0001437749-24-017037 | 10-Q | XBRL Viewer | Pieris Pharmaceuticals INC

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 (option, license and collaboration agreements), which include upfront payments for licenses or options to obtain licenses, payments for research and development services and milestone payments.

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

	*Three Months Ended March 31,*
	*2024*		*2023*
Pfizer	$	6	$	1,423
AstraZeneca		—		434
Servier		47		(74	)
Genentech		—		153
Total Revenue	$	53	$	1,936

As of March 31, 2024, 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*
Pfizer	$	759	$	450
Servier		105		97
Boston Pharmaceuticals		85		265
Total potential milestone payments	$	949	$	812

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 fee and that option expires in May 2024. 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. As of March 31, 2024, any variable consideration related to the exercise of such options is considered fully constrained.

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 BOS-342, also referred to as PRS-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 BOS-342. The Company received an upfront payment and is further entitled to receive development, regulatory and sales-based milestone payments, tiered royalties up to low double-digits on sales of 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 recognized the full transaction price as revenue in 2021 and has 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 hepatocellular carcinoma (HCC), for which the Company received a milestone payment of $2.5 million.

Pfizer (formerly Seagen)

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

Under the terms of the Pfizer Agreements, the companies agreed to pursue multiple antibody-Anticalin fusion proteins during the research phase. The Pfizer Agreements provide Pfizer an option to select up to three programs for further development, which Pfizer did, and Pfizer is responsible for developing, funding and commercializing each of these programs.

On March 24, 2021, the Company entered into a Second Pfizer Amendment (formerly the Second Seagen Amendment), to amend the existing immuno-oncology collaboration agreement relating to joint development and commercial rights for one program in the alliance. Under the Second Pfizer Amendment, the Company retains a co-promotion option in the United States for one program, while Pfizer remains solely responsible for the development and overall commercialization of that program. The Company will also be entitled to increased royalties from that program if it chooses to exercise the co-promotion option.

Under the Pfizer 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. 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, with the exception of the $5.0 million milestone as described in the following paragraph.

In January 2023, the Company achieved a milestone for the first program in the Pfizer 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, Pfizer and the Company entered into an amendment of the Second Pfizer Amendment that provides Pfizer with collaboration product licenses and no changes to the amounts achievable under the collaboration agreement. The effect of the September 2023 amendment was to transfer responsibility for substantially all activities previously performed by the Company to Pfizer. Subsequently, in December 2023, the transfer of the programs was fully approved by the combined joint steering committee. Accordingly, the Company recognized revenue of approximately $10.1 million for the delivery on its performance obligations related to the two programs for the year ended December 31, 2023. With this amendment, the Company has satisfied all remaining obligations under the collaboration.

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. The first two discovery-stage programs were discontinued in 2022. The third discovery-stage program was discontinued in the second quarter of 2023, which led to recognition of $4.0 million of revenue in that same quarter.

In June 2023, based on non-clinical safety findings in a 13-week toxicology study of elarekibep in non-human primates previously disclosed by the Company, AstraZeneca notified us of its decision to discontinue and cease dosing in the ongoing clinical studies of elarekibep. There was no effect to revenue as a result of the discontinuation of this program.

On July 17, 2023, as a result of the non-clinical safety finding in the 13-week toxicology study of elarekibep in non-human primates, AstraZeneca notified the Company of its intention to terminate the AstraZeneca Collaboration Agreement and the AstraZeneca Platform License, effective October 15, 2023. As a result of this, the remaining amount of current deferred revenue, or $3.5 million, related to the fourth discovery-stage program 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 determined that it would not continue development of the programs under the AstraZeneca Agreements.

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.

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 of co-development and commercialization of S095012, also referred to asPRS- 344, a 4- 1BB/PD- L1 bispecific Mabcalin protein, in the United States. 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 S095012 in the United States. 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 S095012 under the terms of the Servier Agreement. With the decision to opt out of co-development of S095012 , the Company recognized the remaining revenue under the collaboration, or $4.7 million, in 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 months ended March 31, 2024. There were no reductions to deferred revenue for the three months ended March 31, 2024 and reductions to deferred revenue were $1.7 million for the three months ended March 31, 2023.

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.

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Note 4 - Grant Income	3 Months Ended
Mar. 31, 2024
Notes to Financial Statements
Government Assistance [Text Block]	4. Grant Income One of the Company's proprietary respiratory assets, PRS-220, an oral inhaled Anticalin protein targeting connective tissue growth factor, or CTGF, was being developed as a local treatment for idiopathic pulmonary fibrosis, and other forms for fibrotic lung disorders. In June 2021, the Company received a €14.2 million (approximately $17.0 million) grant from the Bavarian Ministry of Economic Affairs, Regional Development and Energy (the Bavarian Grant) supporting research and development for post-acute sequelae of SARS-CoV-2 infection (PASC) pulmonary fibrosis, or PASC-PF, also known as post-COVID-19 syndrome pulmonary fibrosis, or “long COVID”. The Bavarian Grant provides partial reimbursement for qualifying research and development activities on PRS-220, including drug manufacturing costs, activities and costs to support an IND filing, and Phase 1 clinical trials costs. The Bavarian Grant provides reimbursement of qualifying costs incurred through December 2023, with submission for reimbursements allowed through February 2024, which was successfully completed by the Company. The timing of reimbursements follows the expected development timeline of this program. Qualifying costs incurred may exceed the annual grant funding thresholds. 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 amounts received under the grant.

Note 4 - Grant Income

3 Months Ended

Mar. 31, 2024

Government Assistance [Text Block]

4. Grant Income

One of the Company's proprietary respiratory assets, PRS-220, an oral inhaled Anticalin protein targeting connective tissue growth factor, or CTGF, was being developed as a local treatment for idiopathic pulmonary fibrosis, and other forms for fibrotic lung disorders. In June 2021, the Company received a €14.2 million (approximately $17.0 million) grant from the Bavarian Ministry of Economic Affairs, Regional Development and Energy (the Bavarian Grant) supporting research and development for post-acute sequelae of SARS-CoV-2 infection (PASC) pulmonary fibrosis, or PASC-PF, also known as post-COVID-19 syndrome pulmonary fibrosis, or “long COVID”.

The Bavarian Grant provides partial reimbursement for qualifying research and development activities on PRS-220, including drug manufacturing costs, activities and costs to support an IND filing, and Phase 1 clinical trials costs. The Bavarian Grant provides reimbursement of qualifying costs incurred through December 2023, with submission for reimbursements allowed through February 2024, which was successfully completed by the Company. The timing of reimbursements follows the expected development timeline of this program. Qualifying costs incurred may exceed the annual grant funding thresholds.

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 amounts received under the grant.

Note 2 - Summary of Significant Accounting Policies - Schedule of Property, Plant and Equipment, Useful Lives (Details)	Mar. 31, 2024
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

3 Months Ended

Mar. 31, 2024

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 March 31, 2024 and 2023, and as calculated using the treasury stock method, approximately 0.5 million and 0.6 million of weighted average shares, respectively, were excluded from the calculation of diluted weighted average shares outstanding as their effect was antidilutive.

Note 5 - Cash, Cash Equivalents and Investments - Cash Equivalents and Investments Carried at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Cash equivalents	$ 16,064
Total		$ 22,194
Fair Value, Inputs, Level 1 [Member]
Cash equivalents	16,064
Total		22,194
Fair Value, Inputs, Level 2 [Member]
Cash equivalents	0
Total		0
Fair Value, Inputs, Level 3 [Member]
Cash equivalents	0
Total		0
Money Market Funds [Member]
Cash equivalents	8,143	13,224
Money Market Funds [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents	8,143	13,224
Money Market Funds [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash equivalents	0	0
Money Market Funds [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash equivalents	0	0
US Treasury Securities [Member]
Cash equivalents	7,921
Investments		8,970
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents	7,921
Investments		8,970
US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Cash equivalents	0
Investments		0
US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
Cash equivalents	$ 0
Investments		$ 0

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

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Note 9 - Stockholders' Equity

3 Months Ended

Mar. 31, 2024

Equity [Text Block]

9. Stockholders’ Equity

Effective at 5:00 p.m. Eastern Time on April 22, 2024, the Company effected a 1-for-80 Reverse Split of its common stock. All references to shares of common stock outstanding, average number of shares outstanding and per share amounts in this Quarterly Report on Form 10-Q have been restated to reflect the Reverse Split on a retroactive basis.

The Company had 3,750,000 shares authorized and 1,236,688 shares of common stock issued and outstanding as of March 31, 2024 and December 31, 2023, 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 March 31, 2024 and December 31, 2023. Preferred stock has a par value of $0.001 per share, converts on a factor of 13.34 common shares for each preferred share, and consists of the following:

•

Series A Convertible, 85 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively.

•

Series B Convertible, 4,026 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively.

•

Series C Convertible, 3,506 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively.

•

Series D Convertible, 3,000 shares issued and outstanding at March 31, 2024 and December 31, 2023, respectively.

•

Series E Convertible, 5,000 shares issued and outstanding at March 31, 2024 and December 31, 2023, 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 43,750 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 19,746 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 28,125 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 37,500 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 75,000 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 9,375 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 three months ended March 31, 2024 and 2023, the Company did not sell any shares under the ATM program.

The Company is currently subject to the SEC general instructions of Form S-3 known as the “baby shelf rules.” Under these instructions, the amount of funds the Company can raise through primary public offerings of securities in any 12-month period using its registration statement on Form S-3 is limited to one-third of the aggregate market value of the shares of the Company’s common stock held by non-affiliates. Therefore, the Company will be limited in the amount of proceeds it is able to raise by selling shares of its common stock using its Form S-3, including under the ATM Program, until such time as its public float exceeds $75 million.

The entire disclosure for equity.

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Note 1 - Corporate Information

3 Months Ended

Mar. 31, 2024

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

1. Corporate Information

Pieris Pharmaceuticals, Inc., or the Company or Pieris, was founded in May 2013, and acquired 100% interest in Pieris Pharmaceuticals GmbH (formerly Pieris AG, a German company which was founded in 2001) in December 2014. Pieris Pharmaceuticals, Inc. and its wholly-owned subsidiaries, hereinafter collectively Pieris, or the Company, is a biopharmaceutical company that, prior to July of 2023, discovered and developed Anticalin-based drugs to target validated disease pathways in unique and transformative ways. Pieris’ clinical pipeline consists of immuno-oncology, or IO, programs partnered with several major multi-national pharmaceutical companies. Pieris' corporate headquarters is located in Boston, Massachusetts. Pieris also maintains office space in Hallbergmoos, Germany.

The Company’s core Anticalin technology and platform was developed in Germany.

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 related to events that impacted the Company’s inhaled respiratory franchise in connection with AstraZeneca's discontinuation of enrollment of the Phase 2a study for elarekibep, an inhaled IL-4Rα antagonist Anticalin protein to treat uncontrolled asthma. As part of this initiative, the Company engaged Stifel, Nicolaus & Company, Incorporated to serve as its advisor in its review of strategic transactions.

Also on July 18, 2023, the Company’s Board of Directors approved a reduction in the Company’s workforce by approximately 70%. Since July of 2023, and through March 31, 2024, the Company took additional steps to reduce its operating footprint including terminating its remaining lease obligations in Germany and winding down its proprietary inhaled respiratory programs. The Company also has opted out and terminated programs where possible to reduce operating costs. Further reductions in the workforce have occurred based upon these actions. As a result, the Company has incurred approximately $7.5 million of severance costs and other related termination benefits in 2023 as the service period to earn such benefits is considered complete. The Company expects termination benefits to be paid through the end of 2024.

On March 27, 2024, the Company announced the implementation of a new strategy along with relevant cost-saving measures that are expected to extend its cash runway into at least 2027, while maximizing its ability to capture the potential milestones from its partnered 4-1BB bispecific Mabcalin™ protein IO assets. The Company may be entitled to aggregate milestones of up to approximately $20.0 million upon first patient dosed in the Phase 2 trials for SGN-BB228, S095012 (formerly PRS-344) and BOS-342, which are all currently in Phase 1 clinical development, and up to approximately $55.0 million upon first patient dosed in pivotal clinical trials for SGN-BB228, S095012 and BOS-342. To support this new strategy, the Company plans to discontinue all of its research and development efforts which it expects to complete by the middle of 2024, implement a workforce reduction that will impact additional employees and the executive leadership team which is expected to be implemented in the second quarter of 2024, and reduce the size of its Board of Directors, which is also expected to be implemented in the second quarter of 2024. In addition to the alliance management activities for its partnered programs, the Company remains committed to obtaining value for its products in prior development, including cinrebafusp alfa, as well as its proprietary platform capabilities by pursuing potential out-licensing or sales transactions. In addition to these potential transactions, the Company may also, from time-to-time, consider strategic opportunities that it believes may increase stockholder value.

As of March 31, 2024, cash and cash equivalents were $19.1 million. For the three months ended March 31, 2024 and 2023, the Company had net losses of $4.9 million and $13.2 million, respectively. The Company has incurred net losses since inception and had an accumulated deficit of $319.9 million as of March 31, 2024. 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.

The Company has historically devoted substantially all of its financial resources and efforts to research and development and general and administrative expenses to support the discovery and development of Anticalin-based drugs. Going forward, as part of the Company's decision to implement measures to maximize its ability to capture potential milestones from its partnered programs with Pfizer, Boston Pharmaceuticals, and Servier (all as defined in Note 3 below), the Company plans to discontinue all research and development efforts and reduce discretionary expenditures and other fixed or variable personnel costs. The Company believes that its currently available funds will be sufficient to fund its operations through at least the next twelve 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. If actual results are different from management’s estimates, the Company may need to seek additional funding.

Note 10 - Leases

3 Months Ended

Mar. 31, 2024

Lessee, Operating Leases [Text Block]

10. Leases

The Company generally conducts its operational functions in the United States remotely.

In October 2018, Pieris Pharmaceuticals GmbH entered into a 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, provided an initial rental term of 12.5 years, and a rental area of approximately 105,000 square feet.

In December 2023, Pieris Pharmaceuticals GmbH entered into an agreement to terminate the Hallbermoos Lease, or the Lease Termination Agreement. Under the terms of the Lease Termination Agreement, Pieris Pharmaceuticals GmbH terminated the Hallbergmoos Lease in exchange for a termination fee of approximately €9.7 million, and vacated the majority of the premises by December 31, 2023, while continuing to occupy, through June 2024, a limited portion of the office space and using another portion of the former lab space to house its assets being held for sale.

There was no cash paid for amounts included in the measurement of the lease liabilities for the three months ended March 31, 2024. Cash paid for amounts included in the measurement of the lease liabilities were $0.5 million for the three months ended March 31, 2023.

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

	*Three Months Ended March 31,*
	*2024*		*2023*
Operating lease costs	$	—	$	288
Variable lease costs (1)		—		186
Total lease cost	$	—	$	474

(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 variable costs for the three months ended March 31, 2024 were immaterial, as the Company continues to occupy a limited portion of the space.

Note 7 - Accrued Expenses - Restructuring Activity (Details) - Severance and Benefits Costs [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)
Balance at December 31, 2023	$ 5,105
Adjustments to restructuring charges	(286)
Cash payments	(1,185)
Balance at March 31, 2024	$ 3,634

Note 5 - Cash, Cash Equivalents and Investments

3 Months Ended

Mar. 31, 2024

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

5. Cash, cash equivalents and investments

As of March 31, 2024 and December 31, 2023, cash, cash equivalents and investments comprised funds in depository, money market accounts and U.S. treasury securities. The following tables present the cash equivalents and investments carried at fair value in accordance with the hierarchy defined in Note 2 at March 31, 2024 and December 31, 2023.

	*Total*		*Quoted prices in active markets (Level 1)*		*Significant other observable inputs (Level 2)*		*Significant unobservable inputs (Level 3)*
March 31, 2024
Money market funds, included in cash equivalents	$	8,143	$	8,143	$	—	$	—
US treasuries, included in cash equivalents		7,921		7,921		—		—
Total	$	16,064	$	16,064	$	—	$	—

	*Total*		*Quoted prices in active markets (Level 1)*		*Significant other observable inputs (Level 2)*		*Significant unobservable inputs (Level 3)*
December 31, 2023
Money market funds, included in cash equivalents	$	13,224	$	13,224	$	—	$	—
Investments - US treasuries		8,970		8,970		—		—
Total	$	22,194	$	22,194	$	—	$	—

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 March 31, 2024.

The Company recorded no realized gains or losses from the maturity of available-for-sale securities during the three months ended March 31, 2024 and recorded $0.1 million in realized losses from the maturity of available-for-sale securities during the three months ended March 31, 2023.

Note 2 - Summary of Significant Accounting Policies (Details Textual)	Apr. 22, 2024
Reverse Stock Split [Member] \| Subsequent Event [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	80

Note 7 - Accrued Expenses (Tables)

3 Months Ended

Mar. 31, 2024

Schedule of Accrued Liabilities [Table Text Block]

	*March 31,*		*December 31,*
	*2024*		*2023*
Compensation expense	$	4,190	$	6,448
Research and development fees		719		968
Accrued accounts payable		549		558
Other current liabilities		335		363
Accrued license obligations		222		213
Total	$	6,015	$	8,550

Schedule of Restructuring Reserve by Type of Cost [Table Text Block]

	*Severance and Benefits Costs*
Balance at December 31, 2023	$	5,105
Adjustments to restructuring charges	$	(286	)
Cash payments		(1,185	)
Balance at March 31, 2024	$	3,634

Note 7 - Accrued Expenses - Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Compensation expense	$ 4,190	$ 6,448
Research and development fees	719	968
Accrued accounts payable	549	558
Other current liabilities	335	363
Accrued license obligations	222	213
Total	$ 6,015	$ 8,550

Note 7 - Accrued Expenses

3 Months Ended

Mar. 31, 2024

Accounts Payable and Accrued Liabilities Disclosure [Text Block]

7. Accrued Expenses

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

	*March 31,*		*December 31,*
	*2024*		*2023*
Compensation expense	$	4,190	$	6,448
Research and development fees		719		968
Accrued accounts payable		549		558
Other current liabilities		335		363
Accrued license obligations		222		213
Total	$	6,015	$	8,550

The compensation expense line item in the above table includes both severance and benefit costs associated with the Company's corporate restructuring actions announced in 2023, inclusive of those employees retained as the service period to earn such benefits is considered complete. The Company recognized restructuring expenses consisting of one-time cash severance payments and other employee-related costs. Severance pay and related costs for certain retained employees are estimated to be paid through the end 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.

The following table includes a roll forward of the restructuring activity and payments recorded for the three months ended March 31, 2024 (in thousands):

	*Severance and Benefits Costs*
Balance at December 31, 2023	$	5,105
Adjustments to restructuring charges	$	(286	)
Cash payments		(1,185	)
Balance at March 31, 2024	$	3,634

Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Preferred Stock [Member]	Common Stock [Member]	Receivables from Stockholder [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2022	16	931
Balance at Dec. 31, 2022	$ 0	$ 1	$ 0	$ 318,603	$ (254)	$ (290,421)	$ 27,929
Net loss	0	0	0	0	0	(13,183)	(13,183)
Stock based compensation expense	0	0	0	884	0	0	884
Foreign currency translation adjustment	0	0	0	0	(242)	0	(242)
Unrealized gain on investments	0	0	0	0	70	0	70
Stock based compensation expense	$ 0	$ 0	0	(884)	0	0	(884)
Balance (in shares) at Mar. 31, 2023	16	931
Balance at Mar. 31, 2023	$ 0	$ 1	0	319,487	(426)	(303,604)	15,458
Balance (in shares) at Dec. 31, 2023	16	1,237
Balance at Dec. 31, 2023	$ 0	$ 1	0	341,693	28	(314,964)	26,758
Net loss	0	0	0	0	0	(4,892)	(4,892)
Stock based compensation expense	0	0	0	472	(0)	0	472
Foreign currency translation adjustment	0	0	0	0	(373)	0	(373)
Unrealized gain on investments	0	0	0	0	(1)	0	(1)
Stock based compensation expense	$ 0	$ 0	0	(472)	0	0	(472)
Balance (in shares) at Mar. 31, 2024	16	1,237
Balance at Mar. 31, 2024	$ 0	$ 1	$ 0	$ 342,165	$ (346)	$ (319,856)	$ 21,964

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

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Note 1 - Corporate Information (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 27, 2024	Dec. 31, 2023	Jul. 18, 2023	May 31, 2013
Reduction in Workforce, Percentage					70.00%
Reduction in Workforce, Cost				$ 7,500
Cash, Cash Equivalents, and Short-Term Investments	$ 19,100
Net Income (Loss) Attributable to Parent	(4,892)	$ (13,183)
Retained Earnings (Accumulated Deficit)	$ (319,856)			$ (314,964)
B P Assets X I I Inc [Member] \| License [Member] \| Exclusive Product License Agreement [Member] \| Phase 2 Trials [Member]
Contracts Receivable, Claims and Uncertain Amounts			$ 20,000
B P Assets X I I Inc [Member] \| License [Member] \| Exclusive Product License Agreement [Member] \| Pivotal Clinical Trials [Member]
Contracts Receivable, Claims and Uncertain Amounts			$ 55,000
Pieris Pharmaceuticals GmbH [Member]
Business Acquisition, Percentage of Voting Interests Acquired						100.00%

Note 6 - Assets Held for Sale (Tables)

3 Months Ended

Mar. 31, 2024

Disclosure of Long-Lived Assets Held-for-Sale [Table Text Block]

	*March 31,*		*December 31,*
	*2024*		*2023*
Laboratory furniture and equipment	$	180	$	1,967
Office furniture and equipment		16		221
Assets held for sale	$	196	$	2,188

Note 9 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Millions					1 Months Ended		3 Months Ended
	Apr. 22, 2024	Jun. 21, 2023 shares	Jun. 22, 2022 shares	Jun. 25, 2021 shares	Nov. 30, 2022 USD ($)	Aug. 31, 2021 USD ($)	Mar. 31, 2024 $ / shares shares	Dec. 31, 2023 $ / shares shares	Dec. 31, 2020 shares
Common Stock, Shares Authorized (in shares)							3,750,000	3,750,000
Common Stock, Shares, Issued (in shares)							1,236,688	1,236,688
Common Stock, Shares, Outstanding (in shares)							1,236,688	1,236,688
Common Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares							$ 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, Shares Outstanding, Ending Balance (in shares)							15,617	15,617
Preferred Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares							$ 0.001	$ 0.001
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)							13.34
Jefferies L L C [Member] \| At the Market Offering [Member]
Sale of Stock, Authorized Amount \| $					$ 75	$ 50
Stock Issued During Period, Shares, New Issues (in shares)							0
Employee Director And Consultant Equity Incentive Plan2020 [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)									43,750
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)									19,746
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)		75,000	37,500	28,125
The 2023 Employee Stock Purchase Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance (in shares)							9,375
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
Reverse Stock Split [Member] \| Subsequent Event [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio	80

Note 6 - Assets Held for Sale

3 Months Ended

Mar. 31, 2024

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

6. Assets Held for Sale

As of March 31, 2024 and December 31, 2023, assets held for sale are summarized as follows (in thousands):

	*March 31,*		*December 31,*
	*2024*		*2023*
Laboratory furniture and equipment	$	180	$	1,967
Office furniture and equipment		16		221
Assets held for sale	$	196	$	2,188

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 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. As a result of this decision, the property and equipment met the criteria for held-for-sale accounting.

The 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 and office 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 hierarchy. In the first quarter of 2024, the Company conducted an auction, with the assistance of a third party, of its assets held for sale. After the conclusion of the auction, the Company has recovered substantially all of the total net book value of the assets held for sale and did not record a gain or loss for assets sold in the first quarter of 2024. The Company has further plans to sell all remaining assets in the second quarter of 2024.

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

Note 3 - Revenue (Tables)

3 Months Ended

Mar. 31, 2024

Disaggregation of Revenue [Table Text Block]

	*Three Months Ended March 31,*
	*2024*		*2023*
Pfizer	$	6	$	1,423
AstraZeneca		—		434
Servier		47		(74	)
Genentech		—		153
Total Revenue	$	53	$	1,936

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

	*Research, Development, Regulatory & Commercial Milestones*		*Sales Milestones*
Pfizer	$	759	$	450
Servier		105		97
Boston Pharmaceuticals		85		265
Total potential milestone payments	$	949	$	812

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 19,084	$ 17,396
Short term investments	0	8,970
Accounts receivable	1,842	572
Receivable from public grants	3,071	3,141
Other receivables	2,332	2,326
Assets held for sale, property and equipment	196	2,188
Prepaid expenses and other current assets	2,972	4,087
Total current assets	29,497	38,680
Current liabilities:
Accounts payable	1,518	3,372
Accrued expenses and other current liabilities	6,015	8,550
Total current liabilities	7,533	11,922
Stockholders’ equity:
Preferred stock	0	0
Common stock	1	1
Additional paid-in capital	342,165	341,693
Accumulated other comprehensive loss	(346)	28
Accumulated deficit	(319,856)	(314,964)
Total stockholders’ equity	21,964	26,758
Total liabilities and stockholders’ equity	$ 29,497	$ 38,680

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

3 Months Ended

Mar. 31, 2024

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)*
March 31, 2024
Money market funds, included in cash equivalents	$	8,143	$	8,143	$	—	$	—
US treasuries, included in cash equivalents		7,921		7,921		—		—
Total	$	16,064	$	16,064	$	—	$	—

	*Total*		*Quoted prices in active markets (Level 1)*		*Significant other observable inputs (Level 2)*		*Significant unobservable inputs (Level 3)*
December 31, 2023
Money market funds, included in cash equivalents	$	13,224	$	13,224	$	—	$	—
Investments - US treasuries		8,970		8,970		—		—
Total	$	22,194	$	22,194	$	—	$	—

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating activities:
Net loss	$ (4,892)	$ (13,183)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization (accretion)	(30)	605
Right-of-use asset (accretion) amortization	0	(34)
Stock-based compensation	472	884
Proceeds on sale of fixed assets	866	0
Prepaid rent	556	0
Realized investment gains	0	53
Other non-cash transactions	(5)	72
Changes in operating assets and liabilities	(3,963)	607
Net cash used in operating activities	(6,996)	(10,996)
Investing activities:
Purchases of property and equipment	0	(48)
Proceeds from maturity of investments	9,000	13,495
Purchases of investments	0	(1,544)
Net cash provided by investing activities	9,000	11,903
Effect of exchange rate change on cash and cash equivalents	(316)	200
Net increase in cash and cash equivalents	1,688	1,107
Cash and cash equivalents at beginning of period	17,396	38,635
Cash and cash equivalents at end of period	19,084	39,742
Supplemental cash flow disclosures:
Net unrealized gain (loss) on investments	$ (1)	$ 70

Document And Entity Information - shares	3 Months Ended
Document And Entity Information - shares	Mar. 31, 2024	May 09, 2024
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	Q1
Document Fiscal Year Focus	2024
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2024
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		1,320,240

Note 3 - Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Total revenue	$ 53	$ 1,936
Pfizer [Member]
Total revenue	6	1,423
Astra Zeneca A B [Member]
Total revenue	0	434
Les Laboratoires Servier And Institut De Recherches Internationales Servier [Member]
Total revenue	47	(74)
Genentech [Member]
Total revenue	$ 0	$ 153

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).

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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-05(b)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477314/942-235-S99-1

Reference 26: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2

Note 2 - Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2024

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 10 - Leases (Tables)

3 Months Ended

Mar. 31, 2024

Lease, Cost [Table Text Block]

	*Three Months Ended March 31,*
	*2024*		*2023*
Operating lease costs	$	—	$	288
Variable lease costs (1)		—		186
Total lease cost	$	—	$	474

Note 6 - Assets Held for Sale - Summary of Assets Held for Sale (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Net Book Value	$ 196	$ 2,188
Laboratory Furniture and Equipment [Member]
Net Book Value	180	1,967
Office Furniture and Equipment [Member]
Net Book Value	$ 16	$ 221

Note 3 - Revenue (Details Textual) $ in Thousands	1 Months Ended		3 Months Ended			12 Months Ended
Note 3 - Revenue (Details Textual) $ in Thousands	Aug. 31, 2023 USD ($)	Jan. 31, 2023 USD ($)	Mar. 31, 2024 USD ($)	Jun. 30, 2023 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2017	Sep. 30, 2023 USD ($)	May 19, 2021 USD ($)	Feb. 08, 2018	May 02, 2017
Increase in Contract With Customer Liability			$ 0
Decrease in Contract with Customer, Liability			$ 0		$ 1,700
Amendment of the Second Seagen Amendment [Member]
Revenue from Contract with Customer, Excluding Assessed Tax						$ 10,100
Genentech [Member]
Number Of Initial Research Programs										2
Contract with Customer, Liability, Revenue Recognized				$ 12,500
Number Of Optional Additional Research Programs										2
B P Assets X I I Inc [Member] \| Exclusive Product License Agreement [Member]
Contract with Customer, Milestone Payment Received	$ 2,500
Seattle Genetics Inc. [Member] \| License and Collaboration Agreement [Member]
Number of Research Programs											3
Seattle Genetics Inc. [Member] \| Collaborative Arrangement [Member]
Revenue from Contract with Customer, Excluding Assessed Tax		$ 5,000					$ 5,000
Astra Zeneca A B [Member] \| License and Collaboration Agreement [Member]
Contract with Customer, Liability, Revenue Recognized				$ 4,000
Contract with Customer, Liability, Current									$ 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]
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
Number of Programs								5
License [Member] \| Genentech [Member]
Contract with Customer, Liability, Total										$ 20,000

Significant Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2024

Accounting Policies [Abstract]

Basis of Accounting, Policy [Policy Text Block]

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 months ended March 31, 2024 are not necessarily indicative of results that may be expected for the year ending December 31, 2024. 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, 2023, which was filed with the SEC on March 29, 2024.

Use of Estimates, Policy [Policy Text Block]

Basis of Presentation and Use of Estimates

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

Effective at 5:00 p.m. Eastern Time on April 22, 2024, the Company effected a 1-for-80 reverse stock split of its common stock, or the Reverse Split, with any fractional shares resulting from the Reverse Split rounded up to the next whole share of common stock. All references to shares of common stock outstanding, average number of shares outstanding and per share amounts in this Quarterly Report on Form 10-Q have been restated to reflect the Reverse Split on a retroactive basis.

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; 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 and Cash Equivalents, Policy [Policy Text Block]

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

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 of Financial Instruments, Policy [Policy Text Block]

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, Plant and Equipment, Policy [Policy Text Block]

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 Topic 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 costs 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.

Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block]

Impairment of Long-lived Assets

The Company reviews its long-lived assets to be held and used for impairment whenever events or changes in business circumstances indicate that the carrying amount of the assets may not be fully recoverable. The Company evaluates the realizability of its long-lived assets based on profitability and cash flow expectations for the related asset. Any write-downs are treated as permanent reductions in the carrying amount of the assets.

Revenue [Policy Text Block]

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 Topic 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 Topic 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 Topic 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 Assistance [Policy Text Block]

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.

Lessee, Leases [Policy Text Block]

Leases

In accordance with accounting standards update, or 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.

When a lease is terminated in its entirety, the corresponding lease liability and right-of-use asset are adjusted to zero. Any difference between the carrying amounts of the right-of-use asset and lease liability as compared to the termination payment is recorded in the statement of operations as a gain or loss.

New Accounting Pronouncements, Policy [Policy Text Block]

Recent Accounting Pronouncements Not Yet Adopted

On December 14, 2023, the FASB issued ASU 2023-09, or ASU 2023-09, Improvements to Income Tax Disclosures. The standard requires disaggregated information about a reporting entity’s effective tax rate reconciliation as well as information on income taxes paid. The standard is intended to benefit investors by providing more detailed income tax disclosures that would be useful in making capital allocation decisions. ASU 2023-09 applies to all entities subject to income taxes. For public business entities, the new requirements will be effective for annual periods beginning after December 15, 2024. For entities other than public business entities, the requirement will be effective for annual periods beginning after December 15, 2025. The Company is currently evaluating the effect on the unaudited condensed consolidated financial statements.

Note 8 - Net Income (Loss) Per Share (Details Textual) - shares shares in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	0.5	0.6

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Revenue
Customer revenue	$ 6	$ 2,010
Collaboration revenue	47	(74)
Total revenue	53	1,936
Operating expenses
Research and development	1,218	13,424
General and administrative	4,138	4,023
Total operating expenses	5,356	17,447
Loss from operations	(5,303)	(15,511)
Other income (expense)
Interest income	240	357
Grant income	0	2,028
Other income (loss)	171	(57)
Net loss	(4,892)	(13,183)
Other comprehensive income loss:
Foreign currency translation	(373)	(242)
Unrealized gain (loss) on available-for-sale securities	(1)	70
Comprehensive loss	$ (5,266)	$ (13,355)
Net loss per share
Basic and diluted (in dollars per share)	$ (3.95)	$ (14.15)
Weighted average number of common shares outstanding
Basic and diluted (in shares)	1,237	931

Note 2 - Summary of Significant Accounting Policies

3 Months Ended

Mar. 31, 2024