0001437749-24-034891 | 10-Q | XBRL Viewer | Pieris Pharmaceuticals INC

Schedule of Accrued Liabilities [Table Text Block]

	*September 30,*		*December 31,*
	*2024*		*2023*
Compensation expense	$	2,306	$	6,448
Research and development fees		—		968
Accrued accounts payable		60		558
Other current liabilities		1,031		363
Accrued license obligations		56		213
Total	$	3,453	$	8,550

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

	*Severance and Benefits Costs*
Balance at June 30, 2024	$	2,850
Adjustments to restructuring charges	$	183
Cash payments		(805	)
Balance at September 30, 2024	$	2,228

	*Severance and Benefits Costs*
Balance at December 31, 2023	$	5,105
Adjustments to restructuring charges	$	(86	)
Cash payments		(2,791	)
Balance at September 30, 2024	$	2,228

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Operating activities:
Net loss	$ (11,369)	$ (19,959)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization (accretion)	(30)	2,102
Right-of-use asset accretion	0	(98)
Stock-based compensation	1,223	2,898
Gain on sale of fixed assets	(225)
Asset impairment	0	14,893
Prepaid rent	1,118	0
Realized investment losses	0	(53)
Other non-cash transactions	864	(129)
Changes in operating assets and liabilities	89	(33,804)
Net cash used in operating activities	(8,330)	(34,150)
Investing activities:
Purchases of property and equipment	0	(184)
Proceeds from maturity of investments	9,000	24,007
Proceeds on sale of fixed assets	2,318	0
Purchases of investments	0	(15,270)
Net cash provided by investing activities	11,318	8,553
Financing activities:
Proceeds from employee stock purchase plan	0	52
Proceeds from issuance of common stock resulting from ATM sales, net of $0.7 million in transaction costs	0	19,729
Net cash provided by financing activities	0	19,781
Effect of exchange rate change on cash and cash equivalents	(1,021)	75
Net increase in cash and cash equivalents	1,967	(5,741)
Cash and cash equivalents at beginning of period	17,396	38,635
Cash and cash equivalents at end of period	19,363	32,894
Supplemental cash flow disclosures:
Net unrealized gain (loss) on investments	$ (1)	$ 74

Note 3 - Revenue (Tables)

9 Months Ended

Sep. 30, 2024

Disaggregation of Revenue [Table Text Block]

	*Three Months Ended September 30,*				*Nine Months Ended September 30,*
	*2024*		*2023*		*2024*		*2023*
Pfizer (formerly Seagen)	$	—	$	9,179	$	6	$	14,088
AstraZeneca		—		3,909		—		8,399
Servier		—		3,951		47		3,846
Genentech		—		—		—		12,697
Boston Pharmaceuticals		—		2,481		—		2,481
Total Revenue	$	—	$	19,520	$	53	$	41,511

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

	*Research, Development, Regulatory & Commercial Milestones*		*Sales Milestones*
Pfizer (formerly Seagen)	$	759	$	450
Boston Pharmaceuticals		85		265
Total potential milestone payments	$	844	$	715

Note 5 - Cash, Cash Equivalents and Investments - Cash Equivalents and Investments Carried at Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Cash equivalents	$ 11,893
Total		$ 22,194
Fair Value, Inputs, Level 1 [Member]
Cash equivalents	11,893
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	11,893	13,224
Money Market Funds [Member] \| Fair Value, Inputs, Level 1 [Member]
Cash equivalents	11,893	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]
Investments		8,970
US Treasury Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Investments		8,970
US Treasury Securities [Member] \| Fair Value, Inputs, Level 2 [Member]
Investments		0
US Treasury Securities [Member] \| Fair Value, Inputs, Level 3 [Member]
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 11 - Merger Agreement with Palvella Therapeutics, Inc.

9 Months Ended

Sep. 30, 2024

Business Combination Disclosure [Text Block]

11. Merger Agreement with Palvella Therapeutics, Inc.

On July 23, 2024, the Company and its wholly-owned subsidiary, Merger Sub entered into the Merger Agreement with Palvella whereby Merger Sub will merge with and into Palvella, with Palvella continuing as a wholly-owned subsidiary of the Company and the surviving corporation of the Merger. If the Merger is completed, the business of Palvella will continue as the business of the combined organization. Consummation of the Merger is contingent on certain closing conditions as identified in the Merger Agreement, including among others, (1) approval by the Company's stockholders of the Required Voting Proposals, as defined in the Merger Agreement, (2) approval by the Palvella stockholders of the adoption of the Merger Agreement, (3) Nasdaq’s approval of the listing of the shares of the Company's common stock to be issued in connection with the Merger, (4) the effectiveness of the Registration Statement, and (5) consummation of the PIPE Financing, all in accordance with the terms of the Purchase Agreement.

Each party’s obligation to consummate the Merger is also subject to other specified customary conditions, including the representations and warranties of the other party being true and correct as of the date of the Merger Agreement and as of the closing date of the Merger, generally subject to an overall material adverse effect qualification, the performance in all material respects by the other party of its obligations under the Merger Agreement required to be performed on or prior to the date of the closing of the Merger and the absence of any material adverse effect affecting the other party that is continuing on the closing date.

Subject to the terms and conditions of the Merger Agreement, at the Effective Time, as defined in the Merger Agreement, (i) each then-outstanding share of Palvella capital stock will be converted into the right to receive a number of shares of the Company's common stock equal to the Exchange Ratio as defined in the Merger Agreement; and (ii) each then-outstanding Palvella stock option to purchase Palvella common stock will be assumed by the Company, subject to adjustment as set forth in the Merger Agreement. In connection with the Merger, and contingent on the approval of the Company's stockholders, the Company intends to amend the amended and restated articles of incorporation of the Company to increase the number of shares of authorized common stock, change the corporate name of the Company to “Palvella Therapeutics, Inc.” and adopt a new 2024 equity incentive plan. The provisions for calculating the Exchange Ratio are set forth in the Merger Agreement, and assume a valuation for Palvella equal to $95 million, and a valuation for Pieris equal to $21 million, provided, that (a) if Pieris’ net cash as of the closing is greater than $11 million, then Pieris’ valuation will be adjusted upwards on a dollar-for-dollar basis by the difference of: (i) Pieris' net cash, minus (ii) $11 million, and (b) if Pieris’ net cash is less than $11 million, then Pieris’ valuation will be adjusted downwards on a dollar-for-dollar basis by the difference of: (i) $11 million, minus (ii) Pieris’ net cash.

For the purposes of calculating the Exchange Ratio for each of Pieris and Palvella, the total number of shares of capital stock of such company issued and outstanding immediately prior to the Merger, expressed on a fully-diluted and as-converted to common stock basis, calculated using the treasury stock method, will be included in the calculation of the Exchange Ratio. Shares of Pieris common stock underlying Pieris stock options outstanding immediately prior to the Effective Time with an exercise price per share of less than the volume weighted average closing trading price of a share of Pieris common stock on the Nasdaq for the five consecutive trading days ending five trading days immediately prior to the date upon which the Merger occurs will be deemed to be outstanding, calculated using the treasury stock method, and all shares of Palvella common stock underlying outstanding Palvella stock options, warrants and other derivative securities will be deemed to be outstanding, calculated using the treasury stock method, subject to certain exceptions set forth in the Merger Agreement.

Under the terms of the Merger Agreement, on a pro forma basis, it is expected that upon the closing of the Merger, pre-Merger Company stockholders will own approximately 18% of the combined company and pre-Merger Palvella stockholders will own approximately 82% of the combined company, based on the number of shares of the Company's common stock expected to be issued in connection with the Merger, in each case, prior to the issuance of shares under a proposed concurrent private financing. The percentage of the combined company that pre-merger Palvella stockholders and pre-merger Pieris stockholders will own upon the closing of the merger is subject to further adjustment based on the amount of Pieris' net cash at the time of closing.

In connection with the Merger, Pieris will seek the approval or ratification, as applicable, by its stockholders of, among other things, (a) the issuance of the shares of Pieris common stock issuable in connection with the Merger under the rules of The Nasdaq Stock Market LLC pursuant to the terms of the Merger Agreement, (b) amendments to the amended and restated articles of incorporation of Pieris to (i) increase the number of shares of authorized common stock and (ii) change the name of Pieris to “Palvella Therapeutics, Inc.” (the approvals described in clause (a) and (b), the “Required Pieris Voting Proposals”) and (c) the adoption of a new 2024 equity incentive plan, in each case, as described in the Merger Agreement.

Each of Pieris and Palvella has agreed to customary representations, warranties and covenants in the Merger Agreement, including, among others, covenants relating to (1) using reasonable best efforts to obtain the requisite approvals of their respective stockholders, (2) non-solicitation of alternative acquisition proposals, (3) the conduct of their respective businesses during the period between the date of signing the Merger Agreement and the closing of the Merger, (4) Pieris using its commercially reasonable efforts to maintain the existing listing of the Pieris common stock on Nasdaq and Pieris causing the shares of Pieris common stock to be issued in connection with the Merger to be approved for listing on Nasdaq prior to the closing of the Merger and (5) Pieris filing with the SEC and causing to become effective a registration statement to register the shares of Pieris common stock to be issued in connection with the Merger, or Registration Statement. The Registration Statement related to the Merger was included on the Form S-4 filed by the Company with the SEC on August 9, 2024, and was subsequently amended on September 23, 2024, October 15, 2024, November 5, 2024, and November 7, 2024. The Registration Statement was declared effective by the SEC on November 8, 2024.

The transaction is expected to close in the fourth quarter of 2024 and remains subject to stockholder approval.

Contingent Value Rights

At or prior to the Effective Time, Pieris will enter into a Contingent Value Rights Agreement, or CVR Agreement, with a rights agent, or Rights Agent, pursuant to which Pieris’ pre-Merger capital stockholders will receive one contingent value right, or a CVR, for each outstanding share of Pieris common stock held by such stockholder, or share of common stock underlying preferred stock held by such stockholder, on such date. Each CVR will represent the contractual right to receive payments upon the receipt of payments by Pieris or any of its affiliates under certain strategic partner agreements, including existing collaboration agreements pursuant to which Pieris may be entitled to milestones and royalties in the future and other out-licensing agreements for certain of Pieris’ legacy assets, and upon the receipt of certain research and development tax credits in favor of Pieris or any of its affiliates, in each case as set forth in, and subject to and in accordance with the terms and conditions of, the CVR Agreement.

The contingent payments under the CVR Agreement, if they become payable, will become payable to the Rights Agent for subsequent distribution to the holders of the CVRs. In the event that no such proceeds are received, holders of the CVRs will not receive any payment pursuant to the CVR Agreement. There can be no assurance that holders of CVRs will receive any amounts with respect thereto. The right to the contingent payments contemplated by the CVR Agreement is a contractual right only and will not be transferable, except in the limited circumstances specified in the CVR Agreement. The CVRs will not be evidenced by a certificate or any other instrument and will not be registered with the SEC. The CVRs will not have any voting or dividend rights and will not represent any equity or ownership interest in Pieris or any of its affiliates. No interest will accrue on any amounts payable in respect of the CVRs.

Termination Fees

The Merger Agreement contains certain termination rights of each of Pieris and Palvella, including, subject to compliance with the applicable terms of the Merger Agreement, the right of each party to terminate the Merger Agreement to enter into a definitive agreement for a superior proposal. Upon termination of the Merger Agreement under specified circumstances, Pieris may be required to pay Palvella a termination fee of $1.0 million and Palvella may be required to pay Pieris a termination fee of $2.0 million.

Securities Purchase Agreement

On July 23, 2024, and in connection with the executed Merger Agreement, Pieris entered into a securities purchase agreement, or the Purchase Agreement, with certain investors, including BVF Partners, L.P., an existing stockholder of Pieris, or the PIPE Investors, pursuant to which, among other things, the PIPE Investors have agreed to subscribe for and purchase (either for cash or in exchange for the termination and cancellation of outstanding convertible notes issued by Palvella), and Pieris agreed to issue and sell to the PIPE Investors, an aggregate of approximately 3,154,241 of shares of Pieris common stock at a price per share equal to $13.7299 multiplied by (x) 0.315478 divided by (y) the Exchange Ratio, or the Purchase Price, subject to adjustment as set forth in the Purchase Agreement, and/or in lieu of Pieris common stock to certain purchasers who so choose, pre-funded warrants, or the Pre-Funded Warrants, to purchase up to 2,592,585 shares of Pieris common stock at a purchase price per Pre-Funded Warrant equal to the Purchase Price minus $0.001, subject to adjustment as set forth in the Purchase Agreement, or the PIPE Financing. The Purchase Agreement contains customary representations and warranties of Pieris, on the one hand, and the PIPE Investors, on the other hand, and customary conditions to closing, including the consummation of the Merger. The gross proceeds from the PIPE Financing are expected to be approximately $78.9 million, before paying estimated expenses. The closing of the PIPE Financing is expected to occur in connection with and immediately following the consummation of the Merger.

The Pre-Funded Warrants do not expire, and each Pre-Funded Warrant will be exercisable at any time after the date of issuance of such Pre-Funded Warrant, subject to a beneficial ownership limitation. A holder of a Pre-Funded Warrant may not exercise such Pre-Funded Warrant if the holder, together with its affiliates, would beneficially own more than 4.99% or 9.99% of the number of shares of Pieris common stock outstanding immediately after giving effect to such exercise, provided, however, that a holder may increase or decrease the beneficial ownership limitation by giving 61 days’ notice to the Company, but not to any percentage in excess of 19.99%.

At or prior to the closing of the PIPE Financing, Pieris will enter into a registration rights agreement, or the Registration Rights Agreement, with the PIPE Investors pursuant to which the PIPE Investors will be entitled to certain resale registration rights with respect to shares of Pieris common stock issued to the PIPE Investors and any shares of Pieris common stock issued upon exercise of the Pre-Funded Warrants. Pursuant to the Registration Rights Agreement, the Company will be required to prepare and file a resale registration statement with the SEC within 30 days following the closing of the PIPE Financing. The Company shall use its commercially reasonable efforts to cause this registration statement to be declared effective by the SEC within 90 days following the closing of the PIPE Financing (or within 120 days following the PIPE Financing if the SEC reviews the registration statement).

Note 9 - Stockholders' Equity (Details Textual) $ / shares in Units, $ in Thousands						1 Months Ended		9 Months Ended
	Aug. 07, 2024 $ / shares shares	Apr. 22, 2024	Jun. 21, 2023 shares	Jun. 22, 2022 shares	Jun. 25, 2021 shares	Nov. 30, 2022 USD ($)	Aug. 31, 2021 USD ($)	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2024 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)								1,320,240			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)								15,618			15,618
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
Preferred Stock, Shares Outstanding, Ending Balance (in shares)								15,618			15,618
Proceeds from Issuance of Common Stock \| $								$ 0	$ 19,729
Common Stock, Shares, Outstanding (in shares)								1,320,240			1,236,688
Jefferies L L C [Member] \| At the Market Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)								0	24,300,000
Shares Issued, Price Per Share (in dollars per share) \| $ / shares									$ 0.84
Sale of Stock, Authorized Amount \| $						$ 75,000	$ 50,000
Proceeds from Issuance of Common Stock \| $									$ 20,300
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)								333,145				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
Series F Preferred Stock [Member]
Preferred Stock, Shares Issued (in shares)								1			0
Preferred Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares	$ 0.01
Preferred Stock, Shares Outstanding, Ending Balance (in shares)								1			0
Preferred Stock, Voting Rights, Number of Votes Per Share	25,000,000
Series F Preferred Stock [Member] \| Board of Directors Chairman [Member]
Preferred Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares	$ 0.001
Stock Issued During Period, Shares, New Issues (in shares)	1
Shares Issued, Price Per Share (in dollars per share) \| $ / shares	$ 1
Reverse Stock Split [Member]
Stockholders' Equity Note, Stock Split, Conversion Ratio		80

Note 7 - Accrued Expenses

9 Months Ended

Sep. 30, 2024

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,*
	*2024*		*2023*
Compensation expense	$	2,306	$	6,448
Research and development fees		—		968
Accrued accounts payable		60		558
Other current liabilities		1,031		363
Accrued license obligations		56		213
Total	$	3,453	$	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 tables includes a roll forward of the restructuring activity and payments recorded for the three and nine months ended September 30, 2024 (in thousands):

	*Severance and Benefits Costs*
Balance at June 30, 2024	$	2,850
Adjustments to restructuring charges	$	183
Cash payments		(805	)
Balance at September 30, 2024	$	2,228

	*Severance and Benefits Costs*
Balance at December 31, 2023	$	5,105
Adjustments to restructuring charges	$	(86	)
Cash payments		(2,791	)
Balance at September 30, 2024	$	2,228

Note 3 - Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Total revenue	$ 0	$ 19,520	$ 53	$ 41,511
Pfizer [Member]
Total revenue	0	9,179	6	14,088
Astra Zeneca A B [Member]
Total revenue	0	3,909	0	8,399
Les Laboratoires Servier And Institut De Recherches Internationales Servier [Member]
Total revenue	0	3,951	47	3,846
Genentech [Member]
Total revenue	0	0	0	12,697
Boston Pharmaceuticals [Member]
Total revenue	$ 0	$ 2,481	$ 0	$ 2,481

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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Note 1 - Corporate Information (Details Textual) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
	Jul. 18, 2023	Sep. 30, 2024 USD ($) $ / shares	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) $ / shares	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($) $ / shares	Aug. 07, 2024 $ / shares	Mar. 27, 2024 USD ($)	May 31, 2013
Preferred Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares		$ 0.001		$ 0.001		$ 0.001
Cash, Cash Equivalents, and Short-Term Investments		$ 19,400		$ 19,400
Net Income (Loss) Attributable to Parent		(2,887)	$ (10,752)	(11,369)	$ (19,959)
Retained Earnings (Accumulated Deficit)		(326,333)		(326,333)		$ (314,964)
Series F Preferred Stock [Member]
Preferred Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares							$ 0.01
Preferred Stock, Voting Rights, Number of Votes Per Share							25,000,000
Series F Preferred Stock [Member] \| Board of Directors Chairman [Member]
Preferred Stock, Par or Stated Value Per Share (in dollars per share) \| $ / shares							$ 0.001
Shares Issued, Price Per Share (in dollars per share) \| $ / shares							$ 1
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								$ 15,000
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								$ 40,000
Severance and Benefits Costs [Member]
Restructuring and Related Cost, Number of Positions Eliminated, Period Percent	70.00%
Restructuring and Related Cost, Cost Incurred to Date						7,500
Severance Costs						$ 2,400
Restructuring and Related Cost, Expected Cost Remaining		$ 4,300		$ 4,300
Pieris Pharmaceuticals GmbH [Member]
Business Acquisition, Percentage of Voting Interests Acquired									100.00%

Note 2 - Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2024

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, 2023. There have been no material additions to the significant accounting policies for the nine months ended September 30, 2024.

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, 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.

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, 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 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 historically consisted 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. As of the period ended September 30, 2024, the Company did not have any property and equipment recorded on the condensed consolidated balance sheet.

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 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 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 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 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.

Recent Accounting Pronouncements Not Yet Adopted

In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280), Improvements to Reportable Segment Disclosures, that requires a public entity to disclose significant segment expenses and other segment items on an annual and interim basis and provide in interim periods all disclosures about a reportable segment’s profit or loss and assets that are currently required annually. It requires a public entity to also disclose the title and position of the Chief Operating Decision Maker. The ASU will be effective for all entities for fiscal years beginning after December 15, 2023, and for interim periods within fiscal years beginning after December 15, 2024. The amendments should be applied retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the effect on the condensed consolidated financial statements.

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 condensed consolidated financial statements.

Note 11 - Merger Agreement with Palvella Therapeutics, Inc. (Details Textual)	Jul. 23, 2024 USD ($) $ / shares shares	Sep. 30, 2024 USD ($)
Pre-funded Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares) \| shares	2,592,585
Class of Warrant or Right, Exercise Price, Subtracted Amount From Purchase Price, Per Share	$ 0.001
Class of Warrant or Right, Maximum Beneficial Percentage Ownership If Exercised	4.99%
Class of Warrant or Right, Maximum Percentage of Shares Outstanding if Exercised	9.99%
Class of Warrant or Right, Maximum Percentage Beneficial Ownership With Notice	19.99%
Securities Purchase Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares) \| shares	3,154,241
Shares Issued, Price Per Share (in dollars per share) \| $ / shares	$ 13.7299
Shares Issued, Price Per Share, Multiplier	0.315478
Proceeds from Issuance or Sale of Equity	$ 78,900,000
Palvella [Member]
Contingency, Termination Fee Payable		$ 1,000,000
Contingency, Termination Fee, Receivable		$ 2,000,000
Pieris Pharmaceutical Stockholders [Member]
Ownership Percentage		18.00%
Pavella Stockholders [Member]
Ownership Percentage		82.00%
Palvella Merger [Member]
Merger, Cash Threshold	11,000,000
Palvella Merger [Member] \| Palvella [Member]
Company Valuation	95,000,000
Palvella Merger [Member] \| Pieris Pharmaceutical Stockholders [Member]
Company Valuation	$ 21,000,000

Note 6 - Assets Held for Sale (Details Textual) $ in Millions	9 Months Ended
	Sep. 30, 2024 USD ($)
Gain (Loss) on Disposition of Assets	$ 0.2

Note 10 - Leases (Details Textual) $ in Thousands, € in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 EUR (€)	Feb. 29, 2020 ft²
Operating Lease, Payments \| $	$ 0	$ 500	$ 0	$ 1,600
Office and Laboratory Space [Member] \| Hallbergmoos Germany [Member]
Lessee, Operating Lease, Term of Contract (Year)						12 years 6 months
Area of Real Estate Property (Square Foot) \| ft²						105,000
Termination Fee \| €					€ 9.7

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

Note 5 - Cash, Cash Equivalents and Investments

9 Months Ended

Sep. 30, 2024

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

5. Cash, cash equivalents and investments

As of September 30, 2024 and December 31, 2023, cash, cash equivalents and investments comprised funds in depository, money market funds 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 September 30, 2024 and December 31, 2023.

	*Total*		*Quoted prices in active markets (Level 1)*		*Significant other observable inputs (Level 2)*		*Significant unobservable inputs (Level 3)*
September 30, 2024
Money market funds, included in cash equivalents	$	11,893	$	11,893	$	—	$	—
Total	$	11,893	$	11,893	$	—	$	—

	*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 September 30, 2024.

The Company recorded no realized gains or losses from the maturity of available-for-sale securities during the three and nine months ended September 30, 2024 and 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.

Note 3 - Revenue - Potential Milestone Payments Received (Details) - Collaborative Arrangement [Member] $ in Millions	Sep. 30, 2024 USD ($)
Research And Development Milestone Payments [Member]
milestone	$ 844
Research And Development Milestone Payments [Member] \| Pfizer [Member]
milestone	759
Research And Development Milestone Payments [Member] \| Boston Pharmaceuticals [Member]
milestone	85
Sales Milestone Payments [Member]
milestone	715
Sales Milestone Payments [Member] \| Pfizer [Member]
milestone	450
Sales Milestone Payments [Member] \| Boston Pharmaceuticals [Member]
milestone	$ 265

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

9 Months Ended

Sep. 30, 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)*
September 30, 2024
Money market funds, included in cash equivalents	$	11,893	$	11,893	$	—	$	—
Total	$	11,893	$	11,893	$	—	$	—

	*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 Operations and Comprehensive Loss (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenue
Customer revenue	$ 0	$ 15,569	$ 6	$ 37,665
Collaboration revenue	0	3,951	47	3,846
Total revenue	0	19,520	53	41,511
Operating expenses
Research and development	(446)	9,595	1,523	37,347
General and administrative	3,581	6,839	11,145	14,526
Asset impairment	0	14,893	0	14,893
Total operating expenses	3,135	31,327	12,668	66,766
Loss from operations	(3,135)	(11,807)	(12,615)	(25,255)
Other income
Interest income	169	549	610	1,396
Grant income	0	0	0	3,612
Other income	79	506	636	288
Net loss	(2,887)	(10,752)	(11,369)	(19,959)
Other comprehensive income loss:
Foreign currency translation	120	(204)	(343)	(159)
Unrealized gain (loss) on available-for-sale securities	0	2	(1)	74
Comprehensive loss	$ (2,767)	$ (10,954)	$ (11,713)	$ (20,044)
Net loss per share
Basic (in dollars per share)	$ (2.19)	$ (8.7)	$ (8.84)	$ (18.33)
Diluted (in dollars per share)	$ (2.19)	$ (8.7)	$ (8.84)	$ (18.33)
Weighted average number of common shares outstanding
Basic (in shares)	1,320	1,236	1,285	1,089
Diluted (in shares)	1,320	1,236	1,285	1,089

Condensed Consolidated Statements of Changes in Stockholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	At the Market Offering [Member] Preferred Stock [Member]	At the Market Offering [Member] Common Stock [Member]	At the Market Offering [Member] Additional Paid-in Capital [Member]	At the Market Offering [Member] AOCI Attributable to Parent [Member]	At the Market Offering [Member] Retained Earnings [Member]	At the Market Offering [Member]	Preferred Stock [Member]	Common Stock [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	$ 318,603	$ (254)	$ (290,421)	$ 27,929
Net loss							0	0	0	0	(19,959)	(19,959)
Stock based compensation expense							0	0	2,898	0	0	2,898
Foreign currency translation adjustment							0	0	0	(159)	0	(159)
Unrealized gain on investments							$ 0	$ 0	0	74	0	74
Balance (in shares) at Sep. 30, 2023							16	1,236
Balance at Sep. 30, 2023							$ 0	$ 1	341,228	(339)	(310,380)	30,510
Issuance of common stock resulting from purchase of employee stock purchase plan shares (in shares)							0	1
Issuance of common stock resulting from purchase of employee stock purchase plan shares							$ 0	$ 0	52	0	0	52
Issuance of common stock pursuant to ATM offering program, net of $0.7 million in offering costs (in shares)	0	303
Issuance of common stock pursuant to ATM offering program, net of $0.7 million in offering costs	$ 0	$ 0	$ 19,675	$ 0	$ 0	$ 19,675
Unrealized gain on investments							$ 0	$ 0	0	74	0	74
Balance (in shares) at Jun. 30, 2023							16	1,236
Balance at Jun. 30, 2023							$ 0	$ 1	340,262	(137)	(299,628)	40,498
Net loss							0	0	0	0	(10,752)	(10,752)
Stock based compensation expense							0	0	966	0	0	966
Foreign currency translation adjustment							0	0	0	(204)	0	(204)
Unrealized gain on investments							$ 0	$ 0	0	2	0	2
Balance (in shares) at Sep. 30, 2023							16	1,236
Balance at Sep. 30, 2023							$ 0	$ 1	341,228	(339)	(310,380)	30,510
Unrealized gain on investments							$ 0	$ 0	0	2	0	2
Balance (in shares) at Dec. 31, 2023							16	1,237
Balance at Dec. 31, 2023							$ 0	$ 1	341,693	28	(314,964)	26,758
Net loss							0	0	0	0	(11,369)	(11,369)
Stock based compensation expense							0	0	1,223	0	0	1,223
Foreign currency translation adjustment							0	0	0	(343)	0	(343)
Unrealized gain on investments							$ 0	$ 0	0	(1)	0	(1)
Balance (in shares) at Sep. 30, 2024							16	1,320
Balance at Sep. 30, 2024							$ 0	$ 1	342,916	(316)	(326,333)	16,268
Unrealized gain on investments							$ 0	$ 0	0	(1)	0	(1)
Round-Up shares from the 1-for-80 reverse split effective April 23, 2024 (in shares)							0	83
Balance (in shares) at Jun. 30, 2024							16	1,320
Balance at Jun. 30, 2024							$ 0	$ 1	342,586	(436)	(323,446)	18,705
Net loss							0	0	0	0	(2,887)	(2,887)
Stock based compensation expense							0	0	330	0	0	330
Foreign currency translation adjustment							$ 0	$ 0	0	120	0	120
Balance (in shares) at Sep. 30, 2024							16	1,320
Balance at Sep. 30, 2024							$ 0	$ 1	$ 342,916	$ (316)	$ (326,333)	$ 16,268

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

Note 7 - Accrued Expenses - Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Compensation expense	$ 2,306	$ 6,448
Research and development fees	0	968
Accrued accounts payable	60	558
Other current liabilities	1,031	363
Accrued license obligations	56	213
Total	$ 3,453	$ 8,550

Document And Entity Information - shares	9 Months Ended
Document And Entity Information - shares	Sep. 30, 2024	Nov. 13, 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	Q3
Document Fiscal Year Focus	2024
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 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

Significant Accounting Policies (Policies)

9 Months Ended

Sep. 30, 2024

Accounting Policies [Abstract]

Basis of Accounting, 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

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

Impairment of Long-lived Assets

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 Not Yet Adopted

Note 9 - Stockholders' Equity

9 Months Ended

Sep. 30, 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 1,320,240 shares and 1,236,688 shares of common stock issued and outstanding as of September 30, 2024 and December 31, 2023, respectively, with a par value of $0.001 per share.

The Company had 10,000,000 shares authorized, 15,618 shares of preferred stock issued and outstanding as of September 30, 2024 and 15,618 shares of preferred stock issued and outstanding as of December 31, 2023. Preferred stock has a par value of $0.001 per share, and the Series A-E convertible preferred stock 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 September 30, 2024 and December 31, 2023, respectively.

•

Series B Convertible, 4,026 shares issued and outstanding at September 30, 2024 and December 31, 2023, respectively.

•

Series C Convertible, 3,506 shares issued and outstanding at September 30, 2024 and December 31, 2023, respectively.

•

Series D Convertible, 3,000 shares issued and outstanding at September 30, 2024 and December 31, 2023, respectively.

•

Series E Convertible, 5,000 shares issued and outstanding at September 30, 2024 and December 31, 2023, respectively.

•

Series F Preferred, 1 share issued and outstanding at September 30, 2024, and no shares issued and outstanding at December 31, 2023

Subscription and Investment Representation Agreement (Series F Preferred Stock)

On August 7, 2024, the Company entered into a Subscription and Investment Representation Agreement with the Purchaser, pursuant to which the Company agreed to issue and sell one ( 1) share of the Company’s Series F Preferred Stock, par value $0.001 per share, to the Purchaser for $1.00 cash. The sale closed on August 7, 2024.

Voting Rights

The Series F Preferred Stock have no voting rights other than the right to vote on the Authorized Share Increase Proposal . Each share of Series F Preferred Stock outstanding on the record date entitles the holder thereof to 25,000,000 votes on Authorized Share Increase Proposal, and all shares of Series F Preferred Stock held by such holder must and will be voted, without further action by such holder, in the same proportion as the aggregate shares of Pieris common stock (excluding any shares of Pieris common stock that are not voted) that are voted on the Authorized Share Increase Proposal. As an example, if 70% of the aggregate votes cast by Pieris common stock voting on the Authorized Share Increase Proposal are voted in favor thereof and 30% of the aggregate votes cast by Pieris common stock voting on the Authorized Share Increase Proposal are voted against such Proposal, then 70% of the votes entitled to be cast by the Series F Preferred Stock will be cast in favor of the Proposal and 30% of such votes will be cast against the Proposal. For purposes of the foregoing, abstentions and broker non-votes will not be considered votes cast.

Conversion and Redemption

Shares of the Series F Preferred Stock are not convertible into any other security, and are redeemable by the Company upon the earlier to occur of: (i) the order of the Pieris board of directors in its sole discretion, automatically and effective at such date and time as is determined and specified by the Pieris board of directors in its sole discretion and (ii) automatically and effective immediately after the effectiveness of the increase in the number of authorized shares of Pieris common stock proposed in the Authorized Share Increase Proposal. Upon redemption, the holder of the Series F Preferred Stock will receive cash consideration of $0.01 per share. Shares of the Series F Preferred Stock may not be transferred prior to their redemption without the prior written consent of the Pieris board of directors.

Other Rights and Restrictions

Each holder of Series F Preferred Stock has entered into a written agreement with the Company to attend the Pieris special meeting, to vote all shares of Series F Preferred Stock with regard to the Authorized Share Increase Proposal in the same proportion as the aggregate shares of Pieris common stock (excluding any shares of Pieris common stock that are not voted) are voted on the Authorized Share Increase Proposal and, upon request by the Company, to grant a designee of the Company an irrevocable proxy to vote the shares of Series F Preferred Stock in accordance with the foregoing.

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. As of September 30, 2024, there are 333,145 shares remaining and available for grant 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 nine months ended September 30, 2024, the Company did not sell any shares under the ATM Program. 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.

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 6 - Assets Held for Sale (Tables)

9 Months Ended

Sep. 30, 2024

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

	*September 30,*		*December 31,*
	*2024*		*2023*
Laboratory furniture and equipment	$	—	$	1,967
Office furniture and equipment		—		221
Assets held for sale	$	—	$	2,188

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

Note 6 - Assets Held for Sale - Summary of Assets Held for Sale (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Assets held for sale	$ 0	$ 2,188
Laboratory Furniture and Equipment [Member]
Assets held for sale	0	1,967
Office Furniture and Equipment [Member]
Assets held for sale	$ 0	$ 221

Note 5 - Cash, Cash Equivalents and Investments (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Debt Securities, Available-for-Sale, Realized Gain (Loss)	$ 0	$ 0	$ 0	$ (100)

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 19,363	$ 17,396
Short term investments	0	8,970
Accounts receivable	373	572
Receivable from public grants	0	3,141
Other receivables	506	2,326
Assets held for sale, property and equipment	0	2,188
Prepaid expenses and other current assets	280	4,087
Total current assets	20,522	38,680
Current liabilities:
Accounts payable	801	3,372
Accrued expenses and other current liabilities	3,453	8,550
Total current liabilities	4,254	11,922
Stockholders’ equity:
Preferred stock	0	0
Common stock	1	1
Additional paid-in capital	342,916	341,693
Accumulated other comprehensive income (loss)	(316)	28
Accumulated deficit	(326,333)	(314,964)
Total stockholders’ equity	16,268	26,758
Total liabilities and stockholders’ equity	$ 20,522	$ 38,680

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

3 Months Ended

9 Months Ended

Sep. 30, 2024

Sep. 30, 2023

Sep. 30, 2024

Sep. 30, 2023

Operating lease costs

$ 0

$ 280

$ 0

$ 862

Variable lease costs (1)

^[1]

476

Total lease cost

$ 0

$ 378

$ 0

$ 1,338

[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.

Note 7 - Accrued Expenses - Restructuring Activity (Details) - Severance and Benefits Costs [Member] - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Balance	$ 2,850	$ 5,105
Adjustments to restructuring charges	183	(86)
Cash payments	(805)	(2,791)
Balance	$ 2,228	$ 2,228

Note 6 - Assets Held for Sale

9 Months Ended

Sep. 30, 2024

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

6. Assets Held for Sale

As of September 30, 2024 and December 31, 2023, assets held for sale are summarized as follows (in thousands):

	*September 30,*		*December 31,*
	*2024*		*2023*
Laboratory furniture and equipment	$	—	$	1,967
Office furniture and equipment		—		221
Assets held for sale	$	—	$	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, as of December 31, 2023 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 nine months ended September 30, 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 recovered the total net book value of the assets held for sale and recorded a gain on the sale of the assets of $0.2 million within "Other income (loss)" in the accompanying condensed consolidated statements of operations and comprehensive loss for the nine months ended September 30, 2024.

Note 10 - Leases (Tables)

9 Months Ended

Sep. 30, 2024

Lease, Cost [Table Text Block]

	*Three Months Ended September 30,*				*Nine Months Ended September 30,*
	*2024*		*2023*		*2024*		*2023*
Operating lease costs	$	—	$	280	$	—	$	862
Variable lease costs (1)		—		98		—		476
Total lease cost	$	—	$	378	$	—	$	1,338

Note 8 - Net Loss Per Share (Details Textual) - $ / shares shares in Millions	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	0.5	0.5
2019 Private Placement Financing [Member]
Class of Warrant or Right, Outstanding (in shares)	0.1
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 568
Warrants and Rights Outstanding, Term (Year)	5 years

Note 8 - Net Loss Per Share - Schedule of Reconciliation of Basic and Diluted Income per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Net Income (Loss) Attributable to Parent	$ (2,887)	$ (10,752)	$ (11,369)	$ (19,959)
Basic weighted average common shares outstanding (in shares)	1,320	1,236	1,285	1,089
Diluted weighted average common shares outstanding (in shares)	1,320	1,236	1,285	1,089
Basic net loss per share (in dollars per share)	$ (2.19)	$ (8.7)	$ (8.84)	$ (18.33)
Diluted net loss per share (in dollars per share)	$ (2.19)	$ (8.7)	$ (8.84)	$ (18.33)

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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

9 Months Ended

Sep. 30, 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 Ismaning, 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 continuing through September 30, 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.

Approximately $2.4 million of the termination benefits were paid in 2023. The Company expects approximately $4.3 million of the termination benefits to be paid through the end of 2024, with the remainder of termination benefits to be paid in 2025.

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 $15.0 million upon first patient dosed in the Phase 2 trials for SGN-BB228 and BOS-342, which are currently in Phase 1 clinical development, and up to approximately $40.0 million upon first patient dosed in pivotal clinical trials for SGN-BB228 and BOS-342.

On July 23, 2024, the Company and its wholly-owned subsidiary, Polo Merger Sub, Inc., or Merger Sub, entered into an Agreement and Plan of Merger (the “Merger Agreement”) with Palvella Therapeutics, Inc., or Palvella, discussed further in Note 11, whereby Merger Sub will merge with and into Palvella, with Palvella continuing as a wholly-owned subsidiary of the Company and the surviving corporation of the merger, or the Merger. Subject to the terms and conditions of the Merger Agreement, at the effective time of the Merger, (i) each then-outstanding share of Palvella capital stock will be converted into the right to receive a number of shares of the Company's common stock equal to the Exchange Ratio as defined in the Merger Agreement; and (ii) each then-outstanding Palvella stock option to purchase Palvella common stock will be assumed by the Company. Each of the Company and Palvella has agreed to customary representations, warranties and covenants in the Merger Agreement, including, among others, covenants relating to (1) using reasonable best efforts to obtain the requisite approvals of their respective stockholders, (2) non-solicitation of alternative acquisition proposals, (3) the conduct of their respective businesses during the period between the date of signing the Merger Agreement and the closing of the Merger, (4) the Company using its commercially reasonable efforts to maintain the existing listing of the Company's common stock on Nasdaq and the Company causing the shares of the Company's common stock to be issued in connection with the Merger to be approved for listing on Nasdaq prior to the closing of the Merger and (5) the Company filing with the U.S. Securities and Exchange Commission, or the SEC, and causing to become effective a registration statement to register the shares of the Company's common stock to be issued in connection with the Merger.

On August 7, 2024, the Company entered into a Subscription and Investment Representation Agreement with James Geraghty, Chairman of the Company’s Board of Directors, or the Purchaser, pursuant to which the Company agreed to issue and sell one (1) share of the Company’s Series F Preferred Stock, par value $0.001 per share, to the Purchaser for $1.00 cash. The sale closed on August 7, 2024. The Series F Preferred Stock have no voting rights other than the right to vote on a proposed amendment to the Company’s amended and restated articles of incorporation to effect an increase in the number of authorized shares of the Company’s common stock, or the Authorized Share Increase Proposal. Each share of Series F Preferred Stock outstanding on the record date entitles the holder thereof to 25,000,000 votes on the Authorized Share Increase Proposal, and all shares of Series F Preferred Stock held by such holder must and will be voted, without further action by such holder, in the same proportion as the aggregate shares of Pieris common stock (excluding any shares of Pieris common stock that are not voted) that are voted on the Authorized Share Increase Proposal.

As of September 30, 2024, cash and cash equivalents were $19.4 million. For the three months ended September 30, 2024 and 2023, the Company had a net loss of $2.9 million and $10.8 million, respectively. For the nine months ended September 30, 2024 and 2023, the Company had net losses of $11.4 million and $20.0 million, respectively. The Company has incurred net losses since inception and had an accumulated deficit of $326.3 million as of September 30, 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 previous decision to implement measures to maximize its ability to capture potential milestones from its partnered programs with Pfizer and Boston Pharmaceuticals (all as defined in Note 3 below) and the Company's plan to consummate the potential Merger, subject to stockholder approval, the Company has discontinued all research and development efforts and continues to 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.

Note 8 - Net Loss Per Share (Tables)

9 Months Ended

Sep. 30, 2024

Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]

	*Three Months Ended September 30,*						*Nine Months Ended September 30,*
	*2024*			*2023*			*2024*			*2023*
Net loss	$	(2,887	)	$	(10,752	)	$	(11,369	)	$	(19,959	)
Basic weighted average common shares outstanding		1,320			1,236			1,285			1,089
Diluted weighted average common shares outstanding		1,320			1,236			1,285			1,089
Basic net loss per share	$	(2.19	)	$	(8.70	)	$	(8.84	)	$	(18.33	)
Diluted net loss per share	$	(2.19	)	$	(8.70	)	$	(8.84	)	$	(18.33	)

Insider Trading Arrangements	3 Months Ended	9 Months Ended
Insider Trading Arrangements	Sep. 30, 2024	Sep. 30, 2024
Insider Trading Arr Line Items
Material Terms of Trading Arrangement [Text Block]		Item 5. Other Information. None.
Rule 10b5-1 Arrangement Adopted [Flag]	false
Non-Rule 10b5-1 Arrangement Adopted [Flag]	false
Rule 10b5-1 Arrangement Terminated [Flag]	false
Non-Rule 10b5-1 Arrangement Terminated [Flag]	false

Note 3 - Revenue (Details Textual) $ in Thousands	1 Months Ended		3 Months Ended			9 Months Ended		12 Months Ended
Note 3 - Revenue (Details Textual) $ in Thousands	Aug. 31, 2023 USD ($)	Jan. 31, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2017	May 19, 2021 USD ($)	Feb. 08, 2018	May 02, 2017
Increase in Contract With Customer Liability			$ 0			$ 0
Decrease in Contract with Customer, Liability			$ 0	$ 17,100		$ 0	$ 38,700
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			$ 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

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

Note 3 - Revenue

9 Months Ended

Sep. 30, 2024

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 September 30,*				*Nine Months Ended September 30,*
	*2024*		*2023*		*2024*		*2023*
Pfizer (formerly Seagen)	$	—	$	9,179	$	6	$	14,088
AstraZeneca		—		3,909		—		8,399
Servier		—		3,951		47		3,846
Genentech		—		—		—		12,697
Boston Pharmaceuticals		—		2,481		—		2,481
Total Revenue	$	—	$	19,520	$	53	$	41,511

As of September 30, 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 (formerly Seagen)	$	759	$	450
Boston Pharmaceuticals		85		265
Total potential milestone payments	$	844	$	715

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 also had options to select two additional programs with the payment of a fee, which expired in May 2024. With the expiration of these options and no programs active or ongoing, the Genentech Agreement also expired.

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® (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 Agreement, 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 as PRS- 344, a 4- 1BB/PD- L1 bispecific Mabcalin protein, in the United States. 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.

On June 28, 2024, Servier provided the Company with a written notice of termination of the Servier Collaboration Agreement. Pursuant to the Servier Platform License Agreement, the Servier Platform License Agreement terminates upon termination of the Servier Collaboration Agreement. The Servier Collaboration Agreement and Servier Platform License Agreements will terminate effective December 27, 2024, or 180 days from the date on which Servier notified the Company of its intent to terminate both agreements.

With this notice, Servier will discontinue and cease dosing in the Phase 1 clinical study of S095012. Servier's decision to terminate both agreements was based on a potential safety concern in S095012 Phase 1 clinical studies. The Company does not intend to pursue any further development of S095012.

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, 2024. There were no reductions to deferred revenue for the three and nine months ended September 30, 2024 and 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.

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Note 10 - Leases

9 Months Ended

Sep. 30, 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 Hallbergmoos 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 and nine months ended September 30, 2024. Cash paid for amounts included in the measurement of the lease liabilities was $0.5 million and $1.6 million for the three and nine months ended September 30, 2023, respectively.

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

	*Three Months Ended September 30,*				*Nine Months Ended September 30,*
	*2024*		*2023*		*2024*		*2023*
Operating lease costs	$	—	$	280	$	—	$	862
Variable lease costs (1)		—		98		—		476
Total lease cost	$	—	$	378	$	—	$	1,338

(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.

Note 4 - Grant Income

9 Months Ended

Sep. 30, 2024