergmoos Lease of $1.8 million.

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

	*Three Months Ended September 30,*				*Nine Months Ended September 30,*
	*2023*		*2022*		*2023*		*2022*
Operating lease costs	$	280	$	314	$	862	$	943
Variable lease costs (1)		98		148		476		446
Total lease cost	$	378	$	462	$	1,338	$	1,389

(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 September 30, 2023*
Weighted-average remaining lease term (years)		8.8
Weighted-average discount rate		10.5	%

Cash paid for amounts included in the measurement of the lease liabilities were $0.5 million for both the three months ended September 30, 2023 and 2022. Cash paid for amounts included in the measurement of the lease liabilities were $1.6 million and for both the nine months ended September 30, 2023 and 2022.

As of September 30, 2023, the maturities of the Company’s operating lease liabilities and future minimum lease payments were as follows (in thousands):

	*Total*
2023	$	522
2024		2,087
2025		2,087
2026		2,087
2027		2,087
Thereafter		9,565
Total undiscounted lease payments		18,435
Less: present value adjustment		(6,142	)
Present value of lease liabilities	$	12,293

Not included in the above table are amounts to be paid for the Hallbergmoos Lease expansion that were expected to commence in October 2024 under the Hallbergmoos Lease. This amount is estimated to be $3.9 million in aggregate for the period of October 2024 through the end of the lease term.

Note 5 - Cash, Cash Equivalents and Investments - Cash Equivalents and Investments Carried at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value	$ 11,916
Total	39,569	$ 38,152
Fair Value, Inputs, Level 1 [Member]
Total	39,569	22,087
Fair Value, Inputs, Level 2 [Member]
Total	0	16,065
Fair Value, Inputs, Level 3 [Member]
Total	0	0
Money Market Funds [Member]
Money market funds, included in cash equivalents	27,653	17,618
Money Market Funds [Member] \| Fair Value, Inputs, Level 1 [Member]
Money market funds, included in cash equivalents	27,653	17,618
Money Market Funds [Member] \| Fair Value, Inputs, Level 2 [Member]
Money market funds, included in cash equivalents	0	0
Money Market Funds [Member] \| Fair Value, Inputs, Level 3 [Member]
Money market funds, included in cash equivalents	0	0
US Treasury Securities [Member]
Fair Value	11,916	3,573
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value	11,916	3,573
US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value	0	0
US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value	$ 0	0
Debt Security, Government, Non-US [Member]
Fair Value		896
Debt Security, Government, Non-US [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value		896
Debt Security, Government, Non-US [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value		0
Debt Security, Government, Non-US [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value		0
Asset-Backed Securities [Member]
Fair Value		499
Asset-Backed Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value		0
Asset-Backed Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value		499
Asset-Backed Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value		0
Corporate Bond Securities [Member]
Fair Value		15,566
Corporate Bond Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Fair Value		0
Corporate Bond Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Fair Value		15,566
Corporate Bond Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Fair Value		$ 0

Note 4 - Grant Income

9 Months Ended

Sep. 30, 2023

Government Assistance [Text Block]

4. 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 and other forms of fibrotic lung diseases. In June 2021, the Company was selected to receive a €14.2 million (approximately $17.0 million as of June 2021) grant from the Bavarian Ministry of Economic Affairs, Regional Development and Energy (the Bavarian Grant) supporting research and development for the program.

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 December 2023 (with submission for reimbursements allowed through February 2024). The timing of reimbursements 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 December 2023. In this case, the Company may also be required to refund some or all of the amounts received under the grant. The Company is required to communicate the amount of such proceeds to the Bavarian Ministry of Economic Affairs, Regional Development and Energy in each case with the request to draw down the funds. In addition, the Company is required to communicate if there is a change in control or other event that would impact the continuation of PRS-220 to the Bavarian project agency, in which case the Company may be required to refund some or all of amounts received under the grant.

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Operating activities:
Net loss	$ (19,959)	$ (25,175)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	2,102	2,195
Right-of-use asset (accretion) amortization	(98)	0
Stock-based compensation	2,898	3,453
Asset impairment	14,893	0
Realized investment (losses) gains	(53)	(299)
Other non-cash transactions	(129)	216
Changes in operating assets and liabilities	(33,804)	(27,389)
Net cash used in operating activities	(34,150)	(46,999)
Investing activities:
Purchases of property and equipment	(184)	(1,052)
Proceeds from maturity of investments	24,007	21,900
Purchases of investments	(15,270)	(43,191)
Net cash provided by (used in) investing activities	8,553	(22,343)
Financing activities:
Proceeds from exercise of stock options	0	95
Proceeds from employee stock purchase plan	52	104
Proceeds from issuance of common stock resulting from ATM sales, net of $0.7 million and $0.3 million in transaction costs, respectively	19,729	6,922
Net cash provided by financing activities	19,781	7,121
Effect of exchange rate change on cash and cash equivalents	75	(7,120)
Net decrease in cash and cash equivalents	(5,741)	(69,341)
Cash and cash equivalents at beginning of period	38,635	117,764
Cash and cash equivalents at end of period	32,894	48,423
Supplemental cash flow disclosures:
Net unrealized gain on investments	74	82
Property and equipment included in accounts payable	$ 0	$ 31

Note 10 - Leases (Tables)

9 Months Ended

Sep. 30, 2023

Lease, Cost [Table Text Block]

	*Three Months Ended September 30,*				*Nine Months Ended September 30,*
	*2023*		*2022*		*2023*		*2022*
Operating lease costs	$	280	$	314	$	862	$	943
Variable lease costs (1)		98		148		476		446
Total lease cost	$	378	$	462	$	1,338	$	1,389

	*As of September 30, 2023*
Weighted-average remaining lease term (years)		8.8
Weighted-average discount rate		10.5	%

Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]

	*Total*
2023	$	522
2024		2,087
2025		2,087
2026		2,087
2027		2,087
Thereafter		9,565
Total undiscounted lease payments		18,435
Less: present value adjustment		(6,142	)
Present value of lease liabilities	$	12,293

Note 1 - Corporate Information

9 Months Ended

Sep. 30, 2023

Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]

1. Corporate Information

Pieris Pharmaceuticals, Inc. was founded in May 2013, and acquired 100% interest in Pieris Pharmaceuticals GmbH (formerly Pieris AG, a German company that 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 has focused on the discovery and development of 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 is located in Hallbergmoos, Germany.

Pieris’ clinical pipeline includes an inhaled Anticalin protein targeting connective tissue growth factor to treat idiopathic pulmonary fibrosis, an immuno-oncology, or IO, bispecific targeting 4-1BB and PD-L1, which is being advanced by Servier, an IO bispecific targeting 4-1BB and CD228, which is being advanced by Seagen, and an IO bispecific targeting 4-1BB and GPC3, which is being advanced by Boston Pharmaceuticals. The Company’s core Anticalin technology and platform were developed in Germany, and the Company has partnership arrangements with several major multi-national pharmaceutical companies.

The Company has historically been 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, and reliance on third-party manufacturers, suppliers, and service providers. The Company has historically devoted substantially all of its financial resources and efforts to research and development and general and administrative expenses to support such research and development. Going forward and as explained in more detail below, the Company plans to continue to devote substantial time and resources into exploring strategic transactions that the Company's board of directors believes would maximize shareholder value.

Strategic Update and Reduction in Force

On July 18, 2023, the Company announced its intention to explore engaging in one or more strategic transactions, including mergers, reverse mergers, acquisitions, other business combinations or sales of assets, or other strategic transactions. This decision was primarily related to recent events that have impacted the Company’s inhaled respiratory franchise, including AstraZeneca's discontinuation of enrollment of the Phase 2a study for elarekibep. As part of this initiative, the Company engaged Stifel, Nicolaus & Company, Incorporated to serve as strategic advisor in its review of strategic transactions. The Company continues to explore various potential strategic alternatives, such as mergers, reverse mergers, acquisitions, other business combinations or sales of assets, as well as potential partnerships for its therapeutic programs, including cinrebafusp alfa (PRS-343).

Also on July 18, 2023, the Company’s board of directors approved a reduction in the Company’s workforce by approximately 70%. The Company incurred approximately $6.8 million of costs in connection with the reduction in workforce related to severance pay and other related termination benefits in the third quarter of 2023, inclusive of severance pay and related costs for currently retained employees estimated to be paid through the second quarter of 2024 as the service period to earn such benefits is considered complete.

Going Concern Uncertainties

As of September 30, 2023, cash, cash equivalents, and investments were $44.8 million. For the three months ended September 30, 2023 and 2022, the Company had net losses of $10.8 million and $9.7 million, respectively. The Company has incurred net losses since inception and had an accumulated deficit of $310.4 million as of September 30, 2023. Net losses and negative cash flows from operations 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 the foreseeable future.

As part of the Company's decision to explore strategic transactions, the Company implemented a plan to limit a substantial portion of its research, development and clinical projects, including stopping future investments in PRS-220 phase 2a readiness activities and research and development activities for PRS-400, opting out of co-development of PRS-344/S095012 in the U.S., and reducing discretionary expenditures and other fixed or variable personnel costs.

Further investments in these or other programs could be reevaluated in the future if the Company is successfully able to consummate strategic transactions or collaborations, licensing arrangements, or public or private equity financings. Furthermore, the Company expects to devote substantial time and resources to exploring strategic transactions that the board of directors believes will maximize stockholder value. Despite devoting significant efforts to identify and evaluate potential strategic transactions, there can be no assurance that this strategic review process will result in the Company pursuing any transaction or that any transaction, if pursued, will be completed on attractive terms or at all. The Company has not set a definitive timetable for completion of this strategic review process, and the board of directors has not approved a definitive course of action. Additionally, there can be no assurances that any particular course of action, business arrangement or transaction, or series of transactions, will be pursued, successfully consummated or lead to increased stockholder value. In addition, if the Company seeks to raise additional capital to fulfill its operating and capital requirements through public or private equity financings, utilization of its current “at the market offering” program, or ATM Program, strategic collaborations, licensing arrangements, government grants and/or the achievement of milestones under its collaborative agreements, there is no assurance that the Company would be successful in obtaining sufficient funding on terms acceptable to the Company to fund continuing operations, if at all, and the terms of any future financing may adversely affect the holdings or the rights of the Company’s existing stockholders. On the basis of the Company’s approved budget and actions within management’s control, the Company believes that its currently available funds will be sufficient to fund the Company’s remaining limited operations through at least the next 12 months from the issuance of this Quarterly Report on Form 10-Q. The Company’s belief with respect to its ability to fund operations is based on estimates that are subject to risks and uncertainties.

Note 6 - Assets Held for Sale, Property and Equipment - Summary of Assets Held for Sale (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Net Book Value	$ 2,098
Laboratory Furniture and Equipment [Member]
Net Book Value	1,887
Office Furniture and Equipment [Member]
Net Book Value	$ 211

Note 9 - Stockholders' Equity (Details Textual) - USD ($) $ / shares in Units, $ in Millions				1 Months Ended		9 Months Ended
	Jun. 21, 2023	Jun. 22, 2022	Jun. 25, 2021	Nov. 30, 2022	Aug. 31, 2021	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2023	Dec. 31, 2022	Dec. 31, 2020
Common Stock, Shares Authorized (in shares)						300,000,000			300,000,000
Common Stock, Shares, Issued (in shares)						98,851,927			74,519,103
Common Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.001			$ 0.001
Preferred Stock, Shares Authorized (in shares)						10,000,000			10,000,000
Preferred Stock, Shares Issued (in shares)						15,617			15,617
Preferred Stock, Par or Stated Value Per Share (in dollars per share)						$ 0.001			$ 0.001
Preferred Stock, Shares Outstanding, Ending Balance (in shares)						15,617			15,617
Common Stock, Shares, Outstanding (in shares)								98,851,927	74,519,103
Jefferies L L C [Member] \| At the Market Offering [Member]
Sale of Stock, Authorized Amount				$ 75.0	$ 50.0
Stock Issued During Period, Shares, New Issues (in shares)						24,300,000	2,100,000
Stock Issued During Period, Value, Issued for Services						$ 20.3	$ 7.2
Shares Issued, Price Per Share (in dollars per share)						$ 0.84	$ 3.46
Employee Director And Consultant Equity Incentive Plan2020 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)										3,500,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)										1,579,678
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	6,000,000	3,000,000	2,250,000
The 2023 Employee Stock Purchase Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)						750,000
Series A Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)						85			85
Preferred Stock, Shares Outstanding, Ending Balance (in shares)						85			85
Series B Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)						4,026			4,026
Preferred Stock, Shares Outstanding, Ending Balance (in shares)						4,026			4,026
Series C Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)						3,506			3,506
Preferred Stock, Shares Outstanding, Ending Balance (in shares)						3,506			3,506
Series D Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)						3,000			3,000
Preferred Stock, Shares Outstanding, Ending Balance (in shares)						3,000			3,000
Series E Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)						5,000			5,000
Preferred Stock, Shares Outstanding, Ending Balance (in shares)						5,000			5,000

Note 9 - Stockholders' Equity

9 Months Ended

Sep. 30, 2023

Equity [Text Block]

9. Stockholders’ Equity

The Company had 300,000,000 shares authorized and 98,851,927 and 74,519,103 shares of common stock issued and outstanding as of September 30, 2023 and December 31, 2022, 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 September 30, 2023 and December 31, 2022. Preferred stock has a par value of $0.001 per share, and consists of the following:

•

Series A Convertible, 85 shares issued and outstanding at September 30, 2023 and December 31, 2022, respectively.

•

Series B Convertible, 4,026 shares issued and outstanding at September 30, 2023 and December 31, 2022, respectively.

•

Series C Convertible, 3,506 shares issued and outstanding at September 30, 2023 and December 31, 2022, respectively.

•

Series D Convertible, 3,000 shares issued and outstanding at September 30, 2023 and December 31, 2022, respectively.

•

Series E Convertible, 5,000 shares issued and outstanding at September 30, 2023 and December 31, 2022, respectively.

2020 Employee, Director and Consultant Equity Incentive Plan

At the 2020 Annual Meeting of Stockholders, the Company's stockholders approved the 2020 Employee, Director and Consultant Equity Incentive Plan, or the 2020 Plan. The 2020 Plan permits 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. There were approximately 1,579,678 shares remaining and available for grant under the 2019 Plan that terminated upon original approval of the 2020 Plan.

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. At the 2022 Annual Meeting of Stockholders held on June 22, 2022, the Company’s stockholders approved a second amendment to the 2020 Plan to add 3,000,000 shares of common stock for issuance under the 2020 Plan. At the 2023 Annual Meeting of Stockholders held on June 21, 2023, the Company’s stockholders approved a third amendment to the 2020 Plan to add 6,000,000 shares of common stock for issuance under the 2020 Plan.

2023 Employee Stock Purchase Plan

At the 2023 Annual Meeting of Stockholders, the Company’s stockholders approved the 2023 Employee Stock Purchase Plan, or the 2023 ESPP. The 2023 ESPP provides eligible employees with the opportunity to purchase shares of the Company's common stock at a discount, on a tax-favored basis, through regular payroll deductions in compliance with federal tax regulations. The Company has reserved 750,000 shares of common stock for issuance under the 2023 ESPP.

Open Market Sales Agreements

In August 2021, the Company established an at-the-market program, or ATM Program, under 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 amount of gross sales proceeds of $50.0 million. The 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. In November 2022, the sales agreement was amended to provide for an increase in the aggregate offering amount, such that under the ATM Program, as amended, the Company may offer and sell shares of its common stock, from time to time, up to an aggregate amount of gross sales proceeds of $75.0 million.

For the nine months ended September 30, 2023, the Company sold 24.3 million shares for gross proceeds of $20.3 million under the ATM program at an average stock price of $0.84 per share. For the nine months ended September 30, 2022, the Company sold 2.1 million shares for gross proceeds of $7.2 million under the ATM Program at an average stock price of $3.46 per share.

The entire disclosure for equity.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Note 3 - Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Total revenue	$ 19,520	$ 5,370	$ 41,511	$ 20,056
Seattle Genetics Inc. [Member]
Total revenue	9,179	155	14,088	3,074
Astra Zeneca A B [Member]
Total revenue	3,909	4,404	8,399	9,026
Les Laboratoires Servier And Institut De Recherches Internationales Servier [Member]
Total revenue	3,951	258	3,846	5,223
Genentech [Member]
Total revenue	0	553	12,697	2,733
Boston Pharmaceuticals [Member]
Total revenue	$ 2,481	$ 0	$ 2,481	$ 0

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).

Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) (Parentheticals) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
At the Market Offering [Member]
Stock issuance costs	$ 0.7	$ 0.3

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current assets:
Cash and cash equivalents	$ 32,894	$ 38,635
Short term investments	11,916	20,534
Accounts receivable	1,045	5,810
Assets held for sale, property and equipment	2,098	0
Operating lease right-of-use assets, current	1,984	0
Prepaid expenses and other current assets	9,152	8,445
Total current assets	59,089	73,424
Property and equipment, net	0	16,992
Operating lease right-of-use assets, non-current	0	3,705
Other non-current assets	287	1,369
Total assets	59,376	95,490
Current liabilities:
Accounts payable	2,816	4,154
Operating lease liabilities, current	12,292	859
Accrued expenses and other current liabilities	12,764	10,746
Deferred revenues, current portion	994	20,824
Total current liabilities	28,866	36,583
Deferred revenue, net of current portion	0	18,734
Operating lease liabilities, non-current	0	12,244
Total liabilities	28,866	67,561
Stockholders’ equity:
Preferred stock	0	0
Common stock	99	74
Additional paid-in capital	341,130	318,530
Accumulated other comprehensive loss	(339)	(254)
Accumulated deficit	(310,380)	(290,421)
Total stockholders’ equity	30,510	27,929
Total liabilities and stockholders’ equity	$ 59,376	$ 95,490

Note 6 - Assets Held for Sale, Property and Equipment (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Asset Impairment Charges	$ 14,893	$ 0	$ 14,893	$ 0
Long-Lived Assets Held-for-Sale, Net Book Value	2,098		$ 2,098
Office and Laboratory Space [Member] \| Hallbergmoos Germany [Member]
Operating Lease, Impairment Loss	$ 1,800

Note 2 - Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2023

Significant Accounting Policies [Text Block]

2. Summary of Significant Accounting Policies

The Company’s significant accounting policies are described in Note 2—Summary of Significant Accounting Policies, in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022. There have been no material additions to the significant accounting policies for the nine months ended September 30, 2023.

Unaudited Interim Financial Information

The accompanying unaudited condensed consolidated financial statements included herein have been prepared by the Company in accordance with accounting principles generally accepted in the United States, or U.S. GAAP, for interim financial information and pursuant to the rules and regulations of the SEC. Accordingly, certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to such rules and regulations. In the opinion of management, all adjustments, consisting of normal recurring adjustments, and disclosures considered necessary for a fair presentation of interim period results have been included. Interim results for the three and nine months ended September 30, 2023 are not necessarily indicative of results that may be expected for the year ending December 31, 2023. For further information, refer to the financial statements and footnotes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2022, which was filed with the SEC on March 31, 2023.

Basis of Presentation and Use of Estimates

The accompanying condensed consolidated financial statements of Pieris Pharmaceuticals, Inc. and its wholly-owned subsidiaries were prepared in accordance with U.S. GAAP. The condensed 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; fair value of assets held for sale; 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.

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 Financial Accounting Standards Board, or FASB, Accounting Standards Codification, or 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 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.

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 minimize 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, 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 (see Note 5).

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.

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. 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

If the criteria in ASC 360 Property, Plant and Equipment are met, a long-lived asset is classified as held for sale. The long-lived asset is reported at the lower of its carrying value or fair value less cost to sell beginning in the period the held for sale criteria are met. The carrying amount of the asset will be adjusted each reporting period for subsequent changes in fair value less cost to sell. A loss is recognized for any subsequent write-down to fair value less cost to sell. A gain is recognized for any subsequent increase in fair value less cost to sell, but not in excess of the cumulative loss previously recognized. Once classified as held for sale, depreciation and amortization are no longer recorded for any long-lived assets included in the disposal group.

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 assets are considered to be located in Germany, the Company records all consolidated revenue in its subsidiary, Pieris Pharmaceuticals GmbH.

Collaborative Arrangements

The Company considers the nature and contractual terms of an arrangement and assesses 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 condensed consolidated statement of operations.

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. The Company 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.

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 condensed 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) in the condensed consolidated statements of operations.

Leases

In accordance with ASU No. 2016-2, Leases (Topic 842), or ASC 842, and for each of the Company’s leases, the following is recognized: (i) a lease liability, which is a lessee’s 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.

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.

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 noncancellable 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.

Recent Accounting Pronouncements 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 adopted the standard as of January 1, 2023 and concluded the effect to the unaudited condensed consolidated financial statements was immaterial.

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 condensed consolidated financial statements as a result of future adoption.

Note 5 - Cash, Cash Equivalents and Investments

9 Months Ended

Sep. 30, 2023

Cash, Cash Equivalents, and Marketable Securities [Text Block]

5. Cash, cash equivalents and investments

As of September 30, 2023 and December 31, 2022, cash, cash equivalents and investments comprised funds in depository, money market accounts, U.S. and foreign treasury securities, asset-backed securities and corporate bonds. The following table presents the cash equivalents and investments carried at fair value in accordance with the hierarchy defined in Note 2 at September 30, 2023 and December 31, 2022.

	*Total*		*Quoted prices in active markets (Level 1)*		*Significant other observable inputs (Level 2)*		*Significant unobservable inputs (Level 3)*
September 30, 2023
Money market funds, included in cash equivalents	$	27,653	$	27,653	$	—	$	—
Investments - US treasuries		11,916		11,916		—		—
Total	$	39,569	$	39,569	$	—	$	—

	*Total*		*Quoted prices in active markets (Level 1)*		*Significant other observable inputs (Level 2)*		*Significant unobservable inputs (Level 3)*
December 31, 2022
Money market funds, included in cash equivalents	$	17,618	$	17,618	$	—	$	—
Investments - US treasuries		3,573		3,573		—		—
Investments - Foreign treasuries		896		896		—		—
Investments - Asset-backed securities		499		—		499		—
Investments - Corporate bonds		15,566		—		15,566		—
Total	$	38,152	$	22,087	$	16,065	$	—

Cash equivalents and marketable securities have been initially valued at the transaction price and subsequently valued, at the end of each reporting period, utilizing third party pricing services or other market observable data. The pricing services utilize industry standard valuation models, including both income and market-based approaches and observable market inputs to determine value. The Company validates the prices provided by its third-party pricing services by reviewing their pricing methods and obtaining market values from other pricing sources, as needed. After completing its validation procedures, the Company did not adjust any fair value measurements provided by the pricing services as of September 30, 2023.

Investments at September 30, 2023 consisted of the following (in thousands):

	*Contractual maturity*
	*(in days)*		*Amortized Cost*		*Unrealized gains*		*Unrealized losses*		*Fair Value*
Investments
US treasuries		3-101	$	11,915	$	1	$	—	$	11,916
Total			$	11,915	$	1	$	—	$	11,916

The Company recorded no realized gains or losses and $0.1 million in realized losses from the maturity of available-for-sale securities during the three and nine months ended September 30, 2023, respectively, and recorded $0.2 million and $0.3 million in realized gains from the maturity of available-for-sale securities during the three and nine months ended September 30, 2022, respectively.

As of September 30, 2023, there were no investments with a fair value that was significantly lower than the amortized cost basis or any investments that had been in an unrealized loss position for a significant period.

Note 4 - Grant Income (Details Textual) - Jun. 30, 2021 € in Millions, $ in Millions	USD ($)	EUR (€)
Grants Receivable	$ 17	€ 14.2

Note 10 - Leases - Operating Lease Costs (Details) - USD ($)
$ in Thousands

3 Months Ended

9 Months Ended

Sep. 30, 2023

Sep. 30, 2022

Sep. 30, 2023

Sep. 30, 2022

Operating lease costs

$ 280

$ 314

$ 862

$ 943

Variable lease costs (1)

^[1]

148

476

446

Total lease cost

$ 378

$ 462

$ 1,338

$ 1,389

Weighted-average remaining lease term (years) (Year)

8 years 9 months 18 days

Weighted-average discount rate

10.50%

[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.

Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2023

Accounting Policies [Abstract]

Basis of Accounting, Policy [Policy Text Block]

Unaudited Interim Financial Information

Use of Estimates, Policy [Policy Text Block]

Basis of Presentation and Use of Estimates

Cash and Cash Equivalents, Policy [Policy Text Block]

Cash, Cash Equivalents and Investments

Concentration Risk, Credit Risk, Policy [Policy Text Block]

Concentration of Credit Risk and Off-Balance Sheet Risk

Fair Value Measurement, Policy [Policy Text Block]

Fair Value Measurement

•

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.

Financial instruments measured at fair value on a recurring basis include cash equivalents and investments (see Note 5).

Property, Plant and Equipment, Policy [Policy Text Block]

Property and Equipment

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

Revenue [Policy Text Block]

Revenue Recognition

Collaborative Arrangements

Revenue from Contracts with Customers

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

Milestones and Royalties

Contract Balances

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

Government Assistance [Policy Text Block]

Government Grants

Lessee, Leases [Policy Text Block]

Leases

New Accounting Pronouncements, Policy [Policy Text Block]

Recent Accounting Pronouncements Adopted

Note 5 - Cash, Cash Equivalents and Investments (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Debt Securities, Available-for-Sale, Realized Gain (Loss)	$ 0	$ 200	$ (100)	$ 300

Note 3 - Revenue (Details Textual) $ / shares in Units, $ in Thousands					1 Months Ended		3 Months Ended				6 Months Ended	9 Months Ended		12 Months Ended
	May 19, 2021 USD ($)	Apr. 24, 2021 USD ($)	Mar. 24, 2021 USD ($) $ / shares shares	Feb. 08, 2018 USD ($)	Sep. 30, 2023 USD ($)	Jan. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2017	Jan. 01, 2019 USD ($)	May 02, 2017 USD ($)
Contract with Customer, Liability, Revenue Recognized							$ 17,100					$ 38,700
Contract with Customer, Liability, Current					$ 994		994				$ 994	994		$ 20,824
Increase (Decrease) in Contract with Customer, Liability							0					0
Amendment of the Second Seagen Amendment [Member]
Revenue from Contract with Customer, Excluding Assessed Tax					9,000
Genentech [Member]
Number Of Initial Research Programs	2
Contract with Customer, Liability, Revenue Recognized								$ 12,500
Revenue from Contract with Customer, Collaboration Fee On Additional Program	$ 10,000
Number Of Optional Additional Research Programs	2
Seattle Genetics Inc. [Member]
Number of Performance Obligations				3
Amended Collaboration Agreement, Resale of Stock, Period (Day)			60 days
Seattle Genetics Inc. [Member] \| Private Placement [Member]
Contract with Customer, Liability, Total			$ 3,300
Sale of Stock, Number of Shares Issued in Transaction (in shares) \| shares			3,706,174
Sale of Stock, Consideration Received on Transaction			$ 13,000
Sale of Stock, Price Per Share (in dollars per share) \| $ / shares			$ 3.51
Sale of Stock, Fair Value, Price Per Share (in dollars per share) \| $ / shares			$ 2.61
Seattle Genetics Inc. [Member] \| License and Collaboration Agreement [Member]
Number of Research Programs			3	3
Revenue from Contract with Customer, Period After Effective Date Agreements May Be Terminated (Month)				12 months
Revenue from Contract with Customer, Agreement Termination Advance Notice Period (Day)				90 days
Revenue from Contract with Customer, Agreement Termination Advance Notice Period If Marketing Approval Obtained (Day)				180 days
Revenue from Contract with Customer, Agreement Termination Notice Period Upon Material Breach (Day)				90 days
Revenue from Contract with Customer, Agreement Termination, Additional Notice Period Upon Material Breach (Day)				90 days
Number Of Licenses				3
Number Of Swap Options				2
Number of Performance Obligations				6
Revenue, Remaining Performance Obligation, Amount					1,000		1,000				1,000	1,000
Seattle Genetics Inc. [Member] \| Other Arrangement [Member]
Number of Research Programs				2
Seattle Genetics Inc. [Member] \| Up-front Payment Arrangement [Member]
Contract with Customer, Liability, Total				$ 1,200,000
Research and Development Arrangement, Contract to Perform for Others, Compensation Earned				$ 4,900
Seattle Genetics Inc. [Member] \| Platform Technology License [Member]
Number of Performance Obligations				3
Number of Target Programs				3
Seattle Genetics Inc. [Member] \| Antibody Target Swap [Member]
Number of Performance Obligations				2
Seattle Genetics Inc. [Member] \| Governance Committee Participation [Member]
Number of Performance Obligations				1
Seattle Genetics Inc. [Member] \| Collaborative Arrangement [Member]
Revenue from Contract with Customer, Excluding Assessed Tax						$ 5,000								5,000
Contract with Customer, Liability, Current					1,000		1,000				1,000	1,000
Astra Zeneca A B [Member]
Capitalized Contract Cost, Net, Total					100		100				100	100
Capitalized Contract Cost, Amortization									$ 200			300	$ 300
Astra Zeneca A B [Member] \| Accounting Standards Update 2014-09 [Member]
Capitalized Contract Cost, Net, Total																	$ 1,600
Capitalized Contract Cost, Gross																$ 1,100
Astra Zeneca A B [Member] \| License and Collaboration Agreement [Member]
Contract with Customer, Liability, Revenue Recognized											4,000			$ 9,700
Contract with Customer, Liability, Current					3,500		3,500				3,500	3,500
Astra Zeneca A B [Member] \| License and Collaboration Agreement [Member] \| Maximum [Member]
Number of Collaboration Products																	4
Astra Zeneca A B [Member] \| License and Collaboration Agreement [Member] \| Minimum [Member]
Number of Collaboration Products																	2
Les Laboratoires Servier And Institut De Recherches Internationales Servier [Member]
Contract with Customer, Liability, Revenue Recognized										$ 4,900
Number of Programs															4
Number of Novel Proteins															1
Les Laboratoires Servier And Institut De Recherches Internationales Servier [Member] \| License and Collaboration Agreement [Member]
Contract with Customer, Liability, Current					$ 4,700		$ 4,700				$ 4,700	$ 4,700
Number of Programs															5
License [Member] \| Genentech [Member]
Contract with Customer, Liability, Total	$ 20,000
License [Member] \| B P Assets X I I Inc [Member] \| Exclusive Product License Agreement [Member]
Contract with Customer, Liability, Total		$ 10,000
Revenue from Contract with Customer, Contribution Towards Manufacturing Activities		$ 4,000
License [Member] \| Seattle Genetics Inc. [Member] \| Up-front Payment Arrangement [Member]
Revenue from Contract with Customer, Excluding Assessed Tax				$ 30,000

Note 5 - Cash, Cash Equivalents and Investments - Investments (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Dec. 31, 2022
Amortized cost	$ 11,915
Unrealized gains	1
Unrealized losses	0
Fair Value	11,916
US Treasury Securities [Member]
Amortized cost	11,915
Unrealized gains	1
Unrealized losses	0
Fair Value	$ 11,916	$ 3,573
US Treasury Securities [Member] \| Minimum [Member]
Contractual Maturity Period (Day)	3 days
US Treasury Securities [Member] \| Maximum [Member]
Contractual Maturity Period (Day)	101 days

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenue
Customer revenue	$ 15,569	$ 5,112	$ 37,665	$ 19,760
Collaboration revenue	3,951	258	3,846	296
Total revenue	19,520	5,370	41,511	20,056
Operating expenses
Research and development	9,595	13,589	37,347	39,602
General and administrative	6,839	3,949	14,526	12,409
Asset impairment	14,893	0	14,893	0
Total operating expenses	31,327	17,538	66,766	52,011
Loss from operations	(11,807)	(12,168)	(25,255)	(31,955)
Other income (expense)
Interest income	549	241	1,396	370
Grant income	0	1,468	3,612	4,782
Other income (loss)	506	723	288	1,628
Net loss	(10,752)	(9,736)	(19,959)	(25,175)
Other comprehensive income loss:
Foreign currency translation	(204)	(31)	(159)	(387)
Unrealized gain on available-for-sale securities	2	(70)	74	82
Comprehensive loss	$ (10,954)	$ (9,837)	$ (20,044)	$ (25,480)
Net loss per share
Basic and diluted (in dollars per share)	$ (0.11)	$ (0.13)	$ (0.23)	$ (0.34)
Weighted average number of common shares outstanding
Basic and diluted (in shares)	98,852	74,397	87,093	74,080

Note 1 - Corporate Information (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Jul. 18, 2023	Dec. 31, 2022	May 31, 2013
Reduction in Workforce, Percentage					70.00%
Reduction in Workforce, Cost	$ 6,800		$ 6,800
Cash, Cash Equivalents, and Short-Term Investments	44,800		44,800
Net Income (Loss) Attributable to Parent	(10,752)	$ (9,736)	(19,959)	$ (25,175)
Retained Earnings (Accumulated Deficit)	$ (310,380)		$ (310,380)			$ (290,421)
Pieris Pharmaceuticals GmbH [Member]
Business Acquisition, Percentage of Voting Interests Acquired							100.00%

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

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Amount of accumulated undistributed earnings (deficit).

+ References + Details

Note 6 - Assets Held for Sale, Property and Equipment - Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Property and equipment, cost		$ 26,639
Accumulated depreciation		(9,647)
Property and equipment, net	$ 0	16,992
Laboratory Equipment [Member]
Property and equipment, cost		11,970
Office Equipment [Member]
Property and equipment, cost		1,861
Computer Equipment [Member]
Property and equipment, cost		364
Leasehold Improvements [Member]
Property and equipment, cost		$ 12,444

Note 5 - Cash, Cash Equivalents and Investments (Tables)

9 Months Ended

Sep. 30, 2023

Cash, Cash Equivalents and Investments [Table Text Block]

	*Total*		*Quoted prices in active markets (Level 1)*		*Significant other observable inputs (Level 2)*		*Significant unobservable inputs (Level 3)*
September 30, 2023
Money market funds, included in cash equivalents	$	27,653	$	27,653	$	—	$	—
Investments - US treasuries		11,916		11,916		—		—
Total	$	39,569	$	39,569	$	—	$	—

	*Total*		*Quoted prices in active markets (Level 1)*		*Significant other observable inputs (Level 2)*		*Significant unobservable inputs (Level 3)*
December 31, 2022
Money market funds, included in cash equivalents	$	17,618	$	17,618	$	—	$	—
Investments - US treasuries		3,573		3,573		—		—
Investments - Foreign treasuries		896		896		—		—
Investments - Asset-backed securities		499		—		499		—
Investments - Corporate bonds		15,566		—		15,566		—
Total	$	38,152	$	22,087	$	16,065	$	—

Debt Securities, Available-for-Sale [Table Text Block]

	*Contractual maturity*
	*(in days)*		*Amortized Cost*		*Unrealized gains*		*Unrealized losses*		*Fair Value*
Investments
US treasuries		3-101	$	11,915	$	1	$	—	$	11,916
Total			$	11,915	$	1	$	—	$	11,916

Tabular disclosure of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-9

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (aaa)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 8: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-2

Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 10: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Reference 12: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481800/320-10-50-3

Note 10 - Leases - Maturities of Operating Lease Liabilities (Details) $ in Thousands	Sep. 30, 2023 USD ($)
2023	$ 522
2024	2,087
2025	2,087
2026	2,087
2027	2,087
Thereafter	9,565
Total undiscounted lease payments	18,435
Less: present value adjustment	(6,142)
Present value of lease liabilities	$ 12,293

Note 2 - Summary of Significant Accounting Policies - Schedule of Property, Plant and Equipment, Useful Lives (Details)	Sep. 30, 2023
Laboratory Equipment [Member] \| Minimum [Member]
Property and equipment, useful life (Year)	8 years
Laboratory Equipment [Member] \| Maximum [Member]
Property and equipment, useful life (Year)	14 years
Office Equipment [Member] \| Minimum [Member]
Property and equipment, useful life (Year)	5 years
Office Equipment [Member] \| Maximum [Member]
Property and equipment, useful life (Year)	13 years
Computer Equipment [Member] \| Minimum [Member]
Property and equipment, useful life (Year)	3 years
Computer Equipment [Member] \| Maximum [Member]
Property and equipment, useful life (Year)	7 years

Note 8 - Net Income (Loss) Per Share

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Text Block]

8. Net Income (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.

As of September 30, 2023 and 2022, and as calculated using the treasury stock method, approximately 41.0 million and 38.8 million of weighted average shares, respectively, were excluded from the calculation of diluted weighted average shares outstanding as their effect was antidilutive.

Note 3 - Revenue (Tables)

9 Months Ended

Sep. 30, 2023

Disaggregation of Revenue [Table Text Block]

	*Three Months Ended September 30,*				*Nine Months Ended September 30,*
	*2023*		*2022*		*2023*		*2022*
Seagen	$	9,179	$	155	$	14,088	$	3,074
AstraZeneca		3,909		4,404		8,399		9,026
Servier		3,951		258		3,846		5,223
Genentech		—		553		12,697		2,733
Boston Pharmaceuticals		2,481		—		2,481		—
Total Revenue	$	19,520	$	5,370	$	41,511	$	20,056

Revenue From Contract With Customer, Milestone Payments [Table Text Block]

	*Research, Development, Regulatory & Commercial Milestones*		*Sales Milestones*
Seagen	$	759	$	450
Servier		103		95
Boston Pharmaceuticals		85		265
Total potential milestone payments	$	947	$	810

Note 3 - Revenue

9 Months Ended

Sep. 30, 2023

Revenue from Contract with Customer [Text Block]

3. Revenue

General

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

The Company recognized revenue from the following strategic partnerships and other license agreements (in thousands):

	*Three Months Ended September 30,*				*Nine Months Ended September 30,*
	*2023*		*2022*		*2023*		*2022*
Seagen	$	9,179	$	155	$	14,088	$	3,074
AstraZeneca		3,909		4,404		8,399		9,026
Servier		3,951		258		3,846		5,223
Genentech		—		553		12,697		2,733
Boston Pharmaceuticals		2,481		—		2,481		—
Total Revenue	$	19,520	$	5,370	$	41,511	$	20,056

As of September 30, 2023, under the Company’s existing strategic partnerships and other license agreements, the Company could receive the following potential milestone payments (in millions):

	*Research, Development, Regulatory & Commercial Milestones*		*Sales Milestones*
Seagen	$	759	$	450
Servier		103		95
Boston Pharmaceuticals		85		265
Total potential milestone payments	$	947	$	810

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.

Under the terms of the Genentech Agreement, the Company was responsible for discovery and preclinical development of two initial programs. In April and May 2023, Genentech and the Company decided to discontinue the discovery-stage programs in ophthalmology and respiratory, respectively, for scientific reasons. Pursuant to this decision, the material right performance obligations related to the target swaps for these programs also expired. Based on these decisions, there are no more active performance obligations remaining under the collaboration and the Company recognized all remaining revenue, or $12.5 million, under the collaboration in the three months ended June 30, 2023.

Genentech still has an option to select additional programs with the payment of a $10 million fee per additional program. If Genentech exercises its option to start additional programs, the Company would be eligible to receive additional milestone payments, as well as tiered royalty payments on net sales, subject to certain standard reductions and offsets. Genentech’s options to nominate two additional collaboration targets of their choosing is subject to the legal availability of the target to be researched.

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/BOS-342, a 4-1BB/GPC3 preclinical immuno-oncology Mabcalin^TM (antibody-Anticalin fusion) protein.

Under the terms of the BP Agreement, Boston Pharmaceuticals exclusively licensed worldwide rights to PRS-342/BOS-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/BOS-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 also contributed $4.0 million toward manufacturing activities.

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/BOS-342. In the fourth quarter of 2021, the Company transferred all deliverables to Boston Pharmaceuticals related to the one performance obligation under the collaboration. Therefore, the Company recognized the full transaction price as revenue in 2021 and there are no remaining obligations. In August 2023, the first patient was dosed in the Boston Pharmaceuticals sponsored Phase 1/2 study of PRS-342/BOS-342 in heptacellular carcinoma (HCC), for which the Company received a milestone payment.

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. (formerly Seattle Genetics, Inc.), or Seagen, pursuant to which the parties agreed to develop multiple targeted bispecific IO treatments for solid tumors and blood cancers.

Under the terms of the Seagen Agreements, the companies agreed to pursue multiple antibody-Anticalin 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 agreed to 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 the Company 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 up to $1.2 billion in total 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, the Company would be entitled to additional fees, and potential milestone payments and royalties.

The term of each of the Seagen Agreements ends upon the expiration of all of Seagen’s payment obligations under each such 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 predefined preclinical stage, the Company will have full rights to continue such program. If any program is terminated by Seagen prior to such predefined preclinical 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 were 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 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 $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 on a straight-line basis over the anticipated research term for all research programs. As of September 30, 2023, there was $1.0 million of aggregate transaction price allocated to remaining performance obligations.

On March 24, 2021, the Company announced that Seagen made a strategic equity investment in the Company, 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. Enrollment into the phase 2 study was ceased in August 2022 as part of a strategic pipeline prioritization, and the Combination Study Agreement was terminated. The companies have also entered into an Amended and Restated License and Collaboration Agreement, or the Second Seagen Amendment, in which their existing IO collaboration agreement has been amended relating to joint development and commercial rights for the second program in the alliance. In connection with the agreements described above, the Company and Seagen also entered into a subscription agreement, or the Seagen Subscription Agreement.

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 of one of the three programs 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 Seagen Subscription Agreement, 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. 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 other 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. With the exception of the previously discussed achieved milestone, 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.

     In
     January 2023, the Company achieved a milestone for the
    first program in the Seagen collaboration for
    $5.0 million. The Company evaluated the recognition of the milestone under ASC
    606 and concluded that the constraints on the milestone
    no longer existed as of
     December 31, 2022 and therefore recorded the full
    $5.0 million as revenue for the year ended
     December 31, 2022.
   

     In
     September 2023, Seagen and the Company entered into an amendment of the Second Seagen Amendment that provides Seagen with collaboration product licenses and
    no changes to the amounts achievable under the collaboration agreement.
    
      The effect of the
      September 30, 2023 amendment was to transfer responsibility for substantially all activities previously performed by the Company to Seagen.  Accordingly, the Company recognized revenue of approximately
     $9.0 million for the delivery on its performance obligations related to the
     two programs.
    

As of September 30, 2023, there was $1.0 million of current deferred revenue 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.

In addition to elarekibep (formerly known as PRS-060/AZD1402), or the AstraZeneca Lead Product, the Company and AstraZeneca agreed to collaborate, under the original terms of the AstraZeneca Collaboration Agreement, 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. As of June 30, 2023, the AstraZeneca Lead Product and three of the four AstraZeneca Collaboration Products had been discontinued. The first two discovery-stage programs were previously discontinued in 2022, which led to approximately $9.7 million in revenue recognized due to these discontinuations. Elarekibep and the third discovery-stage program were discontinued in the second quarter of 2023. There was no effect to revenue as a result of the discontinuation of elarekibep, while the discontinuation of the third discovery program led to recognition of $4.0 million of revenue in the quarter ended June 30, 2023.

On July 17, 2023, AstraZeneca notified the Company of its intention to terminate the AstraZeneca Collaboration Agreement and the AstraZeneca Platform License, effective October 15, 2023. AstraZeneca’s decision to terminate the AstraZeneca Agreements was based on non-clinical safety findings in a 13-week toxicology study of elarekibep in non-human primates previously disclosed by the Company. As a result of this, the remaining amount of current deferred revenue, or $3.5 million, as of September 30, 2023 was recognized in revenue in the third quarter of 2023. With the termination of the AstraZeneca Agreements, there are no more active programs or performance obligations related to the collaboration. Following the termination date, the Company will be free to choose to further develop all assets that were the subject of the AstraZeneca Agreements; the Company will evaluate the programs and its rights under the AstraZeneca Agreements and determine its strategic options after its review.

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. In accordance with the termination of the AstraZeneca Agreements and recognition of remaining revenue, the Company also amortized the remaining deferred transactions costs to obtain the contract, or $0.1 million, during the three months ended September 30, 2023. Amortization during the nine months ended September 30, 2023 was $0.3 million. Amortization during the three and nine months ended September 30, 2022 was $0.2 million and $0.3 million, respectively.

Servier

In 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. The intention of the collaboration and defined programs was to 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.

In the first quarter of 2022, the Company satisfied the performance obligation related to the material right for PRS-352/S095025, which led to point-in-time recognition of revenue for $4.9 million of revenue previously deferred. In the fourth quarter of 2022, Servier discontinued development of PRS-352/S095025 based upon a strategic portfolio review. Since inception, four of the five initially committed programs have been discontinued by Servier. The Company does not presently intend to continue development of the four discontinued programs but retains full rights to advance the development and commercialization of those products on a world-wide basis in the future.

In July 2023, the Company notified Servier of its decision to opt out co-development and commercialization of PRS- 344/S095012, a 4- 1BB/PD- L1 bispecific Mabcalin protein, in the U.S. Servier retains exclusive, even as to the Company, worldwide rights to the program, including the right to continue to advance development and potential commercialization of PRS- 344/S095012 in the U.S. As a result of the Company's decision to opt out of co-development, the Company will be entitled to increased royalty rates and potential royalties and milestones, if any, for PRS- 344/S095012 under the terms of the Servier Agreement. With the decision to opt out of co-development of PRS- 344/S095012, the Company recognized the remaining revenue under the collaboration, or $4.7 million, in the quarter ended September 30, 2023 and there are no more active co-development programs under the collaboration.

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 no additions to deferred revenue during the three and nine months ended September 30, 2023. Reductions to deferred revenue were $17.1 million and $38.7 million for the three and nine months ended September 30, 2023, respectively.

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-9

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Paragraph 10
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Paragraph 15
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 12
-Subparagraph (a)
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (c)
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-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-12

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//606/tableOfContent

Note 7 - Accrued Expenses - Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Compensation expense	$ 8,735	$ 3,015
Research and development fees	1,971	5,758
Accrued accounts payable	1,348	1,245
Other current liabilities	575	483
Accrued license obligations	135	245
Total	$ 12,764	$ 10,746

Document And Entity Information - shares	9 Months Ended
Document And Entity Information - shares	Sep. 30, 2023	Nov. 09, 2023
Document Information [Line Items]
Entity Central Index Key	0001583648
Entity Registrant Name	PIERIS PHARMACEUTICALS, INC.
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2023
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2023
Document Transition Report	false
Entity File Number	001-37471
Entity Incorporation, State or Country Code	NV
Entity Tax Identification Number	30-0784346
Entity Address, Address Line One	225 Franklin Street, 26th Floor
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02110
City Area Code	857
Local Phone Number	246-8998
Title of 12(b) Security	Common Stock, $0.001 par value per share
Trading Symbol	PIRS
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		98,851,927

Note 3 - Revenue - Potential Milestone Payments Received (Details) - Collaborative Arrangement [Member] $ in Millions	Sep. 30, 2023 USD ($)
Research And Development Milestone Payments [Member]
milestone	$ 947
Research And Development Milestone Payments [Member] \| Seattle Genetics Inc. [Member]
milestone	759
Research And Development Milestone Payments [Member] \| Servier Developed Collaboration Products [Member]
milestone	103
Research And Development Milestone Payments [Member] \| Boston Pharmaceuticals [Member]
milestone	85
Sales Milestone Payments [Member]
milestone	810
Sales Milestone Payments [Member] \| Seattle Genetics Inc. [Member]
milestone	450
Sales Milestone Payments [Member] \| Servier Developed Collaboration Products [Member]
milestone	95
Sales Milestone Payments [Member] \| Boston Pharmaceuticals [Member]
milestone	$ 265

Note 8 - Net Income (Loss) Per Share (Details Textual) - shares shares in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	41.0	38.8

Note 2 - Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2023

Property, Plant and Equipment, Estimated Useful Life [Table Text Block]

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

Note 7 - Accrued Expenses (Tables)

9 Months Ended

Sep. 30, 2023