0000950170-24-127019 | 10-Q | XBRL Viewer

Goodwill and Indefinite-Lived Intangible Assets	9 Months Ended
Sep. 30, 2024
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Indefinite-Lived Intangible Assets	6. Goodwill and Indefinite-Lived Intangible Assets $6,330 of goodwill and $79,200 of indefinite-lived intangible assets acquired in the Lung Acquisition were recorded at fair value on the Lung Acquisition date. The Company performed a qualitative assessment of goodwill and indefinite-lived intangible assets for potential impairment as of September 30, 2024, and concluded that there was no goodwill or intangible assets impairment as of September 30, 2024.

Goodwill and Indefinite-Lived Intangible Assets

9 Months Ended

Sep. 30, 2024

Goodwill and Intangible Assets Disclosure [Abstract]

Goodwill and Indefinite-Lived Intangible Assets

6. Goodwill and Indefinite-Lived Intangible Assets

$6,330 of goodwill and $79,200 of indefinite-lived intangible assets acquired in the Lung Acquisition were recorded at fair value on the Lung Acquisition date. The Company performed a qualitative assessment of goodwill and indefinite-lived intangible assets for potential impairment as of September 30, 2024, and concluded that there was no goodwill or intangible assets impairment as of September 30, 2024.

Commitments and Contingencies	9 Months Ended
Sep. 30, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	15. Commitments and Contingencies Operating Leases On August 16, 2021, Lung entered into an operating lease agreement to rent approximately 6,455 square feet of office space for its corporate headquarters in Austin, Texas, beginning on October 1, 2021. The lease expired March 31, 2024, and the Company did not renew the lease. Following expiration of the lease, the Company is operating virtually, and expects to do so for the foreseeable future. Legal Proceedings The Company may from time to time be party to litigation arising in the ordinary course of business. As of September 30, 2024, the Company was not party to any legal proceedings and no material legal proceedings are currently pending or, to the best of the Company’s knowledge, threatened. Intellectual Property Licenses Harvard and Dana-Farber Agreement In August 2006, the Company entered into an exclusive license agreement with President and Fellows of Harvard College (“Harvard”) and Dana-Farber Cancer Institute (“DFCI”). The agreement granted the Company an exclusive worldwide license, with the right to sublicense, under specified patents and patent applications to develop, obtain regulatory approval for and commercialize specified product candidates based on cell-permeating peptides. Under the agreement, the Company is obligated to use commercially reasonable efforts to develop and commercialize one or more licensed products and to achieve specified milestone events by specified dates. In connection with entering into the agreement, the Company paid an upfront license fee and issued to Harvard and DFCI shares of its common stock. In February 2010, the agreement was amended and restated (the “Harvard/DFCI agreement”) under which additional patent rights were added to the scope of the license agreement and the annual license maintenance fees were increased. Under the Harvard/DFCI agreement, the Company is obligated to make aggregate milestones payments of up to $7,700 per licensed therapeutic product upon the Company’s achievement of specified clinical, regulatory and sales milestones with respect to such product and up to $700 per licensed diagnostic product upon the Company’s achievement of specified regulatory and sales milestones with respect to such product. In addition, the Company is obligated to pay royalties of low single-digit percentages on annual net sales of licensed products sold by the Company, its affiliates or its sublicensees. The royalties are payable on a product-by-product and country-by-country basis and may be reduced in specified circumstances. In addition, the agreement obligates the Company to pay a percentage, up to the mid-twenties, of fees received by the Company in connection with its sublicense of the licensed products. In accordance with the terms of the agreement, the Company’s sublicense payment obligations may be subject to specified reductions. The Harvard/DFCI agreement requires the Company to pay annual license maintenance fees of $110 each year, which was reduced to $35 starting in 2023. Any payments made in connection with the annual license maintenance fees will be credited against any royalties due. As of September 30, 2024, the Company had not developed a commercial product using the licensed technologies and no royalties under the agreement had been paid or were due. Under the Harvard/DFCI agreement, the Company is responsible for all patent expenses related to the prosecution and maintenance of the licensed patents and applications in-licensed under the agreement as well as cost reimbursement of amounts incurred for all documented patent-related expenses. The agreement will expire on a product-by-product and country-by-country basis upon the last to expire of any valid patent claim pertaining to licensed products covered under the agreement. The Company incurred $27 in license maintenance fees in the nine months ended September 30, 2024. No license maintenance fees were incurred by the Company in the nine months ended September 30, 2023. Agreement with the University of Texas Health Science Center at Tyler In June 2013, Lung entered into a patent and technology license agreement with UT System, on behalf of UTHSCT. The patent and technology license agreement with UT System (the “UTHSCT Agreement”) provides Lung access to patents and technology related to the development of LTI-01 and LTI-03. As part of the UTHSCT Agreement, Lung has (i) a royalty-bearing, exclusive license under the patent rights to manufacture, distribute, and sell certain intellectual property; (ii) a non-exclusive license under the technology rights to manufacture, distribute and sell the licensed product; and (iii) a sublicensing right that allows Lung to grant sublicenses to affiliates and third parties to use the licensed product in the field of use and approved territories outlined in the UTHSCT Agreement. In December 2013, the UTHSCT Agreement was amended and restated to include certain patents in all fields worldwide. In May 2017, the UTHSCT Agreement was amended and restated to modify the specific milestone criteria. In consideration of the UTHSCT Agreement, Lung granted UT System (via UTHSCT and UT Horizon Fund affiliates) (i) 2,000,000 shares of Lung common stock and (ii) 400,000 shares of Lung non-convertible preferred stock. On February 6, 2015, UT System exchanged the 400,000 shares of Lung non-convertible preferred stock for 4,000,000 shares of Lung common stock. In addition, Lung agreed to pay past and ongoing patent expenses, and Lung owes UTHSCT sublicensing fees, assignment fees, and single digit royalties on worldwide net product sales, with fixed minimum royalty payments that started in 2015. Pursuant to the UTHSCT Agreement, Lung is required to use diligent efforts to commercialize the licensed technology as soon as commercially practicable, including maintaining active research and development, regulatory, marketing and sales program, all as commercially reasonable. The Company may terminate the UTHSCT Agreement for convenience with 90 days’ notice. UTHSCT may also terminate the UTHSCT Agreement, but only if the Company breaches the terms of the agreement. The Company did not incur any expenses under the UTHSCT Agreement in the nine months ended September 30, 2024 and 2023. Agreement with the University of Texas at Austin In May 2015, Lung entered into a patent license agreement with UT Austin on behalf of UT System. This license agreement with UT Austin (the “UT Austin 6607 Agreement”) relates to the patent rights to polypeptide therapeutics and uses thereof. Pursuant to the UT Austin 6607 Agreement Lung has (i) a royalty-bearing, exclusive license under the patent rights to manufacture, distribute, and sell the licensed product; and (ii) a sublicensing right that allows Lung to grant sublicenses to affiliates and third parties to use the licensed product in the field of use and approved territories outlined in the agreement. The UT Austin 6607 Agreement was amended and restated in January 2017, November 2018, and June 2019. The amendments related to extension of milestone payment dates and specific terminology around the milestone achievement criteria. In consideration of the UT Austin 6607 Agreement, Lung agreed to pay past and ongoing patent expenses, milestone fees upon certain development and regulatory milestone events, annual license fees, tiered sublicense fees, assignment fees, low single digit royalties on net sales and a Food and Drug Administration (“FDA”) Priority Review Voucher fee if Lung sells or transfers this voucher. Pursuant to the UT Austin 6607 Agreement, Lung is required to use diligent efforts to commercialize the licensed products, including maintaining active research and development, regulatory, marketing and sales program. Moreover, Lung is required to meet certain development and regulatory milestones by specific dates. The Company may terminate the UT Austin 6607 Agreement for convenience with 90 days’ notice. UT Austin may also terminate the UT Austin 6607 Agreement, but only if the Company breaches the terms of the agreement. The Company did not incur any expenses under the UT Austin 6607 Agreement in the nine months ended September 30, 2024 and 2023. Agreement with Medical University of South Carolina In March 2016, Lung entered into a license agreement with Medical University of South Carolina Foundation for Research Development (“MUSC”). Pursuant to this license agreement with MUSC (the “MUSC Agreement”) Lung has patent rights related to protecting against lung fibrosis by up regulating Cav1. The MUSC Agreement granted (i) a royalty-bearing, exclusive license under the patent rights to make, use and sell the license product; and (ii) a sublicensing right that allows Lung to grant sublicenses to affiliates and third parties to use the licensed product in the field of use and approved territories outlined in the agreement. In September 2018, the agreement was amended and restated to include definitions of related methods, related products and related rights. In consideration of the MUSC Agreement, Lung agreed to pay a non-refundable license fee, patent expenses, milestone fees upon certain development, regulatory and commercial milestone events, sublicense fees, assignment fees and low single digit royalties on net sales, with a fixed minimum royalty payment starting in 2019 and a transaction fee upon Lung’s liquidation. Pursuant to the MUSC Agreement, Lung is required to use diligent efforts to develop, manufacture and sell the licensed products. The Company may terminate the MUSC Agreement for convenience by providing a written notice to MUSC effective 90 days following the receipt of notice, and either party may terminate the agreement for a breach of contract. The Company incurred $25 in license fee in the nine months ended September 30, 2024. No license fee was incurred by the Company in the nine months ended September 30, 2023. Agreement with Vivarta Therapeutics LLC In March 2018, Lung entered into a license agreement with Vivarta Therapeutics, LLC, or Vivarta. This license agreement with Vivarta (the “Vivarta Agreement”) relates to intellectual property relating to epithelial sodium channel inhibitors and methods to treat pulmonary disease. Pursuant to the Vivarta Agreement Lung has (i) a royalty-bearing, exclusive license under the intellectual property rights to make, use and sell the licensed product, and (ii) a sublicensing right that allows Lung to grant sublicenses to affiliates and third parties to use the licensed product in the field of use and approved territories outlined in the agreement. In consideration for the Vivarta Agreement, Lung agreed to grant Vivarta a warrant to purchase an aggregate of 75,000 shares of Lung common stock for $0.12 per share, to pay a license fee of $10,000 upon the Vivarta Agreement effective date and $40,000 within 30 days of the receipt of a positive freedom to operate analysis from legal counsel. Lung also agreed to pay patent expenses, milestone fees upon certain development and regulatory milestone events, sublicense fees, assignment fees and low single digit royalties on net sales. Pursuant to the Vivarta Agreement, Lung is required to use diligent efforts to develop, manufacture and sell the licensed products. The Company may terminate the Vivarta Agreement for convenience by providing a written notice to Vivarta effective 90 days following the receipt of notice, and either party may terminate the agreement for a breach of contract. The Company did not incur any expenses under the Vivarta Agreement in the nine months ended September 30, 2024 and 2023. Indemnification Agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company does not believe that the outcome of any claims under indemnification arrangements will have a material effect on its financial position, results of operations or cash flows, and it had not accrued any liabilities related to such obligations in its consolidated financial statements as of September 30, 2024 or December 31, 2023.

Commitments and Contingencies

9 Months Ended

Sep. 30, 2024

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

15. Commitments and Contingencies

Operating Leases

On August 16, 2021, Lung entered into an operating lease agreement to rent approximately 6,455 square feet of office space for its corporate headquarters in Austin, Texas, beginning on October 1, 2021. The lease expired March 31, 2024, and the Company did not renew the lease. Following expiration of the lease, the Company is operating virtually, and expects to do so for the foreseeable future.

Legal Proceedings

The Company may from time to time be party to litigation arising in the ordinary course of business. As of September 30, 2024, the Company was not party to any legal proceedings and no material legal proceedings are currently pending or, to the best of the Company’s knowledge, threatened.

Intellectual Property Licenses

Harvard and Dana-Farber Agreement

In August 2006, the Company entered into an exclusive license agreement with President and Fellows of Harvard College (“Harvard”) and Dana-Farber Cancer Institute (“DFCI”). The agreement granted the Company an exclusive worldwide license, with the right to sublicense, under specified patents and patent applications to develop, obtain regulatory approval for and commercialize specified product candidates based on cell-permeating peptides. Under the agreement, the Company is obligated to use commercially reasonable efforts to develop and commercialize one or more licensed products and to achieve specified milestone events by specified dates. In connection with entering into the agreement, the Company paid an upfront license fee and issued to Harvard and DFCI shares of its common stock.

In February 2010, the agreement was amended and restated (the “Harvard/DFCI agreement”) under which additional patent rights were added to the scope of the license agreement and the annual license maintenance fees were increased. Under the Harvard/DFCI agreement, the Company is obligated to make aggregate milestones payments of up to $7,700 per licensed therapeutic product upon the Company’s achievement of specified clinical, regulatory and sales milestones with respect to such product and up to $700 per licensed diagnostic product upon the Company’s achievement of specified regulatory and sales milestones with respect to such product. In addition, the Company is obligated to pay royalties of low single-digit percentages on annual net sales of licensed products sold by the Company, its affiliates or its sublicensees. The royalties are payable on a product-by-product and country-by-country basis and may be reduced in specified circumstances. In addition, the agreement obligates the Company to pay a percentage, up to the mid-twenties, of fees received by the Company in connection with its sublicense of the licensed products. In accordance with the terms of the agreement, the Company’s sublicense payment obligations may be subject to specified reductions.

The Harvard/DFCI agreement requires the Company to pay annual license maintenance fees of $110 each year, which was reduced to $35 starting in 2023. Any payments made in connection with the annual license maintenance fees will be credited against any royalties due.

As of September 30, 2024, the Company had not developed a commercial product using the licensed technologies and no royalties under the agreement had been paid or were due.

Under the Harvard/DFCI agreement, the Company is responsible for all patent expenses related to the prosecution and maintenance of the licensed patents and applications in-licensed under the agreement as well as cost reimbursement of amounts incurred for all documented patent-related expenses. The agreement will expire on a product-by-product and country-by-country basis upon the last to expire of any valid patent claim pertaining to licensed products covered under the agreement. The Company incurred $27 in license maintenance fees in the nine months ended September 30, 2024. No license maintenance fees were incurred by the Company in the nine months ended September 30, 2023.

Agreement with the University of Texas Health Science Center at Tyler

In June 2013, Lung entered into a patent and technology license agreement with UT System, on behalf of UTHSCT. The patent and technology license agreement with UT System (the “UTHSCT Agreement”) provides Lung access to patents and technology related to the development of LTI-01 and LTI-03. As part of the UTHSCT Agreement, Lung has (i) a royalty-bearing, exclusive license under the patent rights to manufacture, distribute, and sell certain intellectual property; (ii) a non-exclusive license under the technology rights to manufacture, distribute and sell the licensed product; and (iii) a sublicensing right that allows Lung to grant sublicenses to affiliates and third parties to use the licensed product in the field of use and approved territories outlined in the UTHSCT Agreement. In December

2013, the UTHSCT Agreement was amended and restated to include certain patents in all fields worldwide. In May 2017, the UTHSCT Agreement was amended and restated to modify the specific milestone criteria.

In consideration of the UTHSCT Agreement, Lung granted UT System (via UTHSCT and UT Horizon Fund affiliates) (i) 2,000,000 shares of Lung common stock and (ii) 400,000 shares of Lung non-convertible preferred stock. On February 6, 2015, UT System exchanged the 400,000 shares of Lung non-convertible preferred stock for 4,000,000 shares of Lung common stock. In addition, Lung agreed to pay past and ongoing patent expenses, and Lung owes UTHSCT sublicensing fees, assignment fees, and single digit royalties on worldwide net product sales, with fixed minimum royalty payments that started in 2015.

Pursuant to the UTHSCT Agreement, Lung is required to use diligent efforts to commercialize the licensed technology as soon as commercially practicable, including maintaining active research and development, regulatory, marketing and sales program, all as commercially reasonable.

The Company may terminate the UTHSCT Agreement for convenience with 90 days’ notice. UTHSCT may also terminate the UTHSCT Agreement, but only if the Company breaches the terms of the agreement. The Company did not incur any expenses under the UTHSCT Agreement in the nine months ended September 30, 2024 and 2023.

Agreement with the University of Texas at Austin

In May 2015, Lung entered into a patent license agreement with UT Austin on behalf of UT System. This license agreement with UT Austin (the “UT Austin 6607 Agreement”) relates to the patent rights to polypeptide therapeutics and uses thereof. Pursuant to the UT Austin 6607 Agreement Lung has (i) a royalty-bearing, exclusive license under the patent rights to manufacture, distribute, and sell the licensed product; and (ii) a sublicensing right that allows Lung to grant sublicenses to affiliates and third parties to use the licensed product in the field of use and approved territories outlined in the agreement. The UT Austin 6607 Agreement was amended and restated in January 2017, November 2018, and June 2019. The amendments related to extension of milestone payment dates and specific terminology around the milestone achievement criteria.

In consideration of the UT Austin 6607 Agreement, Lung agreed to pay past and ongoing patent expenses, milestone fees upon certain development and regulatory milestone events, annual license fees, tiered sublicense fees, assignment fees, low single digit royalties on net sales and a Food and Drug Administration (“FDA”) Priority Review Voucher fee if Lung sells or transfers this voucher.

Pursuant to the UT Austin 6607 Agreement, Lung is required to use diligent efforts to commercialize the licensed products, including maintaining active research and development, regulatory, marketing and sales program. Moreover, Lung is required to meet certain development and regulatory milestones by specific dates.

The Company may terminate the UT Austin 6607 Agreement for convenience with 90 days’ notice. UT Austin may also terminate the UT Austin 6607 Agreement, but only if the Company breaches the terms of the agreement. The Company did not incur any expenses under the UT Austin 6607 Agreement in the nine months ended September 30, 2024 and 2023.

Agreement with Medical University of South Carolina

In March 2016, Lung entered into a license agreement with Medical University of South Carolina Foundation for Research Development (“MUSC”). Pursuant to this license agreement with MUSC (the “MUSC Agreement”) Lung has patent rights related to protecting against lung fibrosis by up regulating Cav1. The MUSC Agreement granted (i) a royalty-bearing, exclusive license under the patent rights to make, use and sell the license product; and (ii) a sublicensing right that allows Lung to grant sublicenses to affiliates and third parties to use the licensed product in the field of use and approved territories outlined in the agreement. In September 2018, the agreement was amended and restated to include definitions of related methods, related products and related rights.

In consideration of the MUSC Agreement, Lung agreed to pay a non-refundable license fee, patent expenses, milestone fees upon certain development, regulatory and commercial milestone events, sublicense fees, assignment fees and low single digit royalties on net sales, with a fixed minimum royalty payment starting in 2019 and a transaction fee upon Lung’s liquidation.

Pursuant to the MUSC Agreement, Lung is required to use diligent efforts to develop, manufacture and sell the licensed products.

The Company may terminate the MUSC Agreement for convenience by providing a written notice to MUSC effective 90 days following the receipt of notice, and either party may terminate the agreement for a breach of contract. The Company incurred $25 in license fee in the nine months ended September 30, 2024. No license fee was incurred by the Company in the nine months ended September 30, 2023.

Agreement with Vivarta Therapeutics LLC

In March 2018, Lung entered into a license agreement with Vivarta Therapeutics, LLC, or Vivarta. This license agreement with Vivarta (the “Vivarta Agreement”) relates to intellectual property relating to epithelial sodium channel inhibitors and methods to treat pulmonary disease. Pursuant to the Vivarta Agreement Lung has (i) a royalty-bearing, exclusive license under the intellectual property rights to make, use and sell the licensed product, and (ii) a sublicensing right that allows Lung to grant sublicenses to affiliates and third parties to use the licensed product in the field of use and approved territories outlined in the agreement.

In consideration for the Vivarta Agreement, Lung agreed to grant Vivarta a warrant to purchase an aggregate of 75,000 shares of Lung common stock for $0.12 per share, to pay a license fee of $10,000 upon the Vivarta Agreement effective date and $40,000 within 30 days of the receipt of a positive freedom to operate analysis from legal counsel. Lung also agreed to pay patent expenses, milestone fees upon certain development and regulatory milestone events, sublicense fees, assignment fees and low single digit royalties on net sales.

Pursuant to the Vivarta Agreement, Lung is required to use diligent efforts to develop, manufacture and sell the licensed products.

The Company may terminate the Vivarta Agreement for convenience by providing a written notice to Vivarta effective 90 days following the receipt of notice, and either party may terminate the agreement for a breach of contract. The Company did not incur any expenses under the Vivarta Agreement in the nine months ended September 30, 2024 and 2023.

Indemnification Agreements

In the ordinary course of business, the Company may provide indemnification of varying scope and terms to vendors, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company does not believe that the outcome of any claims under indemnification arrangements will have a material effect on its financial position, results of operations or cash flows, and it had not accrued any liabilities related to such obligations in its consolidated financial statements as of September 30, 2024 or December 31, 2023.

Condensed Consolidated Statement of Changes in Convertible Preferred Stock and Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Series X Non-Voting Convertible Preferred Stock [Member]	Common Stock [Member]	Common Stock [Member] Series X Non-Voting Convertible Preferred Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Series X Non-Voting Convertible Preferred Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
Beginning balance, shares at Dec. 31, 2022			4,541,167
Beginning balance at Dec. 31, 2022	$ 18,623		$ 91		$ 291,365		$ (48)	$ (272,785)
Stock-based compensation expense	391				391
Unrealized gain on investments	38						38
Net loss	(4,779)							(4,779)
Ending balance, shares at Mar. 31, 2023			4,541,167
Ending balance at Mar. 31, 2023	14,273		$ 91		291,756		(10)	(277,564)
Beginning balance, shares at Dec. 31, 2022			4,541,167
Beginning balance at Dec. 31, 2022	$ 18,623		$ 91		291,365		(48)	(272,785)
Exercises of stock options, shares	0
Unrealized gain on investments	$ 48
Net loss	(8,393)
Ending balance, shares at Sep. 30, 2023			4,541,167
Ending balance at Sep. 30, 2023	11,198		$ 91		292,285			(281,178)
Beginning balance, shares at Mar. 31, 2023			4,541,167
Beginning balance at Mar. 31, 2023	14,273		$ 91		291,756		(10)	(277,564)
Stock-based compensation expense	300				300
Unrealized gain on investments	8						8
Net loss	(1,787)							(1,787)
Ending balance, shares at Jun. 30, 2023			4,541,167
Ending balance at Jun. 30, 2023	12,794		$ 91		292,056		(2)	(279,351)
Stock-based compensation expense	229				229
Unrealized gain on investments	2						2
Net loss	(1,827)							(1,827)
Ending balance, shares at Sep. 30, 2023			4,541,167
Ending balance at Sep. 30, 2023	$ 11,198		$ 91		292,285			(281,178)
Beginning balance, shares at Dec. 31, 2023	4,885,512		4,885,512
Beginning balance at Dec. 31, 2023	$ 98,297	$ 91,410	$ 91		295,376		(63)	(288,517)
Beginning balance, shares at Dec. 31, 2023		24,610
Issuance of common stock in connection with conversion of Series X non-voting convertible preferred stock, value		$ (44,826)
Issuance of common stock in connection with conversion of Series X non-voting convertible preferred stock, shares		(11,957)
Issuance of common stock				$ 12		$ 44,814
Issuance of common stock, shares				11,957,000
Stock-based compensation expense	150				150
Net loss	(7,113)							(7,113)
Ending balance, shares at Mar. 31, 2024			16,842,512
Ending balance at Mar. 31, 2024	$ 91,334	$ 46,584	$ 103		340,340		(63)	(295,630)
Ending balance, shares at Mar. 31, 2024		12,653
Beginning balance, shares at Dec. 31, 2023	4,885,512		4,885,512
Beginning balance at Dec. 31, 2023	$ 98,297	$ 91,410	$ 91		295,376		(63)	(288,517)
Beginning balance, shares at Dec. 31, 2023		24,610
Exercises of stock options, shares	128,924
Unrealized gain on investments	$ 37
Net loss	$ (21,902)
Ending balance, shares at Sep. 30, 2024	21,665,941		21,665,941
Ending balance at Sep. 30, 2024	$ 95,232	$ 45,005	$ 108		360,564		(26)	(310,419)
Ending balance, shares at Sep. 30, 2024		12,232
Beginning balance, shares at Mar. 31, 2024			16,842,512
Beginning balance at Mar. 31, 2024	91,334	$ 46,584	$ 103		340,340		(63)	(295,630)
Beginning balance, shares at Mar. 31, 2024		12,653
Issuance of common stock in connection with conversion of Series X non-voting convertible preferred stock, value		$ (1,579)
Issuance of common stock in connection with conversion of Series X non-voting convertible preferred stock, shares		(421)
Issuance of common stock	10,937	$ (1)	$ 4		10,933	$ 1,578
Issuance of common stock, shares			4,273,505	421,000
Issuance of warrants	7,225				7,225
Stock-based compensation expense	326				326
Exercises of stock options	101				101
Exercises of stock options, shares			88,068
Unrealized gain on investments	41						41
Net loss	(8,942)							(8,942)
Ending balance, shares at Jun. 30, 2024			21,625,085
Ending balance at Jun. 30, 2024	101,021	$ 45,005	$ 107		360,503		(22)	(304,572)
Ending balance, shares at Jun. 30, 2024		12,232
Stock-based compensation expense	508				508
Issuance cost	(488)				(488)
Exercises of stock options	42		$ 1		41
Exercises of stock options, shares			40,856
Unrealized gain on investments	(4)						(4)
Net loss	$ (5,847)							(5,847)
Ending balance, shares at Sep. 30, 2024	21,665,941		21,665,941
Ending balance at Sep. 30, 2024	$ 95,232	$ 45,005	$ 108		$ 360,564		$ (26)	$ (310,419)
Ending balance, shares at Sep. 30, 2024		12,232

Net Loss per Share

9 Months Ended

Sep. 30, 2024

Earnings Per Share [Abstract]

Net Loss per Share

12. Net Loss Per Share

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2024			2023			2024			2023
Numerator:
Net loss	$	(5,847	)	$	(1,827	)	$	(21,902	)	$	(8,393	)
Denominator:
Weighted average common shares outstanding—basic and diluted		21,663,089			4,541,167			16,687,473			4,541,167
Net loss per share attributable to common stockholders—basic and diluted	$	(0.27	)	$	(0.40	)	$	(1.31	)	$	(1.85	)

The Company’s potential dilutive securities, which include stock options as of September 30, 2024 and 2023, have been excluded from the computation of diluted net loss per share attributable to common stockholders whenever the effect of including them would be to reduce the net loss per share. In periods where there is a net loss, the weighted average number of shares of common stock outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The following potential shares of common stock, presented based on amounts outstanding at each period end, were excluded from the calculation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect:


	Nine Months Ended September 30,
	2024		2023
Options to purchase common stock		2,195,039		468,617
Warrants to issue shares of common stock		7,353,442		646,759
Series X Preferred Stock issued and outstanding, as converted		12,232,000		—
Total		21,780,481		1,115,376

Nature of the Business - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	3 Months Ended						9 Months Ended
	May 01, 2024	May 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023	Jul. 26, 2024	Dec. 31, 2023	Oct. 31, 2023
Class of Stock [Line Items]
Net proceeds from offering									$ 10,645	$ 0
Proceeds from collaboration agreement									34,910
Cash and cash equivalents			$ 17,652			$ 12,069			$ 17,652	12,069		$ 17,313
Number of stock sold									2,353,500
Common stock, par value			$ 0.001						$ 0.001			$ 0.001
Common Stock, Shares, Issued			21,665,941						21,665,941			4,885,512
Net loss			$ (5,847)	$ (8,942)	$ (7,113)	$ (1,827)	$ (1,787)	$ (4,779)	$ (21,902)	$ (8,393)
Accumulated deficit			(310,419)						(310,419)			$ (288,517)
Underwriting Agreement [Member]
Class of Stock [Line Items]
Net proceeds from offering	$ 17,675	$ 17,675							$ 17,675
Number of stock sold									4,273,505
Common stock, par value	$ 0.001
Lung Acquisition [Member]
Class of Stock [Line Items]
Net proceeds from offering									$ 17,536
Cash and cash equivalents			$ 17,652						$ 17,652
Number of stock sold									726,437
Common Stock, Shares, Issued													344,345
Offering Warrant Shares [Member]
Class of Stock [Line Items]
Shares issued, price per share	4.68
Offering Warrant Shares [Member] \| Underwriting Agreement [Member]
Class of Stock [Line Items]
Shares issued, price per share	$ 4.35
Offering Shares [Member]
Class of Stock [Line Items]
Proceeds from sales of stock									$ 145,467
Offering Shares [Member] \| Underwriting Agreement [Member]
Class of Stock [Line Items]
Number of stock sold	4,273,505	4,273,505
Warrants to purchase shares of common stock		4,273,505
Offering Shares [Member] \| Equity Distribution Agreement [Member] \| Citizens JMP Securities [Member]
Class of Stock [Line Items]
Common Stock, Shares, Issued											50,000
Offering Shares [Member] \| Offering Warrant Shares [Member] \| Underwriting Agreement [Member]
Class of Stock [Line Items]
Warrants to purchase shares of common stock	4,273,505
Preferred Stock [Member]
Class of Stock [Line Items]
Proceeds from sales of stock									$ 131,211

Preferred Stock

9 Months Ended

Sep. 30, 2024

Equity [Abstract]

Preferred Stock

9. Preferred Stock

The Company is authorized to issue 5,000,000 shares of preferred stock, par value $0.001 per share. As of September 30, 2024, the Company had issued 24,610 shares of Series X Preferred Stock, of which 12,232 shares of Series X Preferred Stock remained outstanding. As of December 31, 2023, 24,610 shares of Series X Preferred Stock were issued and outstanding.

On October 31, 2023, under the terms of the Lung Acquisition Agreement, at the closing of the Lung Acquisition, Aileron issued to the stockholders of Lung 344,345 shares of common stock, and 19,903 shares of Series X Preferred Stock.

and PIPE Warrants to purchase up to an aggregate of 2,353,500 shares of Aileron common stock. Refer to Note 3 for more details on the PIPE Financing in connection with the Purchase Agreement. Since the Series X Preferred Stock was sold as a unit with the PIPE Warrants according to the Purchase Agreement, the proceeds received were allocated to each instrument on a relative fair value basis. Total gross proceeds of $18,429, less $893 of issuance costs were allocated as follows: $16,795 to the Series X Preferred Stock and $741 to the PIPE Warrants. The Series X Preferred Stock and the PIPE Warrants issued in the PIPE Financing were recorded at par value of $0.001.

At the 2023 Annual Meeting, the Company’s stockholders approved the issuance, in accordance with Nasdaq Listing Rule 5635(a), of shares of common stock, upon conversion of the Company’s outstanding Series X Preferred Stock. On March 5, 2024, subject to then existing beneficial ownership limitations, 11,957 shares of Series X Preferred Stock were automatically converted into 11,957,000 shares of common stock. On May 8, 2024, individuals and entities affiliated with Bios Partners (collectively, the “Bios Entities”) provided notice to the Company and converted 421 shares of Series X Preferred Stock held by them into 421,000 shares of common stock. As of September 30, 2024, 12,232 shares of Series X Preferred Stock (which are convertible into 12,232,000 shares of common stock) remained convertible at the option of the holder thereof, subject to certain beneficial ownership limitations (as described below).

The Company evaluated the Series X Preferred Stock for liability classification in accordance with the provisions of ASC 480, Distinguishing Liabilities from Equity ("ASC 480"), and determined that equity treatment was appropriate because the Series X Preferred Stock did not meet the definition of the liability instruments. Specifically, the Series X Preferred Stock is not mandatorily redeemable and does not embody an obligation to buy back the shares outside of the Company’s control in a manner that could require the transfer of assets. The Company determined that the Series X Preferred Stock would be recorded as temporary equity, based on the guidance of ASC 480, given that it is contingently redeemable.

Each share of Series X Preferred Stock is convertible into 1,000 shares of Common Stock. The preferences, rights, and limitations initially applicable to the Series X Preferred Stock are set forth in the Certificate of Designation of Series X Non-Voting Convertible Preferred Stock (the “Certificate of Designation”).

The Series X Preferred Stock has the following characteristics:

Voting

Except as otherwise required by law, the Series X Preferred Stock does not have voting rights. However, as long as any shares of Series X Preferred Stock are outstanding, the Company will not, without the affirmative vote of the holders of a majority of the then outstanding shares of the Series X Preferred Stock, (i) alter or change adversely the powers, preferences or rights given to the Series X Preferred Stock or alter or amend the Certificate of Designation, amend or repeal any provision of, or add any provision to, the Certificate of Incorporation or by-laws of the Company, or file any articles of amendment, certificate of designations, preferences, limitations and relative rights of any series of preferred stock, if such action would adversely alter or change the preferences, rights, privileges or powers of, or restrictions provided for the benefit of the Series X Preferred Stock, (ii) issue further shares of Series X Preferred Stock or increase or decrease (other than by conversion) the number of authorized shares of Series X Preferred Stock, or (iii) enter into any agreement with respect to any of the foregoing.

Dividends

Holders of Series X Preferred Stock are entitled to receive dividends on shares of Series X Preferred Stock equal, on an as-if-converted-to-common-stock basis, and in the same form as dividends actually paid on shares of the common stock. Such dividends are not cumulative. Since the Company’s inception, no dividends have been declared or paid.

Liquidation, dissolution or winding up

The Series X Preferred Stock does not have a preference upon any liquidation, dissolution or winding-up of the Company.

Upon liquidation, dissolution or winding up of the Company, the Series X preferred stockholders shall be entitled to receive an equivalent amount of distributions as would be paid on the common stock underlying the Series X Preferred Stock, determined on an as-converted basis, pari passu with any distributions to the common stock shareholders.

Conversion

The Series X Preferred Stock is convertible into common stock at a rate of 1,000 shares of common stock for every one share of Series X Preferred Stock that is converted. The Series X Preferred Stock is subject to certain beneficial ownership limitations, including that a holder of Series X Preferred Stock is prohibited from converting shares of Series X Preferred Stock into shares of common stock if, as a result of such conversion, such holder (together with its affiliates and any other persons acting as a group together with the holder or any of its affiliates) would beneficially own more than a specified percentage (to be initially set at 19.99% and thereafter adjusted by the holder to a number not to exceed 19.99%) of the total number of shares of common stock issued and outstanding immediately after giving effect to such conversion.

Redemption

Shares of the Series X Preferred Stock are not redeemable at the election of the holder.

Maturity

The Series X Preferred Stock shall be perpetual unless converted.

Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Payables and Accruals [Abstract]
External research and development services	$ 2,207	$ 1,110
Payroll and payroll-related costs	1,453	1,178
Professional fees	847	653
Other	73	206
Total accrued expenses and other current liabilities	$ 4,580	$ 3,147

Prepaid Expenses and Other Current Assets

9 Months Ended

Sep. 30, 2024

Prepaid Expense and Other Assets, Current [Abstract]

Prepaid Expenses and Other Current Assets

5. Prepaid Expenses and Other Current Assets

Prepaid expenses and other current assets consisted of the following:


	September 30, 2024		December 31, 2023
Prepaid research and development	$	252	$	207
Other current assets		755		675
Total prepaid expenses and other current assets	$	1,007	$	882

Subsequent Event - Additional Information (Details) $ in Thousands	Oct. 31, 2024 USD ($)
Subsequent Event [Member] \| Advancium Health Network Option Agreement [Member]
Subsequent Event [Line Items]
Non-refundable fees received	$ 100

Accrued Expenses and Other Current Liabilities (Tables)

9 Months Ended

Sep. 30, 2024

Payables and Accruals [Abstract]

Summary of Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following:


	September 30, 2024		December 31, 2023
External research and development services	$	2,207	$	1,110
Payroll and payroll-related costs		1,453		1,178
Professional fees		847		653
Other		73		206
Total accrued expenses and other current liabilities	$	4,580	$	3,147

Fair Value of Financial Assets (Tables)

9 Months Ended

Sep. 30, 2024

Fair Value Disclosures [Abstract]

Summary of Assets Measured at Fair Value on Recurring Basis

The following tables present information about the Company’s assets that are measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values:


	September 30, 2024
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	7,213	$	—	$	—	$	7,213
Treasury bills	$	10,174	$	—	$	—	$	10,174
	$	17,387	$	—	$	—	$	17,387


	December 31, 2023
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	10,322	$	—	$	—	$	10,322
	$	10,322	$	—	$	—	$	10,322

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Sep. 30, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Common Stock - Schedule of Valuation Assumptions Offering Warrants (Details)	Mar. 05, 2024
Risk-free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Offering warrant valuation	4.6
Expected term (in years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Offering warrant valuation	3
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Offering warrant valuation	113.5
Expected dividend yield
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Offering warrant valuation	0
Stock price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Offering warrant valuation	3.76
Exercise price
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Offering warrant valuation	4.68

Business Acquisition - Additional Information (Detail) - USD ($) $ in Thousands	Mar. 05, 2024	Oct. 31, 2023
Lung Acquisition [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired		100.00%
Convertible Promissory Notes [Member] \| Lung Acquisition [Member] \| Purchase Agreement [Member]
Business Acquisition [Line Items]
Debt Conversion, Converted Instrument, Amount		$ 1,553
Common Stock [Member]
Business Acquisition [Line Items]
Convertible Preferred Stock, Shares Issued upon Conversion	11,957,000
Common Stock [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		344,566
Common Stock [Member] \| Whole Share [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		344,345
Common Stock [Member] \| Fractional Share [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		221
Series X Non-Voting Convertible Preferred Stock [Member]
Business Acquisition [Line Items]
Conversion of stock shares converted	11,957
Series X Non-Voting Convertible Preferred Stock [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		20,141
Convertible Preferred Stock, Shares Issued upon Conversion		1,000
Series X Non-Voting Convertible Preferred Stock [Member] \| Lung Acquisition [Member] \| Purchase Agreement [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		4,707
Percentage of discount to per share price		10.00%
Convertible Preferred Stock, Shares Issued upon Conversion		1,000
Series X Non-Voting Convertible Preferred Stock [Member] \| Whole Share [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		19,903
Series X Non-Voting Convertible Preferred Stock [Member] \| Fractional Share [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		238
Warrants [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business acquisition number of shares exercisable		(726,437)
PIPE Warrants [Member] \| Lung Acquisition [Member] \| Purchase Agreement [Member]
Business Acquisition [Line Items]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares		2,353,500
Business Acquisition, Equity Interest Issued or Issuable, Value Assigned		$ 18,429
Stock Options [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business acquisition number of shares exercisable		(1,780,459)
Common Stock and Series X Preferred Stock [Member] \| Lung Acquisition [Member]
Business Acquisition [Line Items]
Business acquisition cash in lieu of fractional shares		$ 290

Preferred Stock - Additional Information (Detail) - USD ($)					9 Months Ended
	May 08, 2024	May 05, 2024	Mar. 05, 2024	Oct. 31, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Class of Stock [Line Items]
Common stock, shares issued					21,665,941		4,885,512
Common stock, par value					$ 0.001		$ 0.001
Issuance costs					$ 893,000
Proceeds from the PIPE transaction					$ 7,030,000	$ 0
Common Stock [Member]
Class of Stock [Line Items]
Preferred Stock is automatically convertible into common stock	421,000	11,957,000	11,957,000
Preferred Stock is convertible into common stock					12,232,000
PIPE Warrants [Member]
Class of Stock [Line Items]
Preferred stock, par value					$ 0.001
Proceeds from the PIPE transaction					$ 741,000
Lung Acquisition [Member]
Class of Stock [Line Items]
Common stock, shares issued				344,345
Lung Acquisition [Member] \| Maximum [Member] \| Common Warrants [Member]
Class of Stock [Line Items]
Aggregate number of shares issued and sold				2,353,500
Series X Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares authorized					5,000,000
Preferred stock, par value					$ 0.001
Preferred stock, shares issued					24,610		24,610
Preferred stock, shares outstanding					12,232		24,610
Conversion of stock shares converted	421	11,957	11,957
Conversion of stock shares issued					12,232
Preferred Stock is convertible into common stock					1,000
Gross proceeds from issuance of preferred stock					$ 18,429,000
Proceeds from issuance of preferred stock					$ 16,795,000
Preferred stock, convertible, shares issuable beneficial ownership as a percentage					19.99%
Series X Preferred Stock [Member] \| Lung Acquisition [Member]
Class of Stock [Line Items]
Preferred stock, shares issued				19,903
Series X Preferred Stock [Member] \| Lung Acquisition [Member] \| Purchase Agreement [Member]
Class of Stock [Line Items]
Aggregate number of shares issued and sold				4,707

Prepaid Expenses and Other Current Assets (Tables)

9 Months Ended

Sep. 30, 2024

Prepaid Expense and Other Assets, Current [Abstract]

Schedule of Prepaid and Other Current Assets

Prepaid expenses and other current assets consisted of the following:


	September 30, 2024		December 31, 2023
Prepaid research and development	$	252	$	207
Other current assets		755		675
Total prepaid expenses and other current assets	$	1,007	$	882

Business Acquisition

9 Months Ended

Sep. 30, 2024

Business Combination, Asset Acquisition, and Joint Venture Formation [Abstract]

Business Acquisition

3. Business Acquisition

On October 31, 2023, Aileron acquired 100% of Lung, pursuant to the Lung Acquisition Agreement. At the closing of the Lung Acquisition, Aileron issued to the stockholders of Lung 344,345 shares of its common stock (excluding 221 fractional shares from the total 344,566 shares pursuant to the Lung Acquisition Agreement) and 19,903 shares of its newly designated Series X non-voting convertible preferred stock (the “Series X Preferred Stock”) (excluding 238 fractional shares from the total 20,141 shares pursuant to the Lung Acquisition Agreement). Each share of Series X Preferred Stock is convertible into 1,000 shares of common stock. The Company paid $290 cash in lieu of fractional shares of both common stock and Series X Preferred Stock. In addition, Aileron assumed all of Lung’s stock options (1,780,459) and all warrants (726,437) exercisable for Lung common stock immediately outstanding prior to the closing of the Lung Acquisition, each subject to adjustment pursuant to the terms of the Lung Acquisition Agreement.

Immediately following the closing of the Lung Acquisition, on October 31, 2023, Aileron entered into a Stock and Warrant Purchase Agreement (the “Purchase Agreement”) with a group of accredited investors, pursuant to which Aileron issued and sold (i) an aggregate of 4,707 shares of Series X Preferred Stock, and (ii) warrants (the “PIPE Warrants”) to purchase up to an aggregate of 2,353,500 shares of Aileron common stock (the “PIPE Warrant Shares”), for an aggregate purchase price of approximately $18,429, which included the conversion of certain convertible promissory notes in the aggregate principal amount of $1,553 issued by Lung to Bios Partners, the majority stockholder of Lung prior to the closing of the Lung Acquisition, at a 10% discount to the per share price of the Series X Preferred Stock (collectively, the “PIPE Financing”). The PIPE Financing closed on November 2, 2023. Each share of Series X Preferred Stock is convertible into 1,000 shares of common stock.

At the 2023 annual meeting of stockholders (the “2023 Annual Meeting”), the Company’s stockholders approved the issuance, in accordance with Nasdaq Listing Rule 5635(a), of shares of common stock, upon conversion of the Company’s outstanding Series X Preferred Stock. On March 5, 2024, subject to then existing beneficial ownership limitations, 11,957 shares of Series X Preferred Stock were automatically converted into 11,957,000 shares of common stock.

The Lung Acquisition was accounted for under the acquisition method of accounting under ASC 805, Business Combinations. Under the acquisition method, the total purchase price of the acquisition is allocated to the net tangible and identifiable intangible assets acquired and liabilities assumed based on the fair values as of the date of the acquisition. Consideration transferred is the sum of the acquisition-date fair values of the assets transferred, the liabilities incurred by the acquirer to the former owners of the acquiree, and the equity interests issued by the acquirer to the former owners of the acquiree (except for the measurement of share-based payment awards). The Company recorded the assets acquired and liabilities assumed as of the date of the Lung Acquisition based on the information available at that date.

Common Stock (Tables)

9 Months Ended

Sep. 30, 2024

Equity [Abstract]

Schedule of Valuation Assumption Offering Warrants

The following assumptions were used to perform the Offering Warrants valuation:


	May 3,
	2024
Risk-free interest rate		4.6	%
Expected term (in years)		3.0
Expected volatility		113.5	%
Expected dividend yield		0	%
Stock price	$	3.76
Exercise price	$	4.68

Stock-Based Awards - Summary of Stock Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 508	$ 229	$ 984	$ 920
Research and Development [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	38	37	114	227
General and Administrative [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	$ 470	$ 192	$ 870	$ 693

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Subparagraph (f)(2)(i)
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Reference 26: http://www.xbrl.org/2003/role/disclosureRef
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-Subparagraph (f)(2)(iii)
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Reference 27: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

Income Taxes

9 Months Ended

Sep. 30, 2024

Income Tax Disclosure [Abstract]

Income Taxes

13. Income Taxes

As of September 30, 2024, the Company has not recorded any U.S. federal or state income tax benefits for either the net losses it has incurred or its earned research and orphan drug credits, due to the uncertainty of realizing a benefit from those items in the future.

- Definition

The entire disclosure for income tax.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org/1943274/2147482603/740-30-50-2

+ Details

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Sep. 30, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Convertible preferred stock, par value	$ 0.001	$ 0.001
Convertible preferred stock, shares authorized	5,000,000	5,000,000
Convertible preferred stock, shares issued	24,610	24,610
Convertible preferred stock, shares outstanding	12,232	24,610
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	100,000,000	45,000,000
Common stock, shares issued	21,665,941	4,885,512
Common stock, shares outstanding	21,665,941	4,885,512

Related Party Transactions - Additional Information (Details) - shares	May 08, 2024	May 05, 2024	Mar. 05, 2024	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Number of shares owned				21,665,941			4,885,512
Common Stock [Member]
Related Party Transaction [Line Items]
Preferred Stock is automatically convertible into common stock	421,000	11,957,000	11,957,000
Number of shares owned				21,665,941	21,625,085	16,842,512	4,885,512	4,541,167	4,541,167	4,541,167	4,541,167
Bios Entities [Member]
Related Party Transaction [Line Items]
Number of shares owned				2,094,305
Percentage of beneficial ownership				9.90%
Bios Entities [Member] \| Common Stock [Member]
Related Party Transaction [Line Items]
Preferred Stock is automatically convertible into common stock	421,000
Series X Preferred Stock [Member]
Related Party Transaction [Line Items]
Conversion of stock shares converted	421	11,957	11,957
Series X Preferred Stock [Member] \| Bios Entities [Member]
Related Party Transaction [Line Items]
Conversion of stock shares converted	421

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
Revenue	$ 0	$ 0	$ 0	$ 0
Operating expenses:
Research and development	3,722	22	10,926	2,019
General and administrative	2,349	1,955	11,389	6,027
Restructuring and other costs	0	6	0	940
Total operating expenses	6,071	1,983	22,315	8,986
Loss from operations	(6,071)	(1,983)	(22,315)	(8,986)
Other income, net	224	156	413	593
Net loss	$ (5,847)	$ (1,827)	$ (21,902)	$ (8,393)
Net loss per share - basic	$ (0.27)	$ (0.4)	$ (1.31)	$ (1.85)
Net loss per share - diluted	$ (0.27)	$ (0.4)	$ (1.31)	$ (1.85)
Weighted average common shares outstanding - basic	21,663,089	4,541,167	16,687,473	4,541,167
Weighted average common shares outstanding - diluted	21,663,089	4,541,167	16,687,473	4,541,167
Comprehensive loss:
Net loss	$ (5,847)	$ (1,827)	$ (21,902)	$ (8,393)
Other comprehensive gain:
Unrealized (loss) gain on investments, net of tax of $0	(4)	2	37	48
Total other comprehensive (loss) gain	(4)	2	37	48
Total comprehensive loss	$ (5,851)	$ (1,825)	$ (21,865)	$ (8,345)

Stock-Based Awards - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Share-Based Payment Arrangement [Abstract]
Number of Shares, Beginning balance		2,212,102
Number of Shares, Granted	0	249,075	0
Number of stock options exercised		(128,924)	0
Number of Shares, Forfeited/Canceled		(51,971)
Number of Shares, Expired		(85,243)
Number of Shares, Ending balance		2,195,039		2,212,102
Number of Shares, Options exercisable		2,031,373		1,882,191
Number of Shares, Options vested and expected to vest		2,189,054		2,209,420
Weighted Average Exercise Price, Beginning balance		$ 7.42
Weighted Average Exercise Price, Granted		3.09
Weighted Average Exercise Price Per Share, Exercised		1.11
Weighted Average Exercise Price, Forfeited/Canceled		2.26
Weighted Average Exercise Price, Expired		29.46
Weighted Average Exercise Price, Ending balance		6.54		$ 7.42
Weighted Average Exercise Price, Options exercisable		6.81		7.46
Weighted Average Exercise Price, Options vested and expected to vest		$ 6.56		$ 7.41
Weighted Average Remaining Contractual Term, Outstanding		6 years		6 years
Weighted Average Remaining Contractual Term, Options exercisable		5 years 10 months 24 days		5 years 9 months 18 days
Weighted Average Remaining Contractual Term, Options vested and expected to vest		6 years		6 years
Aggregate Intrinsic Value, Beginning balance		$ 2,905
Aggregate intrinsic value of Exercised		354
Aggregate Intrinsic Value, Ending balance		3,379		$ 2,905
Aggregate Intrinsic Value, Options exercisable		3,163		2,631
Aggregate Intrinsic Value, Options vested and expected to vest		$ 3,367		$ 2,904

Stock-Based Awards (Tables)

9 Months Ended

Sep. 30, 2024

Share-Based Payment Arrangement [Abstract]

Valuation Assumptions of Stock Options Granted

The assumptions that the Company used to determine the grant-date fair value of the stock options granted to employees and directors during the three and nine months ended September 30, 2024 were as follows, presented on a weighted average basis:


	Three Months Ended September 30,			Nine Months Ended September 30,
	2024			2024
Risk-free interest rate		3.7	%		4.3	%
Expected term (in years)		5.6			5.3
Expected volatility		113.6	%		104.8	%
Expected dividend rate		0	%		0	%

Summary of Stock Option Activity

The following table summarizes the Company’s stock option activity since January 1, 2024:


	Number of Shares			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
Outstanding at January 1, 2024		2,212,102		$	7.42		6.0	$	2,905
Granted		249,075			3.09		—
Exercised		(128,924	)		1.11		—		354
Forfeited/Canceled		(51,971	)		2.26		—		—
Expired		(85,243	)		29.46		—		—
Outstanding at September 30, 2024		2,195,039			6.54		6.0		3,379

Options exercisable at September 30, 2024		2,031,373		$	6.81		5.9	$	3,163
Options vested and expected to vest at September 30, 2024		2,189,054		$	6.56		6.0	$	3,367
Options exercisable at December 31, 2023		1,882,191		$	7.46		5.8	$	2,631
Options vested and expected to vest at December 31, 2023		2,209,420		$	7.41		6.0	$	2,904

Summary of Stock Based Compensation Expense

The Company recorded stock-based compensation expense related to stock options in the following expense categories of its statements of operations and comprehensive loss:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Research and development expenses	$	38	$	37	$	114	$	227
General and administrative expenses		470		192		870		693
	$	508	$	229	$	984	$	920

Fair Value of Financial Assets - Additional Information (Detail) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Fair Value Disclosures [Abstract]
Fair Value, assets transfers into (out of) Level 3	$ 0	$ 0

Net Loss per Share - Summary of Potential Common Shares Excluded from Calculation of Diluted Net Loss per Share (Detail) - shares	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded from calculation of diluted net loss per share	21,780,481	1,115,376
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded from calculation of diluted net loss per share	2,195,039	468,617
Warrants To Issue Shares Of Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded from calculation of diluted net loss per share	7,353,442	646,759
Series X Preferred Stock Issued And Outstanding, As Converted [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares excluded from calculation of diluted net loss per share	12,232,000

Document and Entity Information - shares	9 Months Ended
Document and Entity Information - shares	Sep. 30, 2024	Nov. 12, 2024
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q3
Trading Symbol	ALRN
Entity Registrant Name	Aileron Therapeutics, Inc.
Entity Central Index Key	0001420565
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		21,665,941
Entity File Number	001-38130
Entity Tax Identification Number	13-4196017
Entity Address, Address Line One	12407 N. Mopac Expy.
Entity Address, Address Line Two	Suite 250
Entity Address, Address Line Three	#390
Entity Address, City or Town	Austin
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	78758
City Area Code	737
Local Phone Number	802-1989
Entity Shell Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	DE
Title of 12(b) Security	Common Stock, $0.001 par value per share
Security Exchange Name	NASDAQ

Stock-Based Awards

9 Months Ended

Sep. 30, 2024

Share-Based Payment Arrangement [Abstract]

Stock-Based Awards

11. Stock-Based Awards

As of September 30, 2024, the Company had five equity compensation plans, each of which was approved by its stockholders: 2006 Equity Incentive Plan, as amended (the “2006 Plan”), 2016 Stock Incentive Plan (the “2016 Plan”), 2017 Stock Incentive Plan (the “2017 Plan”), 2021 Stock Incentive Plan (the “2021 Plan”), and 2017 Employee Stock Purchase Plan (the “2017 ESPP”). The Company also assumed Lung’s 2013 Long-Term Incentive Plan (the “2013 Plan”) as a result of the Lung Acquisition.

As of September 30, 2024, the Company had 6,693 shares issuable upon exercise of outstanding options under the 2006 Plan; 8,404 shares to be issued upon exercise of outstanding options under the 2016 Plan, 98,528 shares to be issued upon exercise of outstanding options under the 2017 Plan, and 503,179 shares to be issued upon exercise of outstanding options under the 2021 Plan. No shares remained available for future awards under the 2006 Plan, the 2016 Plan, and the 2017 Plan as of September 30, 2024.

Under the 2021 Plan, shares that are expired, terminated, surrendered or canceled without having been fully exercised will be available for future awards. In addition, shares of common stock that are tendered to the Company by a participant to exercise an award are added to the number of shares of common stock available for the grant of awards.

The exercise price for stock options granted may not be less than the fair market value of the common stock as of the date of grant.

2021 Stock Incentive Plan

The Company’s 2021 Plan was approved by the Company’s stockholders on June 15, 2021 and became effective on June 16, 2021. At the 2023 Annual Meeting, the stockholders of the Company approved an amendment (the “Plan Amendment”) to the 2021 Plan to increase the number of shares of common stock issuable under the 2021 Plan by 3,000,000 shares to 3,840,254. Other than increasing the number of shares issuable under the 2021 Plan, the Plan Amendment does not make any changes to the 2021 Plan.

Under the 2021 Plan, the Company may grant incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock awards, awards of restricted stock units and other stock-based awards. The Company’s employees, officers, directors, consultants and advisors are eligible to receive awards under the 2021 Plan; however, incentive stock options may only be granted to employees. The 2021 Plan is administered by the Board or, at the discretion of the Board, by a committee of the Board. The number of shares of common stock covered by options and the date those options become exercisable, type of options to be granted, exercise prices, vesting and other restrictions are determined at the discretion of the Board, or its committee if so delegated.

Stock options granted under the 2021 Plan with service-based vesting conditions generally vest over four years and may not have a duration in excess of ten years, although options have been granted with vesting terms of less than four years.

The total number of shares of common stock that may be issued under the 2021 Plan was 3,908,718 as of September 30, 2024, of which 3,236,006 shares remained available for grant. The Company initially reserved 625,000 shares of common stock, plus the number of shares of common stock subject to outstanding awards under the 2017 Plan, the 2016 Plan and the 2006 Plan that expire, terminate or are otherwise surrendered, canceled, forfeited or repurchased by the Company at their original issuance price pursuant to a contractual repurchase right up to 314,006 shares. As of September 30, 2024, the Company had 503,179 shares to be issued upon exercise of outstanding options under the 2021 Plan.

2017 Stock Incentive Plan

The 2017 Plan was approved by the Company’s stockholders on June 16, 2017, and became effective on June 28, 2017. Under the 2017 Plan, the Company could grant incentive stock options, nonstatutory stock options, stock appreciation rights, restricted stock awards, awards of restricted stock units and other stock-based awards. The Company’s employees, officers, directors, consultants and advisors were eligible to receive awards under the 2017 Plan; however, incentive stock options could only be granted to employees. The 2017 Plan is administered by the Board or, at the discretion of the Board, by a committee of the Board. The number of shares of common stock covered by options and the date those options become exercisable, type of options granted, exercise prices, vesting and other restrictions were determined at the discretion of the Board, or its committee if so delegated.

Stock options granted under the 2017 Plan with service-based vesting conditions generally vest over four years and may not have a duration in excess of ten years, although options have been granted with vesting terms of less than four years. The exercise price for stock options granted may not be less than the fair market value of the common stock as of the date of grant.

As of the effective date of the 2021 Plan, the Board determined to grant no further awards under the 2017 Plan.

Shares that are expired, terminated, surrendered or canceled without having been fully exercised under the 2017 Plan will be available for future awards under the 2021 Plan. In addition, shares of common stock that are tendered to the Company by a participant to exercise an award are added to the number of shares of common stock available for the grant of awards under the 2021 Plan.

2017 Employee Stock Purchase Plan

On June 16, 2017, the Company’s stockholders approved the 2017 ESPP, which became effective on June 28, 2017. Under the 2017 ESPP, the number of shares of common stock that may be issued under the 2017 ESPP will automatically increase on each January 1, beginning with the fiscal year ended December 31, 2018 and continuing for each fiscal year until, and including, the fiscal year ending December 31, 2027, equal to the least of (i) 31,120 shares, (ii) 1% of the outstanding shares of common stock on such date and (iii) an amount determined by the Company’s Board. On January 1, 2023 and January 1, 2024, no additional shares were reserved for issuance under the 2017 ESPP pursuant to this provision. 7,500 shares remained available for future issuance under the 2017 ESPP as of September 30, 2024.

2013 Stock Incentive Plan

The Company assumed the 2013 Plan as a result of the Lung Acquisition. In October 2013, Lung’s Board of Directors (“Lung Board”) approved the 2013 Plan to provide long-term incentives for its employees, non-employee directors and certain consultants. As of September 30, 2024, 1,578,235 shares were reserved to be issued upon exercise of options outstanding under the 2013 Plan. These options were assumed by the Company in connection with the Lung Acquisition.

Before the Lung Acquisition, the 2013 Plan was administered by the Lung Board or, at the discretion of the Lung Board, by a committee of the Lung Board. The exercise prices, vesting and other restrictions were determined at the discretion of the Lung Board, or its committee if so delegated, except that the exercise price per share of stock options may not be less than 100% of the fair market value of the share of common stock on the date of grant and the term of stock option may not be greater than ten years. The contractual term for stock option awards is ten years. The vesting periods for equity awards were determined by the Lung Board, but generally were four years. The contractual term for stock option awards is ten years. Following the closing of the Lung Acquisition on October 31, 2023, no further awards can be granted under the 2013 Plan.

Stock Option Valuation

There were no options granted to employees or directors during the three and the nine months ended September 30, 2023. The assumptions that the Company used to determine the grant-date fair value of the stock options granted to employees and directors during the three and nine months ended September 30, 2024 were as follows, presented on a weighted average basis:


	Three Months Ended September 30,			Nine Months Ended September 30,
	2024			2024
Risk-free interest rate		3.7	%		4.3	%
Expected term (in years)		5.6			5.3
Expected volatility		113.6	%		104.8	%
Expected dividend rate		0	%		0	%

Stock Options

The following table summarizes the Company’s stock option activity since January 1, 2024:


	Number of Shares			Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term		Aggregate Intrinsic Value
Outstanding at January 1, 2024		2,212,102		$	7.42		6.0	$	2,905
Granted		249,075			3.09		—
Exercised		(128,924	)		1.11		—		354
Forfeited/Canceled		(51,971	)		2.26		—		—
Expired		(85,243	)		29.46		—		—
Outstanding at September 30, 2024		2,195,039			6.54		6.0		3,379

Options exercisable at September 30, 2024		2,031,373		$	6.81		5.9	$	3,163
Options vested and expected to vest at September 30, 2024		2,189,054		$	6.56		6.0	$	3,367
Options exercisable at December 31, 2023		1,882,191		$	7.46		5.8	$	2,631
Options vested and expected to vest at December 31, 2023		2,209,420		$	7.41		6.0	$	2,904

The weighted average grant-date fair value of stock options granted during the nine months ended September 30, 2024 was $2.46. There were no options granted to employees or directors during the nine months ended September 30, 2023. The aggregate fair value of stock options that vested during the nine months ended September 30, 2024 and 2023, was $1,453 and $1,033, respectively.

The aggregate intrinsic value of stock options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock for those stock options that had exercise prices lower than the fair value of the Company’s

common stock. The aggregate intrinsic value of stock options exercised during the nine months ended September 30, 2024 was $354. There were no stock options exercised during the nine months ended September 30, 2023.

Stock-Based Compensation

The Company recorded stock-based compensation expense related to stock options in the following expense categories of its statements of operations and comprehensive loss:


	Three Months Ended September 30,				Nine Months Ended September 30,
	2024		2023		2024		2023
Research and development expenses	$	38	$	37	$	114	$	227
General and administrative expenses		470		192		870		693
	$	508	$	229	$	984	$	920

As of September 30, 2024, the Company had an aggregate of $232 of unrecognized stock-based compensation expense, which it expects to recognize over a weighted average period of 1.65 years.

On March 11, 2024, the Company and Manuel C. Alves-Aivado, M.D., Ph.D., agreed that his employment with the Company would cease and he would resign from his position as Chief Executive Officer ("CEO") of the Company, effective as of March 11, 2024. Dr. Aivado remains a member of the Company’s Board. Dr. Aivado’s resignation from the Company was not the result of any disagreement with the Company on any matter relating to its operations, policies or practices. As a non-employee director, following the separation date, Dr. Aivado will be compensated in accordance with the terms of the Company’s non-employee director compensation program. In addition, Dr. Aivado will continue to vest in all unvested stock option awards pursuant to the amended vesting terms. The resignation of Dr. Aivado as CEO was considered a significant reduction in service and his original awards were deemed to have been modified and accounted for as a Type III modification with no material effect on these condensed consolidated financial statements.

Other Assets

9 Months Ended

Sep. 30, 2024

Prepaid Expense and Other Assets [Abstract]

Other Assets

7. Other Assets

Other assets consisted of the following:


	September 30, 2024		December 31, 2023
Non-current prepaid research and development	$	—	$	2,140
Other assets		2		53
Total other non-current assets	$	2	$	2,193

The non-current prepaid research and development was fully expensed during the nine months ended September 30, 2024 due to the temporary delay of clinical development of LTI-01.

Related Party Transactions

9 Months Ended

Sep. 30, 2024

Related Party Transactions

14. Related Party Transactions

On May 8, 2024, the Bios Entities converted 421 shares of the Company’s Series X Preferred Stock into 421,000 shares of common stock. After the conversion, as of September 30, 2024, the Bios Entities owned 2,094,305 shares of the Company’s common stock resulting in a beneficial ownership of 9.9% of the Company’s outstanding common stock.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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-Paragraph 2
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Cash flows from operating activities:
Net loss	$ (21,902)	$ (8,393)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	63	67
Net amortization of premiums and discounts on investments	0	(156)
Stock-based compensation expense	984	920
Gain on sale of property and equipment	0	(42)
Loss on disposition of property and equipment	0	16
Changes in operating assets and liabilities:
Prepaid expenses and other current assets	(89)	(93)
Other assets	2,191	24
Accounts payable	(111)	(1,236)
Operating lease liabilities	(48)	(33)
Accrued expenses and other current liabilities	1,433	(491)
Net cash used in operating activities	(17,479)	(9,417)
Cash flows from investing activities:
Proceeds from sale of property and equipment	0	42
Proceeds from sales or maturities of investments	0	16,250
Net cash provided by investing activities	0	16,292
Cash flows from financing activities:
Proceeds from issuance of common stock, net of offering costs	10,645	0
Proceeds from issuance of common stock in connection with stock option exercises	142	0
Proceeds from issuance of warrants, net of offering costs	7,030	0
Net cash provided by financing activities	17,817	0
Effect of exchange rate changes on cash and cash equivalents	1	0
Net increase in cash, cash equivalents and restricted cash	339	6,875
Cash, cash equivalents and restricted cash at beginning of period	17,338	5,219
Cash, cash equivalents and restricted cash at end of period	17,677	12,094
Cash and cash equivalents at end of period	17,652	12,069
Restricted cash at end of period	25	25
Cash, cash equivalents and restricted cash at end of period	17,677	12,094
Supplemental disclosure of non-cash investing and financing activities:
Conversion of Series X non-voting convertible preferred stock into common stock shares	$ 46,405	$ 0

Net Loss per Share - Basic and Diluted Net Loss per Share Attributable to Common Stockholders (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Numerator:
Net loss	$ (5,847)	$ (8,942)	$ (7,113)	$ (1,827)	$ (1,787)	$ (4,779)	$ (21,902)	$ (8,393)
Denominator:
Weighted average common shares outstanding - basic	21,663,089			4,541,167			16,687,473	4,541,167
Weighted average common shares outstanding - diluted	21,663,089			4,541,167			16,687,473	4,541,167
Net loss per share - basic	$ (0.27)			$ (0.4)			$ (1.31)	$ (1.85)
Net loss per share - diluted	$ (0.27)			$ (0.4)			$ (1.31)	$ (1.85)

- Definition

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

+ References

+ Details

- Definition

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.

+ References

+ Details

- Definition

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

+ References

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+ Details

Stock-Based Awards - Additional Information (Detail) $ / shares in Units, $ in Thousands			3 Months Ended	9 Months Ended
	Oct. 31, 2023 shares	Jun. 16, 2017 shares	Sep. 30, 2023 shares	Sep. 30, 2024 USD ($) Plan $ / shares shares	Sep. 30, 2023 USD ($) shares	Feb. 28, 2024 shares	Dec. 31, 2023 shares	Jan. 01, 2023 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted average grant-date fair value of stock options \| $ / shares				$ 2.46
Number of options granted to employees or directors			0	249,075	0
Aggregate fair value of stock options vested \| $				$ 1,453	$ 1,033
Aggregate unrecognized stock-based compensation expense \| $				$ 232
Unrecognized stock-based compensation expense, weighted average period expects for recognition				1 year 7 months 24 days
Number of stock options exercised				128,924	0
Number of equity compensation plans \| Plan				5
Number of shares, issued upon exercise of outstanding options				2,195,039			2,212,102
Aggregate intrinsic value of stock options exercised \| $				$ 354
2021 Stock Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option granted vesting period				4 years
Number of shares, available for grant				3,908,718
Number of shares remained available for grant				3,236,006
Stock reserved for future issuance				3,236,006
Number of shares, issued upon exercise of outstanding options				503,179
Increase in common stock				3,840,254		3,000,000
2021 Stock Incentive Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option granted vesting period				4 years
Stock option expiration period				10 years
2017 Stock Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option granted vesting period				4 years
Stock reserved for future issuance				625,000
Number of shares, issued upon exercise of outstanding options				98,528
Number of shares remained available for future issuance				0
2017 Stock Incentive Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option granted vesting period				4 years
Stock option expiration period				10 years
2006 Stock Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual repurchase right, shares				314,006
Number of shares, issued upon exercise of outstanding options				6,693
Number of shares remained available for future issuance				0
2016 Stock Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, issued upon exercise of outstanding options				8,404
Number of shares remained available for future issuance				0
2017 Employee Stock Purchase Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, available for grant				7,500
Stock reserved for future issuance				7,500				0
Percentage of common stock shares outstanding		1.00%
Stock incentive plan description				On June 16, 2017, the Company’s stockholders approved the 2017 ESPP, which became effective on June 28, 2017. Under the 2017 ESPP, the number of shares of common stock that may be issued under the 2017 ESPP will automatically increase on each January 1, beginning with the fiscal year ended December 31, 2018 and continuing for each fiscal year until, and including, the fiscal year ending December 31, 2027, equal to the least of (i) 31,120 shares, (ii) 1% of the outstanding shares of common stock on such date and (iii) an amount determined by the Company’s Board. On January 1, 2023 and January 1, 2024, no additional shares were reserved for issuance under the 2017 ESPP pursuant to this provision. 7,500 shares remained available for future issuance under the 2017 ESPP as of September 30, 2024.
Maximum annual increase in common stock reserved for future issuance		31,120
2013 Stock Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted to employees or directors	0
2013 Stock Incentive Plan [Member] \| Lung Acquisition [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option granted vesting period				4 years
2013 Stock Incentive Plan [Member] \| Options Outstanding [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, available for grant				1,578,235
Contractual terms of stock option awards				10 years
2013 Stock Incentive Plan [Member] \| Options Outstanding [Member] \| Lung Acquisition [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual terms of stock option awards				10 years
2013 Stock Incentive Plan [Member] \| Maximum [Member] \| Options Outstanding [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual terms of stock option awards				10 years
2013 Stock Incentive Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of fair market value of common stock				100.00%

Fair Value of Financial Assets - Summary of Assets Measured at Fair Value on Recurring Basis (Detail) - Recurring [Member] - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total Fair Value of Financial Instruments	$ 17,387	$ 10,322
Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total Fair Value of Financial Instruments	17,387	10,322
Money Market Funds [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	7,213	10,322
Money Market Funds [Member] \| Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	7,213	$ 10,322
Treasury Bills [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	10,174
Treasury Bills [Member] \| Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Cash equivalents	$ 10,174

Net Loss per Share (Tables)

9 Months Ended

Sep. 30, 2024

Earnings Per Share [Abstract]

Basic and Diluted Net Loss per Share Attributable to Common Stockholders

Basic and diluted net loss per share attributable to common stockholders was calculated as follows:


	Three Months Ended September 30,						Nine Months Ended September 30,
	2024			2023			2024			2023
Numerator:
Net loss	$	(5,847	)	$	(1,827	)	$	(21,902	)	$	(8,393	)
Denominator:
Weighted average common shares outstanding—basic and diluted		21,663,089			4,541,167			16,687,473			4,541,167
Net loss per share attributable to common stockholders—basic and diluted	$	(0.27	)	$	(0.40	)	$	(1.31	)	$	(1.85	)

Summary of Potential Common Shares Excluded from Calculation of Diluted Net Loss per Share

The following potential shares of common stock, presented based on amounts outstanding at each period end, were excluded from the calculation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect:


	Nine Months Ended September 30,
	2024		2023
Options to purchase common stock		2,195,039		468,617
Warrants to issue shares of common stock		7,353,442		646,759
Series X Preferred Stock issued and outstanding, as converted		12,232,000		—
Total		21,780,481		1,115,376

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 17,652	$ 17,313
Prepaid expenses and other current assets	1,007	882
Restricted cash	25	25
Operating lease, right-of-use asset, current portion		46
Total current assets	18,684	18,266
Property and equipment, net	1	19
Goodwill	6,330	6,330
Intangible assets	79,200	79,200
Other non-current assets	2	2,193
Total assets	104,217	106,008
Current liabilities:
Accounts payable	1,079	1,190
Accrued expenses and other current liabilities	4,580	3,147
Operating lease liabilities, current portion		48
Total current liabilities	5,659	4,385
Deferred tax liability	3,326	3,326
Total liabilities	8,985	7,711
Commitments and contingencies (Note 15)
Convertible preferred stock, $0.001 par value, 5,000,000 shares authorized at September 30, 2024 and at December 31, 2023; 24,610 shares issued and 12,232 shares outstanding at September 30, 2024 and 24,610 shares issued and outstanding at December 31, 2023	45,005	91,410
Stockholders’ equity:
Common stock, $0.001 par value; 100,000,000 shares authorized at September 30, 2024 and 45,000,000 at December 31, 2023; 21,665,941 shares and 4,885,512 shares issued and outstanding at September 30, 2024 and December 31, 2023, respectively	108	91
Additional paid-in capital	360,564	295,376
Accumulated other comprehensive loss	(26)	(63)
Accumulated deficit	(310,419)	(288,517)
Total liabilities, convertible preferred stock and stockholders' equity	$ 104,217	$ 106,008

Common Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands						1 Months Ended	9 Months Ended		12 Months Ended
	May 08, 2024	May 05, 2024	May 01, 2024	Mar. 05, 2024	Oct. 31, 2023	May 31, 2024	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023	Jul. 26, 2024	Jun. 30, 2024	Mar. 31, 2024	Feb. 28, 2024	Jun. 30, 2023	Mar. 31, 2023	Jan. 01, 2023	Dec. 31, 2022
Class of Stock [Line Items]
Common stock, shares authorized							100,000,000		45,000,000				100,000,000
Common stock, par value							$ 0.001		$ 0.001
Net proceeds from offering							$ 10,645	$ 0
Common stock, shares issued							21,665,941		4,885,512
Common stock, shares outstanding							21,665,941		4,885,512
Common stock voting rights							Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders.
Common stock, dividends declared							$ 0		$ 0
Aggregate number of common stock shares issued and sold							2,353,500
Treasury stock							0
Shares issued, outstanding and reserved for issuance							46,926,928
Series X Preferred Stock [Member]
Class of Stock [Line Items]
Warrants exercise price							$ 4.89
Conversion of stock shares converted	421	11,957		11,957
Preferred stock, shares issued							24,610		24,610
Conversion of stock shares issued							12,232
Preferred Stock is convertible into common stock							1,000
Preferred stock, shares outstanding							12,232		24,610
Common stock reserved for issuance							12,469,000
Warrants and Rights Outstanding, Maturity Date							May 02, 2027
Common Stock [Member]
Class of Stock [Line Items]
Common stock, shares outstanding							21,665,941	4,541,167	4,885,512		21,625,085	16,842,512		4,541,167	4,541,167		4,541,167
Preferred Stock is automatically convertible into common stock	421,000	11,957,000		11,957,000
Preferred Stock is convertible into common stock							12,232,000
Stock remained available for future issuance							53,073,072
Warrants [Member]
Class of Stock [Line Items]
Percentage of common stock share outstanding							9.99%
Issuance of warrants							$ 8,000
Common stock reserved for issuance							7,353,442
Warrants [Member] \| Minimum [Member]
Class of Stock [Line Items]
Percentage of common stock share outstanding							4.99%
PIPE Warrants [Member]
Class of Stock [Line Items]
Warrants exercise price					$ 4.89
Issuance of warrants							$ 741
PIPE Warrants [Member] \| Maximum [Member]
Class of Stock [Line Items]
Percentage of common stock share outstanding							19.99%
Existing Equity Incentive Plans [Member]
Class of Stock [Line Items]
Common stock reserved for issuance							2,195,039
2021 Stock Incentive Plan [Member]
Class of Stock [Line Items]
Common stock reserved for issuance							3,236,006
Stock remained available for future issuance							3,908,718
2017 Employee Stock Purchase Plan [Member]
Class of Stock [Line Items]
Common stock reserved for issuance							7,500									0
Stock remained available for future issuance							7,500
Lung Acquisition [Member]
Class of Stock [Line Items]
Net proceeds from offering							$ 17,536
Warrants exercise price							$ 5.66
Common stock, shares issued					344,345
Aggregate number of common stock shares issued and sold							726,437
Warrants and Rights Outstanding, Maturity Date							May 20, 2029
Lung Acquisition [Member] \| Series X Preferred Stock [Member]
Class of Stock [Line Items]
Preferred stock, shares issued					19,903
Aggregate number of common stock shares issued and sold					4,707
Lung Acquisition [Member] \| PIPE Warrants [Member] \| Maximum [Member]
Class of Stock [Line Items]
Aggregate number of common stock shares issued and sold					2,353,500
Underwriting Agreement [Member]
Class of Stock [Line Items]
Common stock, par value			$ 0.001
Net proceeds from offering			$ 17,675			$ 17,675	$ 17,675
Warrants exercise price							$ 4.68
Underwriter purchased price						$ 4.35
Aggregate number of common stock shares issued and sold							4,273,505
Warrants and Rights Outstanding, Maturity Date							May 03, 2027
Underwriting Agreement [Member] \| Common Stock [Member]
Class of Stock [Line Items]
Offering price						$ 4.68
Warrants exercise price							$ 4.68
Aggregate number of common stock shares issued and sold			4,273,505			4,273,505
Warrants to purchase shares of common stock						4,273,505
Equity Distribution Agreement [Member] \| Citizens Jmp Securities [Member] \| Common Stock [Member]
Class of Stock [Line Items]
Common stock, shares issued										50,000

Prepaid Expenses and Other Current Assets - Schedule of Prepaid and Other Current Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid research and development	$ 252	$ 207
Other current assets	755	675
Total prepaid expenses and other current assets	$ 1,007	$ 882

Stock-Based Awards - Valuation Assumptions of Stock Options Granted (Detail)	3 Months Ended	9 Months Ended
	Sep. 30, 2024	Sep. 30, 2024
Share-Based Payment Arrangement [Abstract]
Risk-free interest rate	3.70%	4.30%
Expected term (in years)	5 years 7 months 6 days	5 years 3 months 18 days
Expected volatility	113.60%	104.80%
Expected dividend rate	0.00%	0.00%

Fair Value of Financial Assets

9 Months Ended

Sep. 30, 2024

Fair Value Disclosures [Abstract]

Fair Value of Financial Assets

4. Fair Value of Financial Assets


	September 30, 2024
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	7,213	$	—	$	—	$	7,213
Treasury bills	$	10,174	$	—	$	—	$	10,174
	$	17,387	$	—	$	—	$	17,387


	December 31, 2023
	Level 1		Level 2		Level 3		Total
Cash equivalents:
Money market funds	$	10,322	$	—	$	—	$	10,322
	$	10,322	$	—	$	—	$	10,322

During the nine months ended September 30, 2024 and the year ended December 31, 2023, there were no transfers between levels.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 107
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478119/940-820-50-1

+ Details

Commitments and Contingencies - Additional Information (Detail) $ / shares in Units, $ in Thousands			1 Months Ended		9 Months Ended		12 Months Ended
	Aug. 16, 2021 ft²	Feb. 06, 2015 shares	Mar. 31, 2018 USD ($) $ / shares shares	Jun. 30, 2013 shares	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)	Feb. 28, 2010 USD ($)
Harvard and Dana-Farber Agreement [Member] \| Therapeutic Product [Member]
Other Commitments [Line Items]
Aggregate milestones payments								$ 7,700
Harvard and Dana-Farber Agreement [Member] \| Diagnostic Product [Member]
Other Commitments [Line Items]
Aggregate milestones payments								$ 700
Harvard and Dana-Farber Agreement [Member] \| License [Member]
Other Commitments [Line Items]
Annual license maintenance fees							$ 35
Harvard and Dana-Farber Agreement [Member] \| License and Maintenance [Member]
Other Commitments [Line Items]
Annual license maintenance fees					$ 27	$ 0	$ 110
Operating Lease Agreement [Member]
Other Commitments [Line Items]
Area of land \| ft²	6,455
Lease expiration date	Mar. 31, 2024
UTHSCT Agreement [Member] \| Common Stock [Member]
Other Commitments [Line Items]
Shares granted in consideration \| shares		4,000,000		2,000,000
UTHSCT Agreement [Member] \| Non-convertible preferred stock [Member]
Other Commitments [Line Items]
Shares granted in consideration \| shares		400,000		400,000
MUSC Agreement [Member] \| License [Member]
Other Commitments [Line Items]
Annual license maintenance fees					$ 25	$ 0
Vivarta Therapeutics LLC [Member]
Other Commitments [Line Items]
License fee on agreement effective date			$ 10,000
License fee on receipt of positive freedom to operate analysis from legal counsel			$ 40,000
Vivarta Therapeutics LLC [Member] \| Common Stock [Member]
Other Commitments [Line Items]
Issuance of common stock warrant \| shares			75,000
Warrant per share \| $ / shares			$ 0.12

Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and as amended by ASUs of the Financial Accounting Standards Board (“FASB”). Unaudited Interim Financial Information The accompanying unaudited condensed consolidated financial statements as of September 30, 2024 and for the nine months ended September 30, 2024 and 2023 have been prepared by the Company pursuant to the rules and regulations of the United States Securities and Exchange Commission (the “SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. However, the Company believes that the disclosures are adequate to make the information presented not misleading. These financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023 that was filed with the SEC on April 15, 2024. The condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of September 30, 2024, the results of its operations for the three and nine months ended September 30, 2024 and 2023 and its cash flows for the nine months ended September 30, 2024 and 2023. The financial data and other information disclosed in these notes related to the three and nine months ended September 30, 2024 and 2023 are unaudited. The results for the nine months ended September 30, 2024 are not necessarily indicative of results to be expected for the year ending December 31, 2024, any other interim periods, or any future year or period. The accompanying balance sheet as of December 31, 2023 has been derived from the Company’s audited consolidated financial statements for the year ended December 31, 2023 included in the Company’s Annual Report on Form 10-K. The Company’s significant accounting policies are described in Note 2 to the consolidated financial statements included in the Annual Report on Form 10-K for the year ended December 31, 2023.
Principles of Consolidation	Principles of Consolidation The accompanying condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Lung Therapeutics, LLC, Lung Therapeutics Australia Pty Ltd, and Lung Therapeutics Limited. Lung Therapeutics Limited is currently inactive. All intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, the accrual for research and development expenses, the prepaid research and development expenses, and the value of stock-based compensation. Estimates are periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates.
Concentration of Credit Risk and of Significant Suppliers	Concentration of Credit Risk and of Significant Suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. Periodically, the Company maintains balances in operating accounts above federally insured limits. The Company deposits its cash in financial institutions that it believes have high credit quality. The Company has not experienced any losses on such accounts and does not believe it is exposed to any significant credit risk on cash and cash equivalents. The Company is dependent on third-party manufacturers to supply products for research and development activities of its programs, including preclinical and clinical testing. In particular, the Company relies on a small number of manufacturers to supply it with its requirements for the active pharmaceutical ingredients and formulated drugs related to these programs. These programs could have been adversely affected by a significant interruption in the supply of active pharmaceutical ingredients and formulated drugs.
Recently Issued Accounting Pronouncements	Accounting Pronouncements Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income (Topic 220): Disaggregation of Income Statement Expenses (“ASU 2024-03”), to enhance the transparency and decision usefulness of financial information presented in the income statement by requiring disaggregated information about certain income statement expense line items. This ASU is effective for annual periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. The Company has not evaluated the impact of this ASU on its consolidated financial statements and related disclosures. In March 2024, the FASB issued ASU 2024-02, Codification Improvements—Amendments to Remove References to the Concepts Statements, that contains amendments to the Codification that remove references to various FASB Concepts Statements. This effort facilitates Codification updates for technical corrections such as conforming amendments, clarifications to guidance, simplifications to wording or the structure of guidance, and other minor improvements. The amendments are effective for public business entities for fiscal years beginning after December 15, 2024, with early adoption permitted. Early application of the amendments in this ASU is permitted for all entities, for any fiscal year or interim period for which financial statements have not yet been issued (or made available for issuance). If an entity adopts the amendments in an interim period, it must adopt them as of the beginning of the fiscal year that includes that interim period. The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures. In March 2024, the FASB issued ASU 2024-01, Compensation—Stock Compensation (Topic 718): Scope Application of Profits Interest and Similar Awards, to improve GAAP by adding an illustrative example that includes four fact patterns to demonstrate how an entity should apply the scope guidance in paragraph 718-10-15-3 to determine whether a profits interest award should be accounted for in accordance with Topic 718, Compensation—Stock Compensation. For public business entities, the amendments in this ASU are effective for annual periods beginning after December 15, 2024, and interim periods within those annual periods. Early adoption is permitted for both interim and annual financial statements that have not yet been issued or made available for issuance. If an entity adopts the amendments in an interim period, it should adopt them as of the beginning of the annual period that includes that interim period. The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, to enhance the transparency and decision usefulness of income tax disclosures by requiring disaggregated information about an entity’s effective tax rate reconciliation, as well as information on taxes paid. This ASU is effective for annual periods beginning after December 15, 2024. Interim disclosures are not impacted by this update. The Company has not evaluated the impact of these amendments on its annual disclosures. In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Segment Disclosures, to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This ASU is effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024. The Company is evaluating the impact of the new requirements, effective for its 2024 consolidated financial statements, to determine the level of disclosure of segment expenses.

Goodwill and Indefinite-Lived Intangible Assets - Additional Information (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Indefinite-Lived Intangible Assets [Line Items]
Goodwill	$ 6,330,000	$ 6,330,000
Indefinite-lived intangible assets acquired	79,200,000
Impairment of goodwill	0
Impairment of indefinite-lived intangible assets	$ 0

- Definition

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 49
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-49

Reference 2: http://www.xbrl.org/2003/role/exampleRef
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
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Reference 4: http://www.xbrl.org/2003/role/exampleRef
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+ Details

Other Assets - Schedule of Other Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Prepaid Expense and Other Assets [Abstract]
Non-current prepaid research and development	$ 0	$ 2,140
Other assets	2	53
Total other non-current assets	$ 2	$ 2,193

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Thousands	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Pay vs Performance Disclosure
Net Income (Loss)	$ (5,847)	$ (8,942)	$ (7,113)	$ (1,827)	$ (1,787)	$ (4,779)	$ (21,902)	$ (8,393)

- Definition

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

+ References

+ Details

Subsequent Event

9 Months Ended

Sep. 30, 2024

Subsequent Events [Abstract]

Subsequent Event

16. Subsequent Event

Exclusive Option Agreement with Advancium

On October 31, 2024, the Company entered into an exclusive option agreement with Advancium Health Network (“Advancium”) for the sale of ALRN-6924. During the option period, Advancium intends to evaluate ALRN-6924 as a potential therapy for retinoblastoma. Under the terms of the option agreement Advancium paid the Company a non-refundable fee of $100 for the exclusive option to acquire ALRN-6924 and related assets. If Advancium exercises its option, the Company will receive an exercise payment with potential for additional development, regulatory and commercial milestone payments and sales royalties.

Common Stock

9 Months Ended

Sep. 30, 2024

Equity [Abstract]

Common Stock

10. Common Stock

On February 28, 2024, the Company held the 2023 Annual Meeting, at which the Company’s stockholders approved an amendment to the Company’s Restated Certificate of Incorporation, as amended, to increase the number of authorized shares of common stock of the Company from 45,000,000 to 100,000,000 shares. The Company filed the Certificate of Amendment to implement the increase in the number of authorized shares, which was effective upon filing, with the Secretary of State of the State of Delaware on February 28, 2024. The additional shares of common stock authorized by the Certificate of Amendment have rights identical to the Company’s currently outstanding common stock. As of September 30, 2024 and December 31, 2023, the Company was authorized to issue 100,000,000 and 45,000,000 shares of common stock, respectively, par value $0.001 per share.

As of September 30, 2024, the Company had 21,665,941 shares of common stock issued and outstanding. As of December 31, 2023, the Company had 4,885,512 shares of common stock issued and outstanding.

Each share of common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. Common stockholders are entitled to receive dividends, as may be declared by the Company’s Board of Directors (the “Board”), if any. As of September 30, 2024 and December 31, 2023, no dividends had been declared.

In the event of liquidation or dissolution, the holders of the common stock are entitled to receive proportionately all assets available for distribution to stockholders after the payment of all debts and other liabilities and subject to the prior rights of any outstanding preferred stock.

Issuance of Common Stock and Warrants

On July 26, 2024, the Company entered into an Equity Distribution Agreement with Citizens JMP, as agent and/or principal, under which the Company may offer and sell up to $50,000 of shares of its common stock from time to time through or to Citizens JMP. Sales of common stock through or to Citizens JMP may be made by any method that is deemed an “at the market” offering as defined in Rule 415(a)(4) under the Securities Act of 1933, as amended, including sales made directly on or through the Nasdaq Capital Market. The Company did not sell any shares of common stock pursuant to the Equity Distribution Agreement during the nine months ended September 30, 2024.

In May 2024, the Company completed an underwritten follow-on public offering, pursuant to which the Company issued and sold 4,273,505 shares of the Company’s common stock and accompanying warrants to purchase 4,273,505 shares of common stock. All of the Offering Shares and Offering Warrants were sold by the Company. Each Offering Share was offered and sold together with an accompanying Offering Warrant at a combined offering price of $4.68, and the underwriter purchased each Offering Share and accompanying Offering Warrant at a combined price of $4.35. Net proceeds from the Offering were approximately $17,675, after deducting underwriting discounts and commissions and offering expenses, and excluding any proceeds that may be received from exercise of the Offering Warrants. The Offering closed on May 3, 2024.

Each Offering Warrant has an exercise price per share of common stock equal to $4.68. Each Offering Warrant may be exercised until May 1, 2027. Each Offering Warrant is exercisable solely by means of a cash exercise, except that an Offering Warrant is exercisable via cashless exercise if at the time of exercise, a registration statement registering the issuance of Offering Warrant Shares is not then effective or the prospectus contained therein is not available for the issuance of Offering Warrant Shares.

The Offering Warrants include certain rights upon “fundamental transactions” as described in the Offering Warrants, including the right of the holders thereof to receive from the Company or a successor entity the same type or form of consideration (and in the same proportion) that is being offered and paid to the holders of common stock in such fundamental transaction (as described in such Offering Warrants) of the unexercised portion of the applicable Warrants immediately prior to such fundamental transaction. A holder of Offering Warrants (together with its affiliates) may not exercise any portion of an Offering Warrant to the extent that the holder would beneficially own more than 4.99% (or, at the election of the holder, 9.99%) of the Company’s outstanding common stock immediately after exercise.

The Company has assessed the Offering Warrants for appropriate equity or liability classification and determined the Offering Warrants are freestanding instruments that do not meet the definition of a liability pursuant to ASC 480 and do not meet the definition of a derivative pursuant to ASC 815, Derivatives and Hedging (“ASC 815”). The Offering Warrants are indexed to the Company’s common stock and meet all other conditions for equity classification under ASC 480 and ASC 815. Accordingly, the Offering Warrants are classified as equity and accounted for as a component of additional paid-in capital at the time of issuance. The Offering Warrants were initially recognized at their relative fair value in the amount of $8.0 million at the time of issuance determined using Black-Scholes option-pricing model and will not be remeasured.

The following assumptions were used to perform the Offering Warrants valuation:


	May 3,
	2024
Risk-free interest rate		4.6	%
Expected term (in years)		3.0
Expected volatility		113.5	%
Expected dividend yield		0	%
Stock price	$	3.76
Exercise price	$	4.68

At the 2023 Annual Meeting, the Company’s stockholders also approved the issuance, in accordance with Nasdaq Listing Rule 5635(a), of shares of common stock, upon conversion of the Company’s outstanding Series X Preferred Stock. On March 5, 2024, subject to then existing beneficial ownership limitations, 11,957 shares of Series X Preferred Stock were automatically converted into 11,957,000 shares of common stock.

On October 31, 2023, Aileron acquired Lung. Under the terms of the Lung Acquisition Agreement, at the closing of the Lung Acquisition, Aileron issued to the stockholders of Lung 344,345 shares of common stock and 19,903 shares of Series X Preferred Stock.

Immediately following the closing of the Lung Acquisition, on October 31, 2023, Aileron entered into the Purchase Agreement with a group of accredited investors, pursuant to which Aileron issued and sold an aggregate of 4,707 shares of Series X Preferred Stock and PIPE Warrants to purchase up to an aggregate of 2,353,500 shares of Aileron common stock. Refer to Note 3 for more details on the PIPE Financing in connection with the Purchase Agreement. The exercise price of the PIPE Warrants is $4.89 per share, subject to certain price and share adjustments, including for stock splits, stock dividends, recapitalizations, subdivisions, combinations, reclassifications, noncash distributions, and cash dividends. The PIPE Warrants are exercisable on or prior to May 2, 2027. Payment for the PIPE Warrant Shares upon exercise of the PIPE Warrants may be (i) in cash or (ii) in the event that there is no registration statement available for the resale of the PIPE Warrant Shares, by cashless exercise.

Under the terms of the PIPE Warrants, the Company shall not effect the exercise of any portion of any PIPE Warrant, and a holder shall not have the right to exercise any portion of any PIPE Warrant, to the extent that after giving effect to such exercise, the holder (together with its affiliates and any other persons acting as a group together with the holder or any of its affiliates), would beneficially own in excess of a percentage elected by the holder up to 19.99% of the number of shares of common stock outstanding immediately after giving effect to such exercise, as such percentage ownership is determined in accordance with the terms of the PIPE Warrants. However, any holder may, upon written notice to the Company, increase or decrease such percentage to any other percentage not in excess of 19.99%; provided that any increase or decrease in such percentage will not be effective until 61 days after such notice is delivered to the Company.

The Company has assessed the PIPE Warrants for appropriate equity or liability classification and determined the PIPE Warrants are freestanding instruments that do not meet the definition of a liability pursuant to ASC 480 and do not meet the definition of a derivative pursuant to ASC 815. The PIPE Warrants are indexed to the Company’s common stock and meet all other conditions for equity classification under ASC 480 and ASC 815. Accordingly, the PIPE Warrants are classified as equity and accounted for as a component of additional paid-in capital at the time of issuance. The PIPE Warrants were initially recognized at their relative fair value in the amount of $741 at the time of issuance determined using Black-Scholes option-pricing model and will not be remeasured.

As of September 30, 2024, 21,665,941 shares of common stock were issued and outstanding, no shares were held in treasury, and 24,610 shares of Series X Preferred Stock had been issued, of which 12,232 shares of Series X Preferred Stock remained outstanding. In addition, as of September 30, 2024, there were:

•

12,469,000 shares of common stock reserved for issuance upon conversion of the Series X Preferred Stock;

•

2,195,039 shares of common stock issuable upon the exercise of options under existing equity incentive plans;

•

3,236,006 and 7,500 shares of common stock reserved for issuance under the 2021 Plan (as defined below) and 2017 ESPP (as defined below), respectively, as well as any automatic increases in the number of shares of the common stock reserved under these plans; and

•

7,353,442 shares of common stock reserved for issuance upon exercise of outstanding warrants. The warrants consist of (i) warrants to purchase 726,437 shares of the Company’s common stock, with an exercise price of $5.66, which expire on May 20, 2029, which were assumed in connection with the Lung Acquisition, (ii) warrants to purchase 2,353,500 shares of the Company’s common stock, with an exercise price of $4.89 per share, which were issued and sold in the PIPE Financing as described above and expire on May 2, 2027, and (iii) warrants to purchase 4,273,505 shares of the Company’s common stock, with an exercise price of $4.68 per share, which were issued and sold in the Offering as described above and expire on May 3, 2027.

Accordingly, as of September 30, 2024, out of the 100,000,000 shares of common stock presently authorized, 46,926,928 shares are issued and outstanding or reserved for issuance and 53,073,072 shares of common stock remain available for future issuance.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 13
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 40
-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
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Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-URI https://asc.fasb.org/505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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Reference 14: http://www.xbrl.org/2003/role/disclosureRef
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Other Assets (Tables)

9 Months Ended

Sep. 30, 2024

Prepaid Expense and Other Assets [Abstract]

Schedule of Other Assets

Other assets consisted of the following:


	September 30, 2024		December 31, 2023
Non-current prepaid research and development	$	—	$	2,140
Other assets		2		53
Total other non-current assets	$	2	$	2,193

Condensed Consolidated Statements of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Income Statement [Abstract]
Unrealized gain on investments, tax	$ 0	$ 0	$ 0	$ 0

Nature of the Business

9 Months Ended

Sep. 30, 2024

Accounting Policies [Abstract]

Nature of the Business

1. Nature of the Business

Aileron Therapeutics, Inc. (“Aileron” or the “Company”) is a clinical stage biopharmaceutical company focused on developing novel therapies for the treatment of orphan pulmonary and fibrosis indications with no approved or limited effective treatments. The Company currently has two product candidates in clinical development, LTI-03 and LTI-01, and multiple candidates in preclinical development focused on fibrosis indications.

On October 31, 2023, Aileron acquired Lung Therapeutics, Inc. (“Lung Therapeutics” or “Lung”) pursuant to an Agreement and Plan of Merger, dated October 31, 2023 (the “Lung Acquisition Agreement”), by and among the Company, AT Merger Sub I, Inc., a Delaware corporation and its wholly owned subsidiary (“First Merger Sub”), AT Merger Sub II, LLC, a Delaware limited liability company and its wholly owned subsidiary (“Second Merger Sub”), and Lung. Pursuant to the Lung Acquisition Agreement, First Merger Sub merged with and into Lung, pursuant to which Lung was the surviving entity and became its wholly owned subsidiary (the “First Merger”). Immediately following the First Merger, Lung merged with and into Second Merger Sub, pursuant to which Second Merger Sub was the surviving entity (such merger, together with the First Merger, the “Lung Acquisition”). Lung was incorporated on November 13, 2012 under the laws of the state of Texas. Following the Lung Acquisition, the Company shifted its operating disease focus to advancing a pipeline of first-in-class medicines to address significant unmet medical needs in orphan pulmonary and fibrosis indications with the potential to greatly improve patient outcomes over currently available treatments. Following expiration of the operating lease agreement to rent an office space for its corporate headquarters in Austin, Texas, on March 31, 2024, the Company has been operating virtually and expects to continue to do so for the foreseeable future (see Note 15 for further details).

The Company is subject to risks and uncertainties common to clinical-stage companies in the biotechnology industry, including, but not limited to the risk that the Company never achieves profitability, the need for substantial additional financing, the risk of relying on third parties, risks of clinical trial failures, dependence on key personnel, protection of proprietary technology, and compliance with government regulations. The Company’s lead product candidate, LTI-03, is being developed for the treatment of Idiopathic Pulmonary Fibrosis (“IPF”) and has completed a healthy volunteer Phase 1a clinical trial. The Company has also conducted a Phase 1b clinical trial of LTI-03 in patients diagnosed with IPF and, in November 2024, the Company announced positive topline data from Cohort 2 of the Phase 1b clinical trial. The Company’s second product candidate, LTI-01, is in development for loculated pleural effusion (“LPE”). The Company has completed Phase 1b and Phase 2a clinical trials in LPE patients. In June 2024, the Company decided to temporarily delay clinical development of LTI-01 in an effort to focus the Company’s resources on clinical development of LTI-03 and until additional funds are raised.

Liquidity and Going Concern

In accordance with Accounting Standards Update (“ASU”) No. 2014-15, Disclosures of Uncertainties about an Entity’s Ability to Continue as a Going Concern (Subtopic 205-40), the Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the accompanying consolidated financial statements are issued. This evaluation initially does not take into consideration the potential mitigating effect of management’s plans that have not been fully implemented as of the date the condensed consolidated financial statements are issued. When substantial doubt exists, management evaluates whether the mitigating effect of its plans sufficiently alleviates substantial doubt about the company’s ability to continue as a going concern. The mitigating effect of management’s plans, however, is only considered if both (1) it is probable that the plans will be effectively implemented within one year after the date that the consolidated financial statements are issued, and (2) it is probable that the plans, when implemented, will mitigate the relevant conditions or events that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the date that the financial statements are issued. Generally, to be considered probable of being effectively implemented, the plans must have been approved before the date that the consolidated financial statements are issued.

The Company’s condensed consolidated financial statements have been prepared assuming that the Company will continue to operate as a going concern, which contemplates the continuity of operations, realization of assets and the satisfaction of liabilities in the ordinary course of business. Through September 30, 2024, the Company has financed its operations primarily through $145,467 in net proceeds from sales of common stock and warrants, $131,211 from sales of preferred stock prior to its initial public offering (“IPO”), $34,910 from a collaboration agreement in 2010, $17,536 in net proceeds in connection with a private placement following the Lung Acquisition in 2023, and $17,675 in net proceeds in connection with an underwritten offering of the Company's common stock and accompanying warrants to purchase common stock in May 2024. As of September 30, 2024, the Company had $17,652 in cash and cash equivalents.

In May 2024, Aileron completed an underwritten follow-on public offering (the “Offering”), pursuant to which the Company issued and sold 4,273,505 shares of the Company’s common stock, par value $0.001 per share (the “Offering Shares”) and accompanying warrants (the “Offering Warrants”) to purchase 4,273,505 shares of common stock (the “Offering Warrant Shares”). All of the Offering Shares and Offering Warrants were sold by the Company. Each Offering Share was offered and sold together with an accompanying

Offering Warrant at a combined offering price of $4.68, and the underwriter purchased each Offering Share with an accompanying Offering Warrant from the Company at a combined price of $4.35. Net proceeds from the Offering were $17,675, after deducting underwriting discounts and commissions and offering expenses, and excluding any proceeds that may be received from exercise of the Offering Warrants.

On July 26, 2024, the Company entered into an Equity Distribution Agreement with Citizens JMP Securities, LLC (“Citizens JMP”), as agent and/or principal, under which the Company may offer and sell up to $50,000 of shares of its common stock from time to time through or to Citizens JMP. Sales of common stock through or to Citizens JMP may be made by any method that is deemed an “at the market” offering as defined in Rule 415(a)(4) under the Securities Act of 1933, as amended, including sales made directly on or through the Nasdaq Capital Market. There have been no sales on the "at the market" offering through September 30, 2024.

Management believes that, based on the Company’s current operating plan, the Company’s cash and cash equivalents of $17,652 as of September 30, 2024 will not be sufficient to enable the Company to fund its operating expenses and capital expenditure requirements for at least twelve months from the date of issuance of these condensed consolidated financial statements, which raises substantial doubt about our ability to continue as a going concern.

Since its inception, the Company has not generated any revenue from product sales and has never generated an operating profit. The Company has incurred significant losses on an aggregate basis. The Company’s net losses were $21,902 and $8,393 for the nine months ended September 30, 2024 and 2023, respectively. As of September 30, 2024, the Company had an accumulated deficit of $310,419. These losses have resulted primarily from costs incurred in connection with research and development activities, licensing and patent investment and general and administrative costs associated with the Company’s operations. Management expects to continue to incur operating losses for the foreseeable future. The Company expects to finance its operations primarily through utilization of its current financial resources and through the sale of additional equity or debt financings, collaborations, licensing arrangements or other sources.

The Company plans to address these conditions by, among other things, raising additional funds through equity or debt financings, strategic collaborations, licensing arrangements or other sources. However, there is no assurance that such funding will be available to the Company, will be obtained on terms favorable to the Company or will provide the Company with sufficient funds to meet its objectives. The Company’s funding estimates are based on assumptions that may prove to be wrong, and the Company could use its available capital resources sooner than it currently expects. If additional funds are not available, the Company could be forced to delay, reduce or eliminate its research and development programs or future commercialization efforts and its business could be materially harmed. The Company’s future viability is dependent on its ability to raise additional capital, enter into a financing, consummate a successful acquisition, merger, business combination, or a sale of assets or other transaction. If the Company becomes unable to continue as a going concern, it may have to liquidate its assets and the values it receives for its assets in liquidation or dissolution could be significantly lower than the values reflected in its consolidated financial statements. The financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Accrued Expenses and Other Current Liabilities

9 Months Ended

Sep. 30, 2024

Payables and Accruals [Abstract]

Accrued Expenses and Other Current Liabilities

8. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following:


	September 30, 2024		December 31, 2023
External research and development services	$	2,207	$	1,110
Payroll and payroll-related costs		1,453		1,178
Professional fees		847		653
Other		73		206
Total accrued expenses and other current liabilities	$	4,580	$	3,147

Summary of Significant Accounting Policies

9 Months Ended

Sep. 30, 2024

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and as amended by ASUs of the Financial Accounting Standards Board (“FASB”).

Principles of Consolidation

The accompanying condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Lung Therapeutics, LLC, Lung Therapeutics Australia Pty Ltd, and Lung Therapeutics Limited. Lung Therapeutics Limited is currently inactive. All intercompany balances and transactions have been eliminated in consolidation.

Use of Estimates

The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, the accrual for research and development expenses, the prepaid research and development expenses, and the value of stock-based compensation. Estimates are

periodically reviewed in light of changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates.

Unaudited Interim Financial Information

The accompanying unaudited condensed consolidated financial statements as of September 30, 2024 and for the nine months ended September 30, 2024 and 2023 have been prepared by the Company pursuant to the rules and regulations of the United States Securities and Exchange Commission (the “SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. However, the Company believes that the disclosures are adequate to make the information presented not misleading. These financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023 that was filed with the SEC on April 15, 2024.

The condensed consolidated financial statements have been prepared on the same basis as the audited consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of September 30, 2024, the results of its operations for the three and nine months ended September 30, 2024 and 2023 and its cash flows for the nine months ended September 30, 2024 and 2023. The financial data and other information disclosed in these notes related to the three and nine months ended September 30, 2024 and 2023 are unaudited. The results for the nine months ended September 30, 2024 are not necessarily indicative of results to be expected for the year ending December 31, 2024, any other interim periods, or any future year or period. The accompanying balance sheet as of December 31, 2023 has been derived from the Company’s audited consolidated financial statements for the year ended December 31, 2023 included in the Company’s Annual Report on Form 10-K.

The Company’s significant accounting policies are described in Note 2 to the consolidated financial statements included in the Annual Report on Form 10-K for the year ended December 31, 2023.

Concentration of Credit Risk and of Significant Suppliers

Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. Periodically, the Company maintains balances in operating accounts above federally insured limits. The Company deposits its cash in financial institutions that it believes have high credit quality. The Company has not experienced any losses on such accounts and does not believe it is exposed to any significant credit risk on cash and cash equivalents.

The Company is dependent on third-party manufacturers to supply products for research and development activities of its programs, including preclinical and clinical testing. In particular, the Company relies on a small number of manufacturers to supply it with its requirements for the active pharmaceutical ingredients and formulated drugs related to these programs. These programs could have been adversely affected by a significant interruption in the supply of active pharmaceutical ingredients and formulated drugs.

Accounting Pronouncements Not Yet Adopted

In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income (Topic 220): Disaggregation of Income Statement Expenses (“ASU 2024-03”), to enhance the transparency and decision usefulness of financial information presented in the income statement by requiring disaggregated information about certain income statement expense line items. This ASU is effective for annual periods beginning after December 15, 2026, and interim reporting periods beginning after December 15, 2027. The Company has not evaluated the impact of this ASU on its consolidated financial statements and related disclosures.

In March 2024, the FASB issued ASU 2024-02, Codification Improvements—Amendments to Remove References to the Concepts Statements, that contains amendments to the Codification that remove references to various FASB Concepts Statements. This effort facilitates Codification updates for technical corrections such as conforming amendments, clarifications to guidance, simplifications to wording or the structure of guidance, and other minor improvements. The amendments are effective for public business entities for fiscal years beginning after December 15, 2024, with early adoption permitted. Early application of the amendments in this ASU is permitted for all entities, for any fiscal year or interim period for which financial statements have not yet been issued (or made available for issuance). If an entity adopts the amendments in an interim period, it must adopt them as of the beginning of the fiscal year that includes that interim period. The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.

In March 2024, the FASB issued ASU 2024-01, Compensation—Stock Compensation (Topic 718): Scope Application of Profits Interest and Similar Awards, to improve GAAP by adding an illustrative example that includes four fact patterns to demonstrate how an entity should apply the scope guidance in paragraph 718-10-15-3 to determine whether a profits interest award should be accounted for in accordance with Topic 718, Compensation—Stock Compensation. For public business entities, the amendments in this ASU are effective for annual periods beginning after December 15, 2024, and interim periods within those annual periods. Early adoption is permitted for both interim and annual financial statements that have not yet been issued or made available for issuance. If an entity

adopts the amendments in an interim period, it should adopt them as of the beginning of the annual period that includes that interim period. The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, to enhance the transparency and decision usefulness of income tax disclosures by requiring disaggregated information about an entity’s effective tax rate reconciliation, as well as information on taxes paid. This ASU is effective for annual periods beginning after December 15, 2024. Interim disclosures are not impacted by this update. The Company has not evaluated the impact of these amendments on its annual disclosures.

In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280): Improvements to Segment Disclosures, to improve reportable segment disclosure requirements, primarily through enhanced disclosures about significant segment expenses. This ASU is effective for fiscal years beginning after December 15, 2023 and interim periods within fiscal years beginning after December 15, 2024. The Company is evaluating the impact of the new requirements, effective for its 2024 consolidated financial statements, to determine the level of disclosure of segment expenses.