2 unchanged sentences
The term “disclosure controls and procedures”, as defined in Rules 13a-15(e) and 15d-15(e) under the Exchange Act, refers to controls and procedures that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC’s rules and forms.
−Removed: Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure.
+Added: Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information required to be disclosed by a
+Added: company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the company’s management, including its principal executive and principal financial officers, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure.
In designing and evaluating our disclosure controls and procedures, management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives.
−Removed: In addition, the design of disclosure controls and procedures must reflect the fact that there
−Removed: are resource constraints and that management is required to apply judgment in evaluating the benefits of possible controls and procedures relative to their costs.
+Added: In addition, the design of disclosure controls and procedures must reflect the fact that there are resource constraints and that management is required to apply judgment in evaluating the benefits of possible controls and procedures relative to their costs.
Evaluation of Disclosure Controls and Procedures
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A material weakness is a deficiency, or combination of deficiencies, in internal control over financial reporting such that there is a possibility that a material misstatement of our financial statements will not be prevented or detected on a timely basis.
−Removed: Management identified material weaknesses related to the (i) lack of sufficient accounting and supervisory personnel to maintain appropriate segregation of duties relating to user access of the financial accounting system and who have the appropriate level of technical accounting experience and training, (ii) lack of evidence over reviews of account reconciliations and supporting schedules, and (iii) lack of adequate procedures and controls to ensure that accurate financial statements could have been prepared and reviewed on a timely basis for annual reporting purposes.
−Removed: In the year ended December 31, 2023, management identified material weaknesses related to the accounting for the Lung Acquisition, including a lack of sufficient precision in the performance of reviews supporting the purchase price
−Removed: allocation accounting, and a lack of timely oversight over third-party specialists and the reports they produced to support the accounting for the Lung Acquisition.
+Added: We identified the following material weaknesses in internal control over financial reporting:
+Added: (i) lack of sufficient
+Added: accounting and supervisory personnel who have the appropriate level of technical accounting experience and training, and (ii) lack of adequate procedures and controls to ensure that accurate financial statements could have been prepared and reviewed on a timely basis for annual reporting purposes.
Management’s Plan to Remediate the Material Weaknesses
−Removed: We have implemented and are continuing to implement procedures to remediate these material weaknesses, including the hiring of a Controller with the requisite supervisory background and knowledge in financial reporting, integration into one accounting system, engaging third party accounting specialists and building a more streamlined process in order to prepare and review financial information, however, our control environment needs improvement, and as a result we may be exposed to errors.
−Removed: Our remediation plan also includes the hiring of additional accounting employees and/or consultants with the specific technical accounting experience necessary to assist with complex, non-routine transactions and to support the timely completion of financial close procedures, the implementation of robust processes, and to assist with the preparation of financial statements and our compliance with SEC reporting obligations.
−Removed: Management has engaged a third-party to assist in evaluating and documenting the design and operating effectiveness of our internal control over financial reporting, and their work is ongoing.
−Removed: With the help of third-party consultants, we have nearly completed the integration of the acquired systems from the Lung Acquisition into our financial and accounting systems.
−Removed: Additionally, we intend to develop and implement consistent accounting policies and internal control procedures and provide additional training to our accounting and financial reporting personnel.
The below are actions that we have taken to date to remediate the above-mentioned material weaknesses:
• Enhanced the execution of our risk assessment activities by evaluating whether the design of our internal controls appropriately addresses changes in the business (including changes to people, processes and systems) that could impact our system of internal controls.
−Removed: • Substantially completed the integration of the acquired systems from the Lung Acquisition into our financial and accounting systems to allow for systematic segregation of duties, and to enhance the accurate and timely preparation and review of financial statements and supporting schedules.
+Added: • Completed the integration of the acquired systems from the Lung Acquisition into our financial and accounting systems to allow for systematic segregation of duties, and to enhance the accurate and timely preparation and review of financial statements and supporting schedules.
• Engaged a third-party to assist in assessing the design and implementation of controls and develop remediation plans for identified control gaps related to our timely preparation and review of account reconciliations, financial statements and supporting schedules.
• Reported regularly to the audit committee on the progress and results of the remediation plan, including the identification, status and resolution of internal control deficiencies.
+Added: • Continued to reassess staffing and add additional resources, as required, with the requisite technical accounting experience and training, to further allow for segregation of duties and to support our system of internal control.
In addition to implementing and executing the aforementioned activities, the following activities are expected to be completed in fiscal year 2026:
−Removed: • Continue to reassess staffing and add additional resources, as required, with the requisite technical accounting experience and training, to further allow for segregation of duties and to support our system of internal control.
• Implement remediation plans for identified control design and implementation gaps.
−Removed: • Define user roles within our ERP system to ensure proper segregation of duties within our accounting systems.
+Added: • Continue to act upon the enhancements to our internal controls that we implemented in 2025.
• Perform testing of operating effectiveness of identified controls over financial reporting including IT General Controls.
1 unchanged sentence
The material weaknesses will not be considered remediated until management completes the design and implementation of the measures described above and the controls operate for a sufficient period of time and management has concluded, through testing, that these controls are effective.
−Removed: Management believes that the remediation measures described above will be implemented in a manner such that the controls can be tested, and the
−Removed: identified material weaknesses can be determined to be remediated, however, no assurance can be made that such remediation will occur or that additional material weaknesses will not be identified.
+Added: Management believes that the remediation measures described above will be implemented in a manner such that the controls can be tested, and the identified material weaknesses can be determined to be remediated, however, no assurance can be made that such remediation will occur or that additional material weaknesses will not be identified.
Changes in Internal Control Over Financial Reporting
−Removed: Except for the above noted and previously reported material weaknesses and the related ongoing remediation activities described above, no change in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) has occurred during the year ended December 31, 2024 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.
+Added: In connection with our December 31, 2024 10-K, a material weakness in our internal control over financial reporting was identified relating to segregation of duties within our financial accounting system and lack of reviews of account reconciliation and supporting schedules.
+Added: Management implemented measures designed to ensure that the control deficiencies related to the material weaknesses were remediated, such that the controls are designed, implemented and operating effectively.
+Added: The remediation actions included hiring of additional accounting personnel which allowed for proper segregation of duties within the financial accounting system and the implementation of internal controls related to the account reconciliation process.
+Added: Other than the changes to remediate the material weaknesses and the related ongoing remediation activities described above, no change in our internal control over financial reporting (as defined in Rules 13a-15(f) and 15d-15(f) under the Exchange Act) has occurred during the year
+Added: ended December 31, 2025 that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.
Other Information
3 unchanged sentences
Directors, Executive Off icers and Corporate Governance
−Removed: The information required by this Item 10 will be included in our definitive proxy statement to be filed with the Securities and Exchange Commission, or SEC, with respect to our 2025 Annual Meeting of Stockholders, which is expected to be filed no later than 120 days after the end of our last fiscal year ended December 31, 2024 and is incorporated herein by reference.
+Added: The information required by this Item 10 will be included in our definitive proxy statement to be filed with the Securities and Exchange Commission, or the SEC, with respect to our 2026 Annual Meeting of Stockholders, which is expected to be filed no later than 120 days after the end of our last fiscal year ended December 31, 2025 and is incorporated herein by reference.
We have adopted a Code of Business Conduct and Ethics that applies to our officers, including our principal executive, financial and accounting officers, and our directors and employees.
32 unchanged sentences
Form of Warrant to Purchase Common Stock issued pursuant to the Stock and Warrant Purchase Agreement
−Removed: 2006 Stock Incentive Plan, as amended
−Removed: Form of Incentive Stock Option Agreement under 2006 Stock Incentive Plan
−Removed: Form of Nonstatutory Stock Option Agreement under 2006 Stock Incentive Plan
2016 Stock Incentive Plan
10 unchanged sentences
Form of Director and Officer Indemnification Agreement
−Removed: Amended and Restated Employment Agreement, dated as of September 6, 2018, between the Registrant and Manuel C.
−Removed: Alves Aivado, M.D., Ph.D.
−Removed: Severance Agreement, dated as of September 6, 2018, between the Registrant and Manuel C.
−Removed: Alves Aivado, M.D., Ph.D.
−Removed: Form of Warrant to Purchase Common Stock
−Removed: Registration Rights Agreement, dated as of September 21, 2020, by and between the Company and Lincoln Park Capital Fund, LLC
−Removed: Equity Distribution Agreement, dated July 26, 2024, by and between Aileron Therapeutics, Inc.
−Removed: and Citizens JMP Securities, LLC
Consulting Agreement, dated as of April 15, 2023, between the Registrant and D.
22 unchanged sentences
Lung Therapeutics, Inc.2013 Long-Term Incentive Plan, as amended
−Removed: Aileron Insider Trading Policy
+Added: Rein Insider Trading Policy
Subsidiaries of Rein Therapeutics, Inc.
+Added: Consent of CBIZ CPAs PC, independent registered public accounting firm
Consent of Marcum LLP, independent registered public accounting firm
5 unchanged sentences
Section 1350, as Adopted Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
−Removed: Aileron Therapeutics, Inc.
+Added: Rein Therapeutics, Inc.
Compensation Recovery Policy
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Rein Therapeutics, Inc.
−Removed: April 7, 2025
+Added: March 26, 2026
/s/ Brian Windsor, Ph.D.
2 unchanged sentences
(principal executive officer)
−Removed: POWER OF ATTORNEY
−Removed: Each person whose signature appears below constitutes and appoints Brian Windsor, Ph.D.
−Removed: and Timothy M.
−Removed: Cunningham, each or any of them, such person's true and lawful attorney-in-fact and agent with full power of substitution and resubstitution for such person and in such person's name, place and stead, in any and all capacities, to sign any and all amendments to this report on Form 10-K, and to file the same with all exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing necessary or desirable to be done in and about the premises, as fully to all intents and purposes as such person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or any of them or his or their substitute or substitutes, may lawfully do or cause to be done by virtue hereof.
Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, this Report has been signed below by the following persons on behalf of the Registrant in the capacities and on the dates indicated.
1 unchanged sentence
President, Chief Executive Officer and Director (principal executive officer)
−Removed: April 7, 2025
+Added: March 26, 2026
Brian Windsor, Ph.D.
2 unchanged sentences
(principal financial officer and principal accounting officer)
−Removed: April 7, 2025
+Added: March 26, 2026
Von Rickenbach
Chairman of the Board of Directors
−Removed: April 7, 2025
+Added: March 26, 2026
Von Rickenbach
−Removed: /s/ Manuel C.
−Removed: April 7, 2025
/s/ Reinhard J.
Ambros, Ph.D.
−Removed: April 7, 2025
+Added: March 26, 2026
Ambros, Ph.D.
/s/ William C.
−Removed: April 7, 2025
+Added: March 26, 2026
/s/ Alan Musso
−Removed: April 7, 2025
+Added: March 26, 2026
INDEX TO CONSOLIDATED FINANCIAL STATEMENTS
Report of Independent Registered Public Accounting Firm (PCAOB ID 199 )
+Added: Report of Independent Registered Public Accounting Firm (PCAOB ID 688)
Consolidated Balance Sheets as of December 31, 2025 and 2024
3 unchanged sentences
Notes to Consolidated Financial Statements
−Removed: Report of Inde pendent Registered Public Accounting Firm
−Removed: To the Shareholders and Board of Directors of
+Added: Report of Independent Registered Public Accounting Firm
+Added: To the Stockholders and Board of Directors of
Rein Therapeutics Inc.
Opinion on the Financial Statements
−Removed: We have audited the accompanying consolidated balance sheets of Rein Therapeutics Inc.
−Removed: (the “Company”) as of December 31, 2024 and 2023, the related consolidated statements of operations and comprehensive loss, changes in convertible preferred stock and stockholders’ equity and cash flows for each of the two years in the period ended December 31, 2024, and the related notes (collectively referred to as the “financial statements”).
−Removed: In our opinion, based on our audits, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2024 and 2023, and the results of its operations and its cash flows for each of the two years in the period ended December 31, 2024, in conformity with accounting principles generally accepted in the United States of America .
+Added: We have audited the accompanying consolidated balance sheet of Rein Therapeutics Inc.
+Added: (the “Company”) as of December 31, 2025, the related consolidated statements of operations and comprehensive loss, changes in convertible preferred stock and stockholders’ equity and cash flows for the year ended December 31, 2025, and the related notes (collectively referred to as the “financial statements”).
+Added: In our opinion, based on our audit, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2025, and the results of its operations and its cash flows for the year ended December 31, 2025, in conformity with accounting principles generally accepted in the United States of America.
Explanatory Paragraph – Going Concern
The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern.
−Removed: As more fully described in Note 1, the Company has incurred significant losses and expects to continue to incur operating losses and needs to raise additional funds to meet its obligations and sustain its operations.
+Added: As more fully described in Note 1, the Company has a significant working capital deficiency, has incurred significant losses and needs to raise additional funds to meet its obligations and sustain its operations.
These conditions raise substantial doubt about the Company's ability to continue as a going concern.
3 unchanged sentences
These financial statements are the responsibility of the Company's management.
−Removed: Our responsibility is to express an opinion on the Company's financial statements based on our audits.
+Added: Our responsibility is to express an opinion on the Company's financial statements based on our audit.
We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) ("PCAOB") and are required to be independent with respect to the Company in accordance with the U.S.
federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.
−Removed: We conducted our audits in accordance with the standards of the PCAOB.
−Removed: Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.
+Added: We conducted our audit in accordance with the standards of the PCAOB.
+Added: Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.
The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting.
−Removed: As part of our audits we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting.
+Added: As part of our audit we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting.
Accordingly, we express no such opinion.
−Removed: Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks.
+Added: Our audit included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks.
Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements.
−Removed: Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements.
−Removed: We believe that our audits provide a reasonable basis for our opinion.
+Added: Our audit also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements.
+Added: We believe that our audit provides a reasonable basis for our opinion.
Critical Audit Matters
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Critical Audit Matter Description
−Removed: As described in Notes 1 and 6 to the consolidated financial statements, the Company’s consolidated balances of Goodwill and In-process Research and Development (“IPR&D”) indefinite-lived intangible assets were $6.3 million and $42.2 million, respectively, as of December 31, 2024.
+Added: As described in Note 5 to the consolidated financial statements, the Company’s consolidated balances of Goodwill and In-process Research and Development (“IPR&D”) indefinite-lived intangible assets were $6.3 million and $13.5 million, respectively, as of December 31, 2025.
The Company reviews goodwill for impairment at least annually or more frequently if events or circumstances indicate the carrying value at the reporting unit level might exceed its fair value.
17 unchanged sentences
and (iv) evaluating the reasonableness of the significant assumptions to the models, including the discount rate applied to future cash flows.
+Added: /s/ CBIZ CPAs P.C.
+Added: CBIZ CPAs P.C.
+Added: We have served as the Company’s auditor since 2024 (such date takes into account the acquisition of the attest business of Marcum llp by CBIZ CPAs P.C.
+Added: effective November 1, 2024).
+Added: March 26, 2026
+Added: Report of Independent Registered Public Accounting Firm
+Added: To the Shareholders and Board of Directors of
+Added: Rein Therapeutics Inc.
+Added: Opinion on the Financial Statements
+Added: We have audited the accompanying consolidated balance sheet of Rein Therapeutics Inc.
+Added: (the “Company”) as of December 31, 2024, the related consolidated statements of operations and comprehensive loss, changes in convertible preferred stock and stockholders’ equity and cash flows for the year ended December 31, 2024, and the related notes (collectively referred to as the “financial statements”).
+Added: In our opinion, based on our audit, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2024, and the results of its operations and its cash flows for the year ended December 31, 2024, in conformity with accounting principles generally accepted in the United States of America.
+Added: Explanatory Paragraph – Going Concern
+Added: The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern.
+Added: As more fully described in Note 1, the Company has incurred significant losses and expects to continue to incur operating losses and needs to raise additional funds to meet its obligations and sustain its operations.
+Added: These conditions raise substantial doubt about the Company's ability to continue as a going concern.
+Added: Management's plans in regard to these matters are also described in Note 1.
+Added: The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.
+Added: Basis for Opinion
+Added: These financial statements are the responsibility of the Company's management.
+Added: Our responsibility is to express an opinion on the Company's financial statements based on our audit.
+Added: We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) ("PCAOB") and are required to be independent with respect to the Company in accordance with the U.S.
+Added: federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.
+Added: We conducted our audit in accordance with the standards of the PCAOB.
+Added: Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud.
+Added: The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting.
+Added: As part of our audit we are required to obtain an understanding of internal control over financial reporting but not for the purpose of expressing an opinion on the effectiveness of the Company's internal control over financial reporting.
+Added: Accordingly, we express no such opinion.
+Added: Our audit included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks.
+Added: Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements.
+Added: Our audit also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements.
+Added: We believe that our audit provides a reasonable basis for our opinion.
/s/ Marcum llp
−Removed: We have served as the Company’s auditor since 2024.
−Removed: New York, New York
+Added: We have served as the Company’s auditor from 2024 to 2025.
April 7, 2025
5 unchanged sentences
Prepaid expenses and other current assets
−Removed: Restricted cash
−Removed: Operating lease, right-of-use asset, current portion
Total current assets
6 unchanged sentences
Accrued expenses and other current liabilities
−Removed: Operating lease liabilities, current portion
Total current liabilities
4 unchanged sentences
Convertible preferred stock, $ 0.001 par value, 5,000,000 shares authorized at December 31, 2025 and at December 31, 2024;
−Removed: 24,610 shares issued and 12,232 shares outstanding at December 31, 2024 and 24,610 shares issued and outstanding at December 31, 2023
+Added: 24,610 shares issued and 12,232 shares outstanding at December 31, 2025 and at December 31, 2024
Stockholders’ equity:
15 unchanged sentences
Impairment loss on intangible assets
−Removed: Restructuring and other costs
Total operating expenses
6 unchanged sentences
Other comprehensive gain (loss):
−Removed: Unrealized gain on investments, net of tax of $ 0
+Added: Unrealized (loss) gain on investments, net of tax of $ 0
Foreign currency translation adjustments
−Removed: Total other comprehensive gain (loss)
+Added: Total other comprehensive (loss) gain
Total comprehensive loss
8 unchanged sentences
Balances at December 31, 2023
−Removed: Issuance of common stock in connection with business acquisition
−Removed: Issuance of Series X preferred stock in connection with business acquisition
−Removed: Stock options assumed in connection with business acquisition
−Removed: Common stock warrants assumed in connection with business acquisition
−Removed: Issuance of Series X preferred stock in connection with the Financing, net of issuance costs of $ 855
−Removed: Issuance of common stock warrants in connection with the Financing, net of issuance costs of $ 38
−Removed: Stock-based compensation expense
−Removed: Unrealized gain on short-term investments
−Removed: Foreign currency translation adjustments
−Removed: Balances at December 31, 2023
Issuance of common stock in connection with conversion of Series X non-voting convertible preferred stock
5 unchanged sentences
Unrealized gain on investments
+Added: Balances at December 31, 2024
+Added: Issuance of common stock for Pre-Paid Advances
+Added: Issuance of common stock for commitment fee
+Added: Issuance of common stock in connection with “at the market” offerings
+Added: Issuance of warrants
+Added: Issuance of common stock in connection with Warrant Exercises
+Added: Warrant Exchanges
+Added: Stock-based compensation expense
+Added: Exercises of stock options
+Added: Vesting of restricted stock units
+Added: Common Stock to be issued upon Warrant Exercises
+Added: Unrealized gain on investments
+Added: Foreign currency translation adjustments
Balance at December 31, 2025
6 unchanged sentences
Adjustments to reconcile net loss to net cash used in operating activities:
+Added: Commitment fee related to Pre-Paid Advance agreement
+Added: Original issue discount related to Pre-Paid Advance agreement
Depreciation and amortization expense
−Removed: Net amortization of premiums and discounts on investments
Stock-based compensation expense
−Removed: Gain on sale of property and equipment
Impairment loss on intangible assets
−Removed: Loss on disposition of property and equipment
Changes in operating assets and liabilities:
6 unchanged sentences
Net cash used in operating activities
−Removed: Cash flows from investing activities:
−Removed: Proceeds from sale of property and equipment
−Removed: Proceeds from sales or maturities of investments
−Removed: Acquisition, net of cash acquired
−Removed: Net cash provided by investing activities
Cash flows from financing activities:
Proceeds from issuance of common stock, net of offering costs
+Added: Proceeds from Pre-Paid Advances, net of discounts
Proceeds from issuance of common stock in connection with stock option exercises
+Added: Proceeds from issuance of common stock in connection with Warrant Exercises, net of costs
Proceeds from issuance of warrants, net of offering costs
−Removed: Proceeds from the PIPE Financing
+Added: Proceeds from Warrant Exchanges, net of offering costs
+Added: Proceeds from warrant exercises with common stock subscribed
Net cash provided by financing activities
Effect of exchange rate changes on cash and cash equivalents
−Removed: Net (decrease) increase in cash, cash equivalents and restricted cash
−Removed: Cash, cash equivalents and restricted cash at beginning of year
−Removed: Cash, cash equivalents and restricted cash at end of year
+Added: Net decrease in cash and cash equivalents
+Added: Cash and cash equivalents at beginning of year
Cash and cash equivalents at end of year
−Removed: Restricted cash at end of year
−Removed: Cash, cash equivalents and restricted cash at end of year
+Added: Cash and cash equivalents at end of year
+Added: Cash and cash equivalents at end of year
Supplemental disclosure of non-cash investing and financing activities:
+Added: Unrealized (loss) gain on short-term investments
+Added: Foreign currency translation adjustments
+Added: Issuance of common stock for Pre-Paid Advances and interest accrual
Conversion of Series X non-voting convertible preferred stock into common stock shares
−Removed: Unrealized gain on short-term investments
−Removed: Fair value of common shares issued in the Lung Acquisition
−Removed: Fair value of Series X Preferred Stock issued in the Lung Acquisition
−Removed: Fair value of options assumed in the Lung Acquisition
−Removed: Fair value of warrants assumed in the Lung Acquisition
The accompanying notes are an integral part of these consolidated financial statements.
3 unchanged sentences
Nature of the Business
−Removed: On January 10, 2025, Aileron Therapeutics, Inc., or Aileron, amended its Restated Certificate of Incorporation, as amended, to effect a change of the Company’s name from “Aileron Therapeutics, Inc.” to “Rein Therapeutics, Inc.” (“Rein” or the “Company”).
−Removed: The name change became effective at 4:00 p.m.
−Removed: Eastern Time on January 10, 2025.
−Removed: The Board of Directors of the Company, or the Board, approved the name change pursuant to Section 242 of the General Corporation Law of the State of Delaware.
−Removed: The name change does not affect the rights of the Company’s stockholders, and there were no other changes to the Certificate of Incorporation.
−Removed: A copy of the certificate of amendment to the Restated Certificate of Incorporation filed with the Secretary of State of the State of Delaware to affect the name change was filed with the Securities and Exchange Commission, or the SEC.
−Removed: In connection with the name change, the Board also approved an amendment and restatement of the Company’s Amended and Restated Bylaws solely to reflect the name change (as amended and restated, the “Amended and Restated Bylaws”) effective as of January 10, 2025.
−Removed: A copy of the Amended and Restated Bylaws was filed with the SEC.
−Removed: Aileron Therapeutics, Inc.
−Removed: was a clinical stage chemoprotection oncology company.
−Removed: Aileron's product candidate, ALRN-6924, was a MDM2/MDMX dual inhibitor that leverages its proprietary peptide drug technology.
−Removed: In February 2023, Aileron decided to terminate further development of ALRN-6924.
−Removed: On October 31, 2024, Aileron entered into an exclusive option agreement with Advancium Health Network, or Advancium, for the sale of ALRN-6924.
+Added: On January 10, 2025, Aileron Therapeutics, Inc., or Aileron, amended its Restated Certificate of Incorporation, as amended, to effect a change of the Company’s name from “Aileron Therapeutics, Inc.” to “Rein Therapeutics, Inc.”, or Rein, or the Company.
+Added: Prior to the Lung Acquisition (as defined below), the Company was a clinical stage chemoprotection oncology company.
+Added: The Company’s product candidate, ALRN-6924, was a MDM2/MDMX dual inhibitor that leverages its proprietary peptide drug technology.
+Added: In February 2023, the Company decided to terminate further development of ALRN-6924.
+Added: On October 31, 2024, the Company entered into an exclusive option agreement with Advancium Health Network, or Advancium, for the sale of ALRN-6924.
+Added: In July 2025, the option agreement was terminated.
+Added: In August 2025, the Company entered into a letter agreement with Rients LLC, or Rients, for Rients to evaluate the legacy ALRN-6924 compound, or the Compound Asset.
+Added: During the term of the letter agreement, Rients shall pay the Company for all fees and expenses incurred by the Company to maintain the Compound Asset.
The Company is a clinical stage biopharmaceutical company focused on developing novel therapies for the treatment of fibrosis indications with no approved or limited effective treatments.
−Removed: 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.
+Added: The Company currently has one product candidate in clinical development, LTI-03.
+Added: Development of another product candidate, LTI-01, as well as multiple candidates in preclinical development focused on fibrosis indications were postponed for an indefinite period due to insufficient financing as disclosed below.
On October 31, 2023, the Company acquired Lung Therapeutics, Inc., or Lung Therapeutics or Lung, pursuant to an Agreement and Plan of Merger, dated October 31, 2023, or the Lung Acquisition Agreement, by and among the Company, AT Merger Sub I, Inc., a Delaware corporation and its wholly owned subsidiary, or the First Merger Sub, AT Merger Sub II, LLC, a Delaware limited liability company and its wholly owned subsidiary, or the Second Merger Sub, and Lung.
−Removed: 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, or the First Merger.
−Removed: 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.
−Removed: Lung was incorporated on November 13, 2012 under the laws of the state of Texas.
Its principal offices are in Austin, Texas.
2 unchanged sentences
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.
−Removed: The Company’s lead product candidate, LTI-03, is being developed for the treatment of Idiopathic Pulmonary Fibrosis, or IPF, and has completed a healthy volunteer Phase 1a clinical trial and has conducted a Phase 1b clinical trial in IPF patients.
−Removed: The Company’s second product candidate, LTI-01, is in development for loculated pleural effusion, or LPE.
+Added: The Company’s lead product candidate, LTI-03, is being developed for the treatment of Idiopathic Pulmonary Fibrosis, or IPF, and has been evaluated in a healthy volunteer Phase 1a clinical trial and in a Phase 1b clinical trial in IPF patients.
+Added: A Phase 2 multi-center, randomized, double-blind, and placebo-controlled study evaluating the safety, tolerability, and efficacy of LTI-03 in patients with IPF will enroll up to 120 IPF patients with interim topline data expected in the second half of 2026.
+Added: The Company’s second product candidate, LTI-01, was in development for loculated pleural effusion, or LPE.
The Company has completed Phase 1b and Phase 2a clinical trials in LPE patients.
+Added: In June 2024, the Company decided to temporarily delay clinical development of LTI-01 in an effort to focus its resources on clinical development of LTI-03 and until additional funds are raised.
+Added: In the fourth quarter of 2024, the Company determined that the temporary delay of further clinical development of LTI-01 may not be a short-term measure.
+Added: In the fourth quarter of 2025, the Company decided to pause development activities related to LTI-01 for an indefinite period.
+Added: The timing and likelihood of resuming development are uncertain and contingent on the Compamy’s ability to obtain additional financing and the future success of LTI-03.
+Added: In May 2025, the Company initiated screening and recruitment of patients in the RENEW Phase 2 clinical trial of LTI-03.
+Added: The RENEW trial is a Phase 2 multi-center, randomized, double-blind, placebo-controlled study evaluating the safety, tolerability, and efficacy of LTI-03 patients with IPF.
+Added: In addition, the trial is designed to assess the activity of inhaled dry powder LTI-03 across multiple biomarkers and to measure lung function, lung imaging markers of fibrosis, and the potential for healthy tissue regeneration.
+Added: The trial is designed to enroll approximately 120 patients diagnosed with IPF within 5 years of screening, who may be receiving standard of care antifibrotic therapy, across up to 50 sites globally, including sites in the U.S., UK, Germany, Australia and Poland.
+Added: Patients will be randomized into two blinded placebo-controlled cohorts that will run concurrently.
+Added: Patients in the low dose cohort will receive 2.5 mg
+Added: of either LTI-03 or placebo administered twice daily, or BID, for a total dose of 5 mg/day, while participants in the high dose cohort will receive 5 mg BID for a total dose of 10 mg/day.
+Added: The primary endpoint is the incidence of treatment-emergent adverse events from Day 1 through Week 24.
+Added: The key secondary endpoint is the efficacy of LTI-03 measured through forced vital capacity, percent predicted FVC and high-resolution computer tomography, in collaboration with Qureight Ltd.
+Added: Patients will undergo a 28-day screening period prior to being randomized and entering the 24-week treatment period, with a four-week follow-up.
+Added: In October 2025, the Company received authorization from the European Medicines Agency, or the EMA, to initiate its Phase 2 RENEW trial of its lead candidate, LTI-03, for the treatment of IPF at sites in Germany and Poland.
+Added: The Company had previously received regulatory clearance from the UK’s Medicines and Healthcare products Regulatory Agency, or the MHRA.
+Added: In January 2026, the Company received orphan drug designation from the EMA for LTI-03.
+Added: As of the date of this Annual Report, the Company activated sites and is enrolling patients in the U.S.
+Added: and is seeking to activate additional sites, enroll patients and initiate the RENEW trial throughout the U.S., UK, Europe and other jurisdictions.
+Added: In March 2026, the Company dosed its first patient in the RENEW Phase 2 clinical trial of LTI-03.
+Added: The Company expects to report initial interim topline data on some proportion of patients in the fourth quarter of 2026.
Liquidity and Going Concern
6 unchanged sentences
The Company’s 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.
−Removed: Through December 31, 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, or 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.
+Added: Through December 31, 2025, the Company has financed its operations primarily through $ 145,467 in net proceeds from sales of common stock and warrants, $ 2,201 in net proceeds from sales of common stock under its “at the market” offering programs, $ 131,211 from sales of preferred stock prior to its initial public offering, or 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, $ 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, $ 5,082 in net proceeds from the April 2025 Transactions (as defined below) an d $ 2,850 in net proceeds from the Yorkville Transactions described below.
As of December 31, 2025, the Company had $ 3,215 in cash and cash equivalents.
1 unchanged sentence
All of the Offering Shares and Offering Warrants were sold by the Company.
−Removed: 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 .
+Added: Each Offering Share was offered and sold together with an accompanying Offering Warrant at a combined public offering price of $ 4.68 , and the underwriter purchased each Offering Share with an accompanying Offering Warrant from the Company, after the underwriting discount, 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.
−Removed: As of December 31, 2024, none of the Offering Warrants had been exercised.
−Removed: On July 26, 2024, the Company entered into an Equity Distribution Agreement with Citizens JMP Securities, LLC, or 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.
−Removed: 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.
−Removed: There have been no sales on the “at the market” offering through December 31, 2024.
−Removed: Refer to Note 17 for sales on the “at the market” offering subsequent to the consolidated balance sheet date.
−Removed: Management believes that, based on the Company’s current operating plan, the Company’s cash and cash equivalents of $ 12,865 as of December 31, 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 consolidated financial statements, which raises substantial doubt about our ability to continue as a going concern.
+Added: The Offering Warrants to purchase 890,138 shares of common stock were exercised in April 2025 as part of April 2025 Transactions (as defined below).
+Added: As of December 31, 2025, Offering Warrants to purchase 3,388,707 shares of common stock remained outstanding.
+Added: In April 2025, the Company entered into privately negotiated letter agreements with certain holders of the PIPE Warrants, as described in Note 3, and certain holders of the Offering Warrants, who agreed to exercise for cash the PIPE Warrants and the Offering Warrants, or the Warrant Exercises as further discussed in Note 8.
+Added: The total gross proceeds for the Warrant Exercises were $ 1,679 .
+Added: Also in April 2025, the Company entered into privately negotiated letter agreements with additional holders of the PIPE Warrants who, in exchange for pre-funded warrants, or the Exchange Pre-Funded Warrants, surrendered PIPE Warrants to the Company for cancellation and made an aggregate cash payment into which the Exchange Pre-Funded Warrants are exercisable, or the Warrant Exchanges as further discussed in Note 8.
+Added: The total gross proceeds for the Warrant Exchanges were $ 3,101 .
+Added: In addition, an entity affiliated with Bios Partners, or the Bios Purchaser, purchased additional pre-funded warrants in a private placement, or the Placement Pre-Funded Warrants, pursuant to a subscription agreement underlying the Placement Pre-Funded Warrants, or the Private Placement.
+Added: Total gross proceeds for the Private Placement were $ 500 .
+Added: The Warrant Exercises, Warrant Exchanges and Private Placement are collectively referred to as the April 2025 Transactions.
+Added: On May 15, 2025, the Company entered into an “at the market offering” agreement, or the Wainwright Sales Agreement, with H.C.
+Added: Wainwright & Co., LLC, or H.C.
+Added: Wainwright, as agent and/or principal, pursuant to which the Company could offer and sell shares of its common stock having an aggregate offering price of up to $ 13,702 from time to time through or to H.C.
+Added: Wainwright by any method permitted that is deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended.
+Added: As of December 31, 2025, the Company had issued and sold 999,967 shares of common st ock pursuant to the Wainwright Sales Agreement for total net proceeds of $ 1,489 , after deducting transaction fees of $ 52 paid by the Company .
+Added: In July 2025, in connection with the Yorkville Transactions, the Company reduced the aggregat e offering price of the shares of common stock that could be offered and sold under the Wainwright Sales Agreement to $ 8,067 .
+Added: Prior to entering into the Wainwright Sales Agreement, in May 2025, the Company terminated the equity distribution agreement, dated July 26, 2024, or the Equity Distribution Agreement, with Citizens JMP Securities, LLC, or Citizens JMP, as agent and/or principal, under which the Company could offer and sell up to $ 50,000 of shares of its common stock from time to time through or to Citizens JMP by any method that was deemed an “at the market” offering as defined in Rule 415(a)(4) under the Securities Act of 1933, as amended.
+Added: In January 2025, the Company issued and sold 317,772 shares of common stock pursuant to the Equity Distribution Agreement for total net proceeds of $ 712 , after deducting transaction fees of $ 22 paid by the Company.
+Added: The Company did no t issue or sell any other shares of common stock pursuant to the Equity Distribution Agreement during the year ended December 31, 2025.
+Added: The Company did no t sell any shares of common stock pursuant to the Equity Distribution Agreement during the year ended December 31, 2024.
+Added: In July 2025, the Company entered into a Pre-Paid Advance Agreement, or the PPA, an d a Standby Equity Purchase Agreement, or the SEPA, with YA II PN, Ltd., a Cayman Islands exempt limited partnership, or Yorkville.
+Added: The PPA and the SEPA are collectively referred to as the Yorkville Transactions.
+Added: In accordance with the terms of the PPA, the Company may request pre-paid advances of up to $ 6,000 from Yorkville (each, a “Pre-Paid Advance”) over a 12-month period, subject to certain limitations and conditions set forth in the PPA.
+Added: Each Pre-Paid Advance will be purchased by Yorkville at 95 % of the face amount of the Pre-Paid Advance.
+Added: At any time there is an outstanding balance under any Pre-Paid Advances, Yorkville may provide written notice requiring the Company to issue and sell shares of its common stock to Yorkville, which shall be offset against and reduce the amounts outstanding under the Pre‑Paid Advances.
+Added: An initial Pre-Paid Advance of $ 1,000 was purchased on July 29, 2025 by Yorkville, or the First Advance, for net proceeds of $ 950 .
+Added: O n September 8, 2025, Yorkville purchased a second Pre-Paid Advance, or the Second Advance, of $ 1,000 , for which the Company received net proceeds of $ 950 .
+Added: On October 23, 2025, Yorkville purchased a third Pre-Paid Advance, or the Third Advance, of $ 1,000 , for which the Company received net proceeds of $ 950 .
+Added: As of December 31, 2025, Yorkville has converted the entire initial Pre‑Paid Advance, in the aggregate amount of $ 1,007 of principal and accrued interest, into 953,765 shares of the Company’s common stock, at a weighted average price per share of approximately $ 1.056 , converted the Second Advance, in the aggregate amount of $ 1,004 of principal and accrued interest, into 927,107 shares of the Company’s common stock, at a weighted average price per share of approximately $ 1.082 , and converted the Third Advance, in the aggregate amount of $ 1,001 of principal and accrued interest, into 846,290 shares of the Company’s common stock, at a weighted average price per share of approximately $ 1.183 .
+Added: Separately, under the SEPA, the Company may sell up to $ 15,000 of its common stock to Yorkville over a 36-month term.
+Added: The Company has the sole discretion to initiate such sales, subject to volume and pricing limitations.
+Added: In connection with entry into the SEPA, the Company paid Yorkville a $ 300 commitment fee through the issuance of 213,099 shares of common stock and paid $ 25 in structuring and legal fees.
+Added: As of the date of this report, the Company has not elected to sell any shares of common stock to Yorkville under the SEPA.
+Added: In December 2025, the Company elected to terminate the PPA and SEPA.
+Added: Management believes that, based on the Company’s current operating plan, the Company’s cash and cash equivalents of $ 3,215 as of December 31, 2025, together with the proceeds received by the Company pursuant to the securities purchase agreements it entered into in January 2026 and February 2026, will be sufficient to enable the Company to fund its planned operating expense and capital expenditure requirements into the second quarter of 2026.
+Added: The funds are not sufficient to enable the Company to complete the Phase 2 RENEW clinical trial of LTI-03.
+Added: The Company’s estimate as to how long it expects its existing cash and cash equivalents to be able to continue to fund its operations is based on assumptions that may prove to be wrong, and the Company could use its available capital resources sooner than it currently expects.
+Added: In addition, the Company’s cash and cash equivalents 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 consolidated financial statements, which raises substantial doubt about the Company’s 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.
3 unchanged sentences
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.
−Removed: Management expects to continue to incur operating losses for the foreseeable future.
+Added: The Company 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.
−Removed: 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.
+Added: The Company plans to seek to raise 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.
1 unchanged sentence
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.
−Removed: 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.
+Added: 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 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.
11 unchanged sentences
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.
−Removed: Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the accrual for research and development expenses, the prepaid research and development expenses, valuation of intangibles and goodwill, the valuation of warrants, and the value of stock-based compensation.
+Added: Significant estimates and assumptions reflected in these consolidated financial statements include, but are not limited to, the accrual for research and development expenses, the prepaid research and development expenses, valuation of intangibles and goodwill, the valuation of warrants, and the value of stock-based
+Added: compensation.
Estimates are periodically reviewed in light of changes in circumstances, facts and experience.
15 unchanged sentences
The FDIC provides insurance coverage up to applicable limits for deposits held in participating financial institutions.
+Added: At various times, the Company has deposits in these financial institutions in excess of the amount insured by the FDIC.
The Company considers all short-term, highly liquid investments with original maturities of 90 days or less at the acquisition date to be cash equivalents.
14 unchanged sentences
The carrying values of the Company’s accounts payable and accrued expenses approximate their fair value due to the short-term nature of these liabilities.
−Removed: The Company accounts for leases under ASC Topic 842, Leases , or ASC 842.
−Removed: Under ASC 842, at inception of a contract, the Company determines whether an arrangement is or contains a lease.
−Removed: For all leases, the Company determines the classification as either operating leases or financing leases.
−Removed: Operating leases are included in operating lease right-of-use assets and operating lease liabilities in the Company’s consolidated balance sheets.
−Removed: Lease recognition occurs at the commencement date and lease liability amounts are based on the present value of lease payments over the lease term.
−Removed: The lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option.
−Removed: If a lease does not provide information to determine an
−Removed: implicit interest rate, the Company uses its incremental borrowing rate in determining the present value of lease payments.
−Removed: Right-of-use, or ROU, assets represent the Company’s right to use an underlying asset for the lease term, and lease liabilities represent the Company’s obligation to make lease payments under the lease.
−Removed: ROU assets also include any lease payments made prior to the commencement date and exclude lease incentives received.
−Removed: Operating lease payments are expensed using the straight-line method as a general and administrative expense over the lease term.
−Removed: The depreciable life of assets and leasehold improvements are limited by the expected lease term unless there is a transfer of title or purchase option reasonably certain of exercise.
−Removed: The Company has elected to apply the practical short-term expedient to leases with a lease term of 12 months or less, which does not subject the leases to capitalization.
−Removed: The Company had an operating lease of office space.
−Removed: The lease expired March 31, 2024 , and the Company did not renew the lease.
−Removed: Following expiration of the lease, the Company is operating virtually, and expects to do so for the foreseeable future.
Goodwill and Indefinite-Lived Intangible Assets
4 unchanged sentences
Simplifying the Test for Goodwill Impairment .
−Removed: The Company’s goodwill and intangible assets are deductible for tax purposes.
+Added: The Company’s goodwill and intangible assets are not deductible for tax purposes.
Impairment of Long-Lived Assets
16 unchanged sentences
The Company has classified its Series X convertible preferred stock, referred to as Series X Preferred Stock, as temporary equity in the accompanying consolidated balance sheets due to terms that allow for redemption of the shares in cash upon certain change in control events that are outside of the Company’s control, including sale or transfer of control of the Company as holders of the Series X Preferred Stock could cause redemption of the shares in these situations.
−Removed: The Company did not accrete the carrying values of the preferred stock to the redemption values since a liquidation event was not considered probable as of December 31, 2024.
+Added: The Company did not accrete the carrying values of the preferred stock to the redemption values since a liquidation event was not considered probable as of December 31, 2025 or December 31, 2024.
Subsequent adjustments of the carrying values to the ultimate redemption values will be made only when it becomes probable that such a liquidation event will occur .
27 unchanged sentences
The risk-free interest rate is determined by reference to the U.S.
−Removed: Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award.
+Added: Treasury yield curve in effect at the time of grant of the award for time periods
+Added: approximately equal to the expected term of the award.
Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future.
The quoted market price of the Company’s common stock is used to estimate the fair value of the stock-based awards at grant date.
−Removed: Restructuring and Other Costs
−Removed: The Company incurred restructuring-related charges of $ 928 for the year ended December 31, 2023 relating to the Company's decision to terminate its Phase 1b breast cancer trial of ALRN-6924 and further development of ALRN-6924.
−Removed: One-time termination costs were in connection with the reduction-in-workforce, including severance, benefits, and related costs.
−Removed: The Company paid all restructuring-related charges during the year ended December 31, 2023.
The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the financial statements or in the Company’s tax returns.
35 unchanged sentences
For purpose of this calculation, Series X non-voting convertible preferred stock, outstanding options and warrants to purchase common stock are considered potentially dilutive securities.
−Removed: Acquisition Accounting
−Removed: The fair value of the consideration exchanged in a business combination is allocated to tangible assets and identifiable intangible assets acquired and liabilities assumed at acquisition date fair value.
−Removed: Goodwill is measured as the excess of the consideration transferred over the net fair value of identifiable assets acquired and liabilities assumed.
−Removed: The accounting for an acquisition involves a considerable amount of judgment and estimation.
−Removed: Cost, income, market or a combination of approaches may be used to establish the fair value of consideration exchanged, assets acquired, and liabilities assumed, depending on the nature of those items.
−Removed: The valuation approach is determined in accordance with generally accepted valuation methods.
−Removed: Key areas of estimation and judgment may include the selection of valuation approaches, cost of capital, market characteristics, cost structure, impacts of synergies, and estimates of terminal value, among other factors.
−Removed: While the Company uses estimates and assumptions as part of the purchase price allocation process to estimate the fair value of assets acquired and liabilities assumed, estimates are inherently uncertain and subject to refinement.
−Removed: During the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the assets acquired and liabilities assumed, with a corresponding offset to goodwill, to the extent that adjustments are identified to the preliminary purchase price allocation.
−Removed: Upon conclusion of the measurement period, or final determination of the value of the assets acquired and liabilities assumed, whichever comes first, any subsequent adjustments are recorded to results of operations.
Recently Adopted Accounting Pronouncements
+Added: In November 2024, the FASB issued ASU 2024-04, Debt—Debt with Conversion and Other Options (Subtopic 470-20):
+Added: Induced Conversions of Convertible Debt Instruments , to improve relevance and consistency in application of the induced conversion guidance in Subtopic 470-20.
+Added: The ASU 2024-04 is effective for all entities for annual reporting periods beginning after December 15, 2025, and interim reporting periods within those annual reporting periods.
+Added: Early adoption is permitted as of the beginning of the annual reporting period for all entities that have adopted the amendments in ASU 2020-06, Debt—Debt with Conversion and Other Options and Derivatives and Hedging—Contracts in Entity's Own Equity:
+Added: Accounting for Convertible Instruments and Contracts in an Entity's Own Equity.
+Added: The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.
+Added: 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.
+Added: 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.
+Added: Adoption of this guidance did not have a material impact on the Company’s consolidated financial statements.
+Added: In March 2024, the FASB issued ASU 2024-01, Compensation—Stock Compensation (Topic 718):
+Added: 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 .
+Added: For public business entities, the amendments in this ASU are effective for annual periods beginning after December 15, 2024.
+Added: Adoption of this guidance did no t have a material impact on the Company’s consolidated financial statements.
+Added: In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740):
+Added: 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.
+Added: This ASU is effective for annual periods beginning after December 15, 2024 .
+Added: The Company has adopted this ASU prospectively for the year ended December 31, 2025 and prepared the required disclosures, refer to Note 14.
In November 2023, the FASB issued ASU 2023-07, Segment Reporting (Topic 280):
5 unchanged sentences
Accounting Pronouncements Not Yet Adopted
+Added: In December 2025, the FASB issued ASU 2025-12, Codification Improvements .
+Added: The amendments include technical corrections, clarifications, and minor improvements to various Topics within the FASB ASC.
+Added: The ASU is effective for annual reporting periods beginning after December 15, 2026, and interim periods within those annual reporting periods, with early adoption permitted.
+Added: Adoption of this guidance is not expected to have a material impact on the Company’s consolidated financial statements.
+Added: In December 2025, the FASB issued ASU 2025-11, Interim Reporting (Topic 270):
+Added: Narrow-Scope Improvements .
+Added: The amendments clarify the application of interim reporting guidance, including when Topic 270 applies, and improve the consistency and usefulness of interim disclosures.
+Added: The amendments are effective for interim reporting periods within annual reporting periods beginning after December 15, 2027, for public business entities and for interim reporting periods within annual reporting periods beginning after December 15, 2028, for entities other than public business entities.
+Added: Early adoption is permitted for all entities.
+Added: The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.
In January 2025, the FASB issued ASU 2025-01, Income Statement—Reporting Comprehensive Income—Expense Disaggregation Disclosures (Subtopic 220-40):
3 unchanged sentences
The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.
−Removed: In November 2024, the FASB issued ASU 2024-04, Debt—Debt with Conversion and Other Options (Subtopic 470-20):
−Removed: Induced Conversions of Convertible Debt Instruments , to improve the relevance and consistency in application of the induced conversion guidance in Subtopic 470-20.
−Removed: The ASU 2024-04 is effective for all entities for annual reporting periods beginning after December 15, 2025, and interim reporting periods within those annual reporting periods.
−Removed: Early adoption is permitted as of the beginning of the annual reporting period for all entities that have adopted the amendments in ASU 2020-06, Debt—Debt with Conversion and Other Options and Derivatives and Hedging—Contracts in Entity’s Own Equity:
−Removed: Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity.
−Removed: The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.
In November 2024, the FASB issued ASU 2024-03, Income Statement—Reporting Comprehensive Income (Topic 220):
3 unchanged sentences
The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.
−Removed: 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.
−Removed: 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
−Removed: improvements.
−Removed: The amendments are effective for public business entities for fiscal years beginning after December 15, 2024, with early adoption permitted.
−Removed: 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).
−Removed: 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.
−Removed: The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.
−Removed: In March 2024, the FASB issued ASU 2024-01, Compensation—Stock Compensation (Topic 718):
−Removed: 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 .
−Removed: 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.
−Removed: Early adoption is permitted for both interim and annual financial statements that have not yet been issued or made available for issuance.
−Removed: 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.
−Removed: The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.
−Removed: In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740):
−Removed: 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.
−Removed: This ASU is effective for annual periods beginning after December 15, 2024.
−Removed: The Company is currently assessing the effect of this ASU on its consolidated financial statements and related disclosures.
−Removed: Business Acquisition
−Removed: On October 31, 2023, the Company acquired 100 % of Lung, pursuant to the Lung Acquisition Agreement.
−Removed: At the closing of the Lung Acquisition, the Company 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, or the Series X Preferred Stock, (excluding 238 fractional shares from the total 20,141 shares pursuant to the Lung Acquisition Agreement).
−Removed: Each share of Series X Preferred Stock is convertible into 1,000 shares of common stock.
−Removed: The Company paid $ 290 cash in lieu of fractional shares of both common stock and Series X Preferred Stock.
−Removed: In addition, the Company 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.
−Removed: Immediately following the closing of the Lung Acquisition, on October 31, 2023, the Company entered into a Stock and Warrant Purchase Agreement, or the Purchase Agreement, with a group of accredited investors, pursuant to which the Company issued and sold (i) an aggregate of 4,707 shares of Series X Preferred Stock, and (ii) warrants, or the PIPE Warrants, to purchase up to an aggregate of 2,353,500 shares of the Company’s common stock, or 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”).
−Removed: The PIPE Financing closed on November 2, 2023.
−Removed: Each share of Series X Preferred Stock is convertible into 1,000 shares of common stock.
−Removed: The net proceeds from the Financing of approximately $ 17,536 are expected to be used to advance Rein’s clinical development pipeline, business development activities, working capital and other general corporate purposes.
−Removed: The Lung Acquisition was accounted for under the acquisition method of accounting under ASC 805, Business Combinations .
−Removed: 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.
−Removed: 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
−Removed: to the former owners of the acquiree (except for the measurement of share-based payment awards).
−Removed: The total purchase price consideration consisted of the following:
−Removed: Fair value of common stock issued to Lung stockholders
−Removed: Fair value of Series X Preferred Stock issued to Lung stockholders
−Removed: Cash in lieu of fractional shares
−Removed: Fair value of the options assumed
−Removed: Fair value of the warrants assumed
−Removed: Total purchase price consideration
−Removed: 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.
−Removed: The following table presents the allocation of the purchase price to the estimated fair values of the assets acquired and liabilities assumed as of the Lung Acquisition date:
−Removed: Assets acquired:
−Removed: Cash and cash equivalents
−Removed: Prepaid expenses and other current assets
−Removed: Property and equipment, net
−Removed: Operating right-of-use assets
−Removed: Indefinite-lived intangible assets
−Removed: Liabilities assumed:
−Removed: Accounts Payable
−Removed: Accrued expenses and other current liabilities
−Removed: Operating lease liabilities, current
−Removed: Convertible notes payable
−Removed: Deferred tax liability
−Removed: Net assets acquired
−Removed: At the 2023 annual meeting of stockholders, or 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.
−Removed: 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.
Fair Value of Financial Assets
7 unchanged sentences
Money market funds
+Added: Treasury bills
During the years ended December 31, 2025 and 2024, there were no transfers between levels.
5 unchanged sentences
Goodwill and Indefinite-Lived Intangible Assets
−Removed: In the fourth quarter of 2024, the Company determined that the temporary delay of further clinical development of LTI-01 until additional funds are raised may not be a short-term measure.
+Added: Indefinite-lived intangible assets and goodwill are tested for impairment at least annually.
The assessment of recoverability and impairment was performed at the individual indefinite-lived intangible asset level.
−Removed: The Company concluded that the fair value of the LTI-01 was less than its carrying value and recognized an impairment loss for this asset of approximately $ 37,000 .
+Added: The Company incurred impairment loss on indefinite-lived intangible assets of $ 28,700 and $ 37,000 for the years ended December 31, 2025 and 2024, respectively, in connection with funding constraints that are causing the delay in further clinical development of LTI-01 and other preclinical programs until additional funds are raised.
+Added: In the fourth quarter of 2025, the Company decided to pause development activities related to LTI-01 for an indefinite period and focus on the development of LTI-03.
+Added: The timing and likelihood of resuming development of LTI-01 are uncertain and contingent on the Company's ability to obtain additional financing and the future success of LTI-03.
+Added: Therefore, the Company wrote off the total carrying value of the LTI-01 asset and other preclinical programs as of December 31, 2025, which resulted in an impairment loss of $ 28,700 for the year ended December 31, 2025.
This impairment charge is classified within impairment loss on intangible assets in the consolidated statements of operations and comprehensive loss.
The fair value of intangible assets was determined using multi-period excess earning method and using Level 3 inputs, which included estimates of forecasted cash flows for each candidate.
−Removed: The Company performed an impairment assessment of its goodwill, both qualitatively and quantitatively, and concluded that the fair value of goodwill exceeds its carrying value and there were no qualitative factors that would have triggered impairment, therefore no goodwill impairment was recognized as of December 31, 2024.
+Added: There was no impairment loss recognized for the LTI-03 asset during the year ended December 31, 2025 .
+Added: The Company performed an impairment assessment of its goodwill, both qualitatively and quantitatively, and concluded that the fair value of goodwill exceeds its carrying value, therefore no goodwill impairment was recognized as of December 31, 2025.
The fair value of reporting unit was determined using the income approach with a reconciliation to market capitalization.
1 unchanged sentence
Indefinite-lived intangible assets
−Removed: Other assets consisted of the following:
−Removed: Non-current prepaid research and development
−Removed: Total other non-current assets
−Removed: The non-current prepaid research and development asset was fully expensed during the year ended December 31, 2024 due to the temporary delay of clinical development of LTI-01.
Accrued Expenses and Other Current Liabilities
6 unchanged sentences
The Company is authorized to issue 5,000,000 shares of preferred stock, par value $ 0.001 per share.
−Removed: As of December 31, 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.
−Removed: As of December 31, 2023, 24,610 shares of Series X Preferred Stock were issued and outstanding.
−Removed: 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.
−Removed: 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.
−Removed: Refer to Note 3 for more details on the PIPE Financing in connection with the Purchase Agreement.
−Removed: 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.
−Removed: Total gross proceeds of $ 18,429 , less $ 893 of issuance costs were allocated as follows:
−Removed: $ 16,795 to the Series X Preferred Stock and $ 741 to the PIPE Warrants.
−Removed: The Series X Preferred Stock and the PIPE Warrants issued in the PIPE Financing were recorded at par value of $ 0.001 .
−Removed: 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.
+Added: As of December 31, 2025 and December 31, 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
+Added: At the 2023 annual meeting of stockholders, or the 2023Annual 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, based upon 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, the Bios Entities (as defined below) provided notice to the Company and converted 421 shares of Series X Preferred Stock held by them into 421,000 shares of common stock.
−Removed: As of December 31, 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).
+Added: As of December 31, 2025 and December 31, 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 , or ASC 480, and determined that equity treatment was appropriate because the Series X Preferred Stock did not meet the definition of the liability instruments.
16 unchanged sentences
The Series X Preferred Stock shall be perpetual unless converted.
−Removed: 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
−Removed: of authorized shares of common stock of the Company from 45,000,000 to 100,000,000 shares.
−Removed: 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.
−Removed: The additional shares of common stock authorized by the Certificate of Amendment have rights identical to the Company’s currently outstanding common stock.
−Removed: As of December 31, 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.
−Removed: As of December 31, 2024, the Company had 21,666,012 shares of common stock issued and outstanding.
−Removed: As of December 31, 2023, the Company had 4,885,512 shares of common stock issued and outstanding.
+Added: As of December 31, 2025 and December 31, 2024, the Company was authorized to issue 100,000,000 shares of common stock, par value $ 0.001 per share.
+Added: As of December 31, 2025 and December 31, 2024, the Company had 27,550,222 and 21,666,012 shares of common stock issued and outstanding, respectively.
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, if any.
−Removed: As of December 31, 2024 and December 31, 2023, no dividends had been declared.
+Added: As of December 31, 2025 and 2024, 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
−Removed: 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.
−Removed: 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.
+Added: Wainwright Sales Agreement
+Added: On May 15, 2025, the Company entered into the Wainwright Sales Agreement with H.C.
+Added: Wainwright, as agent and/or principal, pursuant to which the Company could offer and sell shares of its common stock having an aggregate offering price of up to $ 13,702 from time to time through or to H.C.
+Added: Wainwright by any method permitted that is deemed to be an “at the market offering” as defined in Rule 415(a)(4) promulgated under the Securities Act of 1933, as amended.
+Added: As of December 31, 2025, the Company had issued and sold 999,967 shares of common stock pursuant to the Wainwright Sales Agreement for total net proceeds of $ 1,489 , after deducting transaction fees of $ 52 paid by the Company.
+Added: In July 2025, in connection with the Yorkville Transactions, the Company reduced the aggregate offering price of the shares of common stock that could be offered and sold under the Wainwright Sales Agreement to $ 8,067 .
+Added: Prior to entering into the Wainwright Sales Agreement, in May 2025, the Company terminated its “at the market offering” pursuant to the Equity Distribution Agreement with Citizens JMP.
+Added: Through May 2025, the Company issued and sold 317,772 shares of common stock pursuant to the Equity Distribution Agreement for total net proceeds of $ 712 , after deducting transaction fees of $ 22 paid by the Company.
+Added: The Company did not issue or sell any other shares of common stock pursuant to the Equity Distribution Agreement during the year ended December 31, 2025.
The Company did not sell any shares of common stock pursuant to the Equity Distribution Agreement during the year ended December 31, 2024.
−Removed: Refer to Note 18 for sales on the “at the market” offering subsequent to the consolidated balance sheet date.
−Removed: In May 2024, the Company completed the 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.
−Removed: All of the Offering Shares and Offering Warrants were sold by the Company.
−Removed: 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 .
−Removed: 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.
+Added: Warrant Exercises and Exchanges
+Added: On April 21, 2025, the Company entered into privately negotiated letter agreements with certain holders of its outstanding warrants issued on November 2, 2023, or the PIPE Warrants, and May 1, 2024, or the Offering Warrants.
+Added: Pursuant to these agreements, certain holders agreed to exercise the PIPE Warrants for an aggregate of 159,500 shares of the Company’s common stock and the Offering Warrants for an aggregate of 890,138 shares of common stock, at a reduced exercise price of $ 1.60 per share.
+Added: The original exercise prices were $ 4.89 per share for the PIPE Warrants and $ 4.68 per share for the Offering Warrants.
+Added: The exercise of the PIPE Warrants was completed on April 24, 2025, and the exercise of the Offering Warrants was completed in May 2025 (collectively, the “Warrant Exercises”).
+Added: The Company received total net proceeds of $ 1,595 from the Warrant Exercises.
+Added: Separately, in April 2025, the Company entered into agreements with additional holders of the PIPE Warrants who agreed to surrender warrants representing an aggregate of 1,939,000 shares of common stock for cancellation.
+Added: In exchange, these holders received pre-funded warrants (the “Exchange Pre-Funded Warrants”) exercisable for the same number of shares at an exercise price of $ 0.001 per share and paid $ 1.599 per share in cash by April 24, 2025 (the “Warrant Exchanges”).
+Added: The Company received total net proceeds of $ 2,984 from the Warrant Exchanges.
+Added: As part of the Warrant Exchanges, entities affiliated with Bios Equity Partners, LP (“Bios Partners”) surrendered PIPE Warrants representing an aggregate of 1,300,500 shares and provided the associated cash consideration of $ 2,079 for the issuance of Exchange Pre-Funded Warrants.
+Added: In addition, on April 21, 2025, an entity affiliated with Bios Partners agreed to purchase additional pre-funded warrants to acquire 312,695 shares of the Company’s common stock in a private placement at a price of $ 1.599 per share, resulting in total net proceeds of $ 481 (the “Bios Pre-Funded Warrants”).
+Added: The Exchange Pre-Funded Warrants and the Bios Pre-Funded Warrants are collectively referred to as the “Pre-Funded Warrants.”
+Added: The Company assessed the Pre-Funded Warrants for appropriate classification under U.S.
+Added: GAAP and determined that they 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 .
+Added: The Pre-Funded Warrants are indexed to the Company’s common stock and meet all other conditions for equity classification under ASC 480 and ASC 815.
+Added: Accordingly, the Pre-Funded Warrants are classified as equity and accounted for as a component of additional paid-in capital at the time of issuance.
+Added: The Pre-Funded Warrants were initially recognized at their fair value, calculated as the fair value of the underlying common stock less the exercise price of $ 0.001 per share.
+Added: The fair value of the common stock was determined based on the quoted market price of the Company’s common stock as of the issuance date.
+Added: The Pre-Funded Warrants will not be remeasured subsequent to initial recognition.
+Added: The repricing of the PIPE Warrants and the Offering Warrants and issuance of the Exchange Pre-Funded Warrants is considered a modification under the guidance of ASU 2021-04.
+Added: The modification is consistent with the “Equity Issuance” classification under that guidance as the reason for the modification was to induce the holder to cash exercise their warrants, resulting in the imminent exercise of the PIPE Warrants and the Offering Warrants, which raised equity capital and generated net proceeds for the Company of approximately $ 4,601 .
+Added: The total fair value of the consideration of the modification includes the incremental fair value of the PIPE Warrants and the Offering Warrants (determined by comparing the fair values immediately prior to and immediately after the modification) and the initial fair value of the PIPE Warrants and the Offering Warrants.
+Added: The fair values of the PIPE Warrants and the Offering Warrants were calculated using the Black-Scholes model.
+Added: The Company determined that the total fair value of the consideration related to the modification of PIPE Warrants and the Offering Warrants, including the initial fair value of the Exchange Pre-Funded Warrants was $ 4,757 .
+Added: The net effect of the modification in the amount of $ 490 , as well as the value of the replaced PIPE warrants of $ 1,385 and the fair value of the Exchange Pre-Funded Warrants of $ 5,652 were recorded in additional paid-in capital, as both the original warrants (the PIPE Warrants and the Offering Warrants) and the replacement instruments (the Exchange Pre-Funded Warrants) are equity-classified.
+Added: The Offering Warrants
+Added: In May 2024, the Company completed the Offering pursuant to which the Company issued and sold 4,273,505 shares of the Company’s common stock and accompanying the Offering Warrants to purchase 4,273,505 shares of common stock.
+Added: All of the Offering Shares and the Offering Warrants were sold by the Company.
+Added: Each Offering Share was offered and sold together with an accompanying Offering Warrant at a combined public offering price of $ 4.68 , and the underwriter purchased each Offering Share and accompanying Offering Warrant from the Company, after the underwriting discount, at a combined price of $ 4.35 .
+Added: Net proceeds from the Offering were approximately $ 17,675 ,
+Added: 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.
4 unchanged sentences
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.
−Removed: 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 , or ASC
+Added: The Company had 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.
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.
7 unchanged sentences
Exercise price
+Added: The Offering Warrants to purchase 884,798 shares of common stock were exercised in April 2025 as part of April 2025 Transactions.
+Added: As of December 31, 2025, Offering Warrants to purchase 3,388,707 shares of common stock remained outstanding.
+Added: Prepaid Purchase Agreement
+Added: On July 29, 2025, the Company entered into a PPA with Yorkville, pursuant to which the Company may request pre-paid advances of up to $ 6,000 from Yorkville over a 12-month period, subject to certain limitations and conditions set forth in the PPA.
+Added: Each Pre-Paid Advance is subject to the consent of Yorkville.
+Added: Interest shall accrue on the outstanding balance of any Pre-Paid Advance at an annual rate of 8 %, subject to an increase to 18 % upon events of default described in the PPA.
+Added: All Pre-Paid Advances are due and payable on the 12-month anniversary of their issuance.
+Added: At any time that there is an outstanding balance under any Pre-Paid Advances, Yorkville may provide written notice, or Purchase Notice, requiring the Company to issue and sell shares of its common stock to Yorkville, which shall be offset against and reduce the amounts outstanding under the Pre-Paid Advance.
+Added: The initial advance under the PPA of $ 1,000 was purchased on July 29, 2025, with net proceeds of $ 950 after a 5 % original issue discount, or OID.
+Added: On September 8, 2025, the Company entered into a second PPA with Yorkville for an additional $ 1,000 advance, with net proceeds of $ 950 after the 5 % OID.
+Added: On October 23, 2025, the Company entered into a third PPA with Yorkville for an additional $ 1,000 advance, with net proceeds of $ 950 after the 5 % OID.
+Added: The Company elected the fair value option under ASC 825, Financial Instruments , or ASC 825, to measure the PPAs at fair value, with changes in fair value recognized in earnings.
+Added: The initial fair value was determined to be equal to the net proceeds received ($ 950 per PPA), as this amount represented the cash consideration exchanged, consistent with ASC 825.
+Added: OID costs of $ 100 related to the first and second PPA were expensed as incurred in the third quarter of 2025, as required under the fair value option.
+Added: Additionally, the Company incurred legal costs of $ 118 which were expensed in the consolidated statements of operations and other comprehensive loss.
+Added: Under the terms of the PPAs, the Company issued shares of common stock to Yorkville in satisfaction of the advances.
+Added: The number of shares issued was determined based on the applicable purchase price per share equal to the lower of (a) 115 % of the daily volume weighted average price, or the VWAP, of the Company’s common stock on the last full trading day immediately prior to the date of such Pre‑Paid Advance and (b) 95 % of the lowest daily VWAP of the Company’s common stock during the seven consecutive trading days immediately preceding the date on which Yorkville provides the Purchase Notice to the Company, but in no event less than the floor price set forth in the PPA.
+Added: The carrying value of the PPA and accrued interest were reduced by the issuance of the shares.
+Added: Under the terms of the PPAs, through September 24, 2025, the Company issued an aggregate of 1,880,872 shares of common stock to Yorkville ( 953,765 shares under the first PPA through September 9, 2025, and 927,107 shares under the second PPA), based on the principal of $ 2,000 from the PPA and $ 11 of interest expense.
+Added: The shares were recorded at par value of $ 0.001 per share with the remainder credited to additional paid-in capital, or APIC.
+Added: On October 23, 2025, Yorkville purchased a third PPA of $ 1,000 , for which the Company received net proceeds of $ 950 .
+Added: The third PPA was converted to 846,290 shares of the Company’s common stock in October 2025, with no remaining outstanding balance.
+Added: The shares were recorded at par value of $ 0.001 per share with the remainder credited to APIC.
+Added: The initial, the second and the third PPAs were fully settled as of December 31, 2025, with no remaining outstanding balance.
+Added: Accordingly, the fair value of the liabilities at December 31, 2025, was $ 0 , and no adjustment for changes in fair value was required.
+Added: On December 11, 2025, the Company terminated the PPA.
+Added: Standby Equity Purchase Agreement
+Added: On July 29, 2025, the Company entered into a SEPA with Yorkville.
+Added: Under the SEPA, the Company has the right to sell to Yorkville up to $ 15.0 million of its common stock, par value $ 0.001 per share, subject to certain limitations and conditions set forth in the SEPA, from time to time, over a 36-month period.
+Added: The Company did not issue any SEPA Advances during the year ended December 31, 2025.
+Added: On December 11, 2025, the Company terminated the SEPA.
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, based upon then existing beneficial ownership limitations, 11,957 shares of Series X Preferred Stock were automatically converted into 11,957,000 shares of common stock.
−Removed: On October 31, 2023, Aileron acquired Lung.
−Removed: 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.
−Removed: Immediately following the closing of the Lung Acquisition, on October 31, 2023, the Company entered into the Purchase Agreement with a group of accredited investors, pursuant to which the Company 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 the Company ’s common stock.
−Removed: Refer to Note 3 for more details on the PIPE Financing in connection with the Purchase Agreement.
−Removed: 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.
−Removed: The PIPE Warrants are exercisable on or prior to May 2, 2027.
−Removed: 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.
−Removed: 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.
−Removed: 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 %;
−Removed: provided that any increase or decrease in such percentage will not be effective until 61 days after such notice is delivered to the Company.
−Removed: 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.
−Removed: 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.
−Removed: Accordingly, the PIPE Warrants are classified as equity and accounted for as a component of additional paid-in capital at the time of issuance.
−Removed: 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.
−Removed: As of December 31, 2024, 21,666,012 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.
−Removed: In addition, as of December 31, 2024, there were:
+Added: As of December 31, 2025, there were:
• 12,469,000 shares of common stock reserved for issuance upon conversion of the Series X Preferred Stock;
• 3,143,997 shares of common stock issuable upon the exercise of options under existing equity incentive plans;
−Removed: • 2,330,256 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;
+Added: • 420,000 shares of common stock issuable for vested but unsettled restricted stock units (Note 10);
+Added: • 1,914,194 and 7,500 shares of common stock reserved for issuance under the 2021 Plan (Note 10) and 2017 ESPP (Note 10), respectively, as well as any automatic increases in the number of shares of the common stock reserved under these plans;
• 6,621,839 shares of common stock reserved for issuance upon exercise of outstanding warrants.
−Removed: 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 .
+Added: 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 255,000 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 , (iii) warrants to purchase 3,388,707 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 , (iv) the Exchange Pre-Funded Warrants to purchase 1,939,000 shares of the Company's common stock, with an exercise price of $ 0.001 per share, which were issued and sold in the Warrant Exchanges as described above can be exercised at any time after their original issuance until such Exchange Pre-Funded Warrants are exercised in full, and (v) the Bios Pre-Funded Warrants to purchase 312,695 shares of the Company's common stock, with an exercise price of $ 0.001 per share, which were issued and sold in April 2025 as described above and can be exercised at any time after their original issuance until such Bios Pre-Funded Warrants are exercised in full.
Accordingly, as of December 31, 2025, out of the 100,000,000 shares of common stock presently authorized, 52,126,752 shares are issued and outstanding or reserved for issuance and 47,843,248 shares of common stock remain available for future issuance.
2 unchanged sentences
The Company provides an employer match, which is 100 % of employee deferrals up to the first 3 % of compensation for the period and 50 % of the next 2 % of compensation for the period and is immediately vested.
−Removed: The Company made matching contributions in the amount of $ 101 and $ 47 for the years ended December 31, 2024 and 2023, respectively.
+Added: The Company made matching contributions in the amo unt of $ 99 and $ 101 for the years ended December 31, 2025 and 2024, respectively.
Stock-Based Awards
2 unchanged sentences
The Company also assumed Lung’s 2013 Long-Term Incentive Plan, or the 2013 Plan, as a result of the Lung Acquisition.
−Removed: As of December 31, 2024, the Company had 6,693 shares issuable upon exercise of outstanding options under the 2006 Plan;
+Added: As of December 31, 2025, the Company had no 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 1,520,179 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 December 31, 2025.
+Added: 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.
+Added: 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.
Under the 2021 Plan, shares that are expired, terminated, surrendered or canceled without having been fully exercised will be available for future awards.
15 unchanged sentences
2013 Stock Incentive Plan
−Removed: The 2017 Plan was approved by the Company’s stockholders on June 16, 2017, and became effective on June 28, 2017.
−Removed: 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.
−Removed: The Company’s employees, officers, directors, consultants and advisors were eligible to receive awards under the 2017 Plan;
−Removed: however, incentive stock options could only be granted to employees.
−Removed: The 2017 Plan is administered by the Board or, at the discretion of the Board, by a committee of the Board.
−Removed: 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.
−Removed: 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 .
−Removed: 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.
−Removed: As of the effective date of the 2021 Plan, the Board determined to grant no further awards under the 2017 Plan.
−Removed: 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.
−Removed: 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.
−Removed: 2017 Employee Stock Purchase Plan
−Removed: On June 16, 2017, the Company’s stockholders approved the 2017 ESPP, which became effective on June 28, 2017.
−Removed: Under the 2017 ESPP, the number of shares of common stock that may be issued under the 2017 ESPP will
−Removed: 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.
−Removed: On January 1, 2023 and January 1, 2024, no additional shares were reserved for issuance under the 2017 ESPP pursuant to this provision.
−Removed: 7,500 shares remained available for future issuance under the 2017 ESPP as of December 31, 2024.
−Removed: 2013 Stock Incentive Plan
The Company assumed the 2013 Plan as a result of the Lung Acquisition.
9 unchanged sentences
Stock Option Valuation
−Removed: The assumptions that the Company used to determine the grant-date fair value of the stock options granted during the years ended December 31, 2024 and 2023 were as follows, presented on a weighted average basis:
+Added: The assumptions that the Company used to determine the grant-date fair value of the stock options granted to employees and directors during the year ended December 31, 2025 and 2024 were as follows, presented on a weighted average basis:
Year Ended December 31,
15 unchanged sentences
The weighted average grant-date fair value of stock options granted during the year ended December 31, 2024 was $ 2.46 .
−Removed: The aggregate fair value of stock options that vested during the years ended December 31, 2024 and 2023, was $ 1,520 and $ 1,191 , respectively.
+Added: The aggregate fair value of stock options that vested during the year ended December 31, 2025 and 2024, was $ 1,025 and $ 1,520 , 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.
−Removed: The aggregate intrinsic value of stock options exercised during the year ended December 31, 2024 was $ 354 .
−Removed: There were no stock options exercised during the year ended December 31, 2023.
+Added: The aggregate intrinsic value of stock options exercised during the year ended December 31, 2025 and 2024 was $ 18 and $ 354 , respectively.
+Added: Restricted Stock Units
+Added: The Company has granted restricted stock units with service-based vesting conditions.
+Added: Unvested shares of restricted common stock may not be sold or transferred by the holder.
+Added: A summary of the restricted stock unit activity during the year ended December 31, 2025 is as follows:
+Added: Restricted Stock Units
+Added: Weighted-Average Grant-Date Fair Value, $
+Added: Unvested - January 1, 2025
+Added: Unvested - December 31, 2025
+Added: The fair value of these vested restricted stock units was $ 1,194 at the grant date and all of the compensation expense was recognized in the year ended December 31, 2025.
+Added: On October 30, 2025, and December 2, 2025, the Company issued 300,000 and 280,000 shares of common stock for the restricted stock units granted and vested in August 2025, respectively.
+Added: As of December 31, 2025, there were 420,000 vested restricted stock units that were not issued.
Stock-Based Compensation
−Removed: The Company recorded stock-based compensation expense related to stock options in the following expense categories of its statements of operations and comprehensive loss:
+Added: The Company recorded stock-based compensation expense related to stock options and restricted stock units in the following expense categories of its statements of operations and comprehensive loss:
Year Ended December 31,
3 unchanged sentences
As of December 31, 2025, the Company had an aggregate of $ 1,475 of unrecognized stock-based compensation expense, which it expects to recognize over a weighted average period of 2.77 years.
−Removed: As of December 31, 2023, the Company had an aggregate of $ 1,702 of unrecognized stock-based compensation expense, which it expects to recognize over a weighted average period of 1.73 years.
−Removed: On March 11, 2024, the Company and Manuel C.
−Removed: 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, or CEO, of the Company, effective as of March 11, 2024.
−Removed: Aivado remains a member of the Company’s Board.
−Removed: Aivado’s resignation from the Company was not the result of any disagreement with the Company on any matter relating to its operations,
−Removed: policies or practices.
−Removed: As a non-employee director, following the separation date, Dr.
−Removed: Aivado will be compensated in accordance with the terms of the Company’s non-employee director compensation program.
−Removed: In addition, Dr.
−Removed: Aivado will continue to vest in all unvested stock option awards pursuant to the amended vesting terms.
−Removed: The resignation of Dr.
−Removed: 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 consolidated financial statements.
Net Loss per Share
3 unchanged sentences
Net loss per share attributable to common stockholders—basic and diluted
+Added: As part of the April 2025 Transactions, the Pre-Funded Warrants to purchase an aggregate of 2,251,695 shares of common stock at an exercise price of $ 0.001 per share are included within the denominator for basic net loss per share purposes and considered outstanding as of the date of issuance.
+Added: The 420,000 restricted stock units vested but not issued as of December 31, 2025, are included in earnings per share calculation as all conditions for issuance have been satisfied making the underlying shares contingently issuable and economically equivalent to outstanding shares.
The Company’s potential dilutive securities, which include stock options as of December 31, 2025 and 2024, 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.
6 unchanged sentences
Commitments and Contingencies
−Removed: Operating Leases
−Removed: 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.
−Removed: The lease expired March 31, 2024 , and the Company did not renew the lease.
−Removed: 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.
−Removed: As of December 31, 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.
+Added: As of December 31, 2025, the Company was not party to any legal proceedings and no material legal proceedings are currently pending or, to the Company’s knowledge, threatened.
Intellectual Property Licenses
15 unchanged sentences
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.
−Removed: The Company incurred $ 35 in license maintenance fees during the years ended December 31, 2024 and 2023, respectively.
+Added: The Company incurred $ 35 license maintenance fees in the year ended December 31, 2025, which was partially reimbursed by Advancium and the remaining is reimbursable by Rients.
+Added: The Company incurred $ 35 license maintenance fees in the year ended December 31, 2024.
Agreement with the University of Texas Health Science Center at Tyler
10 unchanged sentences
UTHSCT may also terminate the UTHSCT Agreement, but only if the Company breaches the terms of the agreement.
−Removed: The Company incurred $ 100 in a minimum royalty fee during the years ended December 31, 2024 and 2023, respectively.
+Added: The Company did not incur any expense under the UTHSCT Agreement in the years ended December 31, 2025 and 2024.
Agreement with the University of Texas at Austin
10 unchanged sentences
UT Austin may also terminate the UT Austin 6607 Agreement, but only if the Company breaches the terms of the agreement.
−Removed: The Company did not incur any expenses under the UT Austin 6607 Agreement during the years ended December 31, 2024 and 2023.
+Added: The Company did not incur any expense under the UT Austin 6607 Agreement in the years ended December 31, 2025 and 2024.
Agreement with Medical University of South Carolina
7 unchanged sentences
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.
−Removed: The Company incurred $ 25 in a minimum royalty fee during the year ended December 31, 2024.
−Removed: The Company did not incur any expenses under the MUSC Agreement during the year ended December 31, 2023.
+Added: The Company incur red $ 25 license fees in the years ended December 31, 2025 and 2024, respectively.
Agreement with Vivarta Therapeutics LLC
2 unchanged sentences
Pursuant to the Vivarta Agreement the Company 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 the Company 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.
−Removed: In consideration for the Vivarta Agreement, the Company agreed to grant Vivarta a warrant to purchase an aggregate of 75,000 shares of common stock of Lung 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.
+Added: In consideration for the Vivarta Agreement, the Company agreed to grant Vivarta a warrant to purchase an aggregate of 75,000 shares of common stock of Lung for $ 0.12 per share, to pay a license fee of $ 10,000 upon the
+Added: Vivarta Agreement effective date and $ 40,000 within 30 days of the receipt of a positive freedom to operate analysis from legal counsel.
The Company 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.
1 unchanged sentence
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.
−Removed: The Company did not incur any expenses under the Vivarta Agreement during the years ended December 31, 2024 and 2023.
+Added: The Company did not incur any expenses under the Vivarta Agreement in the years ended December 31, 2025 and 2024.
+Added: Master Services Agreement
+Added: In April 2025, the Company entered into a master services agreement with a third party Contract Research Organization, or CRO, under which the CRO has agreed to perform certain services in accordance with written work orders.
+Added: The work orders set forth the obligations of the parties with regard to conducting the clinical research study entitled “A Randomized, Double-Blind, Placebo-Controlled, Phase 2, Safety, Tolerability and Efficacy Study of Caveolin1-Scaffolding-Protein-Derived Peptide (LTI-03) in Patients with IPF”, under the Company’s Protocol LTI-03-2001.
+Added: Pursuant to the agreement, the Company had contracted for up to $ 17.0 million of master services.
+Added: In August 2025, this master services agreement was terminated with no future commitment for the Company.
+Added: Exclusive Option Agreement with Advancium
+Added: On October 31, 2024, the Company entered into an exclusive option agreement, or the Option Agreement, with Advancium Health Network, or Advancium, for the sale of ALRN-6924, a clinical stage oncology agent that the Company was developing prior to the Lung Acquisition (as defined below).
+Added: During the option period, Advancium intends to evaluate ALRN-6924 as a potential therapy for retinoblastoma.
+Added: Under the terms of the option agreement Advancium paid the Company a non-refundable fee of $ 0.1 million for the exclusive option to acquire ALRN-6924 and related assets.
+Added: 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.
+Added: In July 2025, the Option Agreement was terminated.
+Added: Letter Agreement with Rients
+Added: In August 2025, the Company entered into a letter agreement with Rients LLC, or Rients, for Rients to evaluate the legacy ALRN-6924 compound, or the Compound Asset.
+Added: During the term of the letter agreement, Rients shall pay the Company for all fees and expenses incurred by the Company to maintain the Compound Asset.
+Added: Project Addendum
+Added: In December 2025, the Company entered into a project addendum with a third party CRO for the purposes of setting forth the responsibilities and obligations of the parties in regards to conducting a certain clinical research program entitled “A Phase 2, Randomized, Double-Blind, Placebo-Controlled Study of the Safety, Tolerability and Efficacy of Caveolin-1-Scaffolding-Protein-Derived Peptide in Patients with IPF” under the Company’s Protocol LTI-03-2001.
+Added: Pursuant to the project addendum, the Company had contracted for up to $ 19.8 million of master services.
+Added: Advisory Agreements
+Added: The Company has entered into various arrangements with certain business advisors, consultants, and investment institutions to assist the Company with fundraising and to provide certain advisory services.
+Added: In connection with these arrangements, the Company may be required to pay such business advisors, consultants, and investment institutions certain contingent fees related to their services to the extent that certain conditions are met, such as the successful fundraising.
+Added: There are no contingent fees payable under these arrangements as of December 31, 2025 or December 31, 2024.
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.
−Removed: 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.
+Added: 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.
−Removed: 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 December 31, 2024 or 2023.
+Added: 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 December 31, 2025 or December 31, 2024.
Segment Reporting
5 unchanged sentences
The CODM uses net loss predominantly in the annual operating budget and in the strategic planning and forecasting process.
−Removed: Such loss measure is used to monitor budget versus actual results on an ongoing basis by the
−Removed: CODM and determine how resources are allocated to the various activities of the Company.
+Added: Such loss measure is used to monitor budget versus actual results on an ongoing basis by the CODM and determine how resources are allocated to the various activities of the Company.
The CODM also uses net loss to evaluate the Company’s performance and assist in determination of management’s incentive compensation.
25 unchanged sentences
Impairment loss on intangible assets
−Removed: Restructuring and other costs
Other income, net
2 unchanged sentences
On October 31, 2023, the Company acquired, in accordance with the terms of the Lung Acquisition Agreement, the stock of Lung.
−Removed: In accordance with ASC 805-740-25-3, recognition of deferred tax assets and liabilities is required for substantially all temporary differences and acquired tax carryforwards and credits.
+Added: In accordance with ASC 805, Business Combination , recognition of deferred tax assets and liabilities is required for substantially all temporary differences and acquired tax carryforwards and credits.
The Company has computed estimated temporary differences and acquired tax carryforwards and credits as of the transaction date.
1 unchanged sentence
For accounting purposes, the intangible assets will not be amortized and subject to impairment review and testing.
−Removed: Though the tax effects may be delayed indefinitely, ASC 740-10-55-63 states that “deferred tax liabilities may not be eliminated or reduced because a reporting entity may be able to delay the settlement of those liabilities by delaying the events that would cause taxable temporary differences to reverse.” As such, the Company has recorded a deferred tax liability for the portion of the liability that cannot be offset with indefinite lived deferred tax assets.
+Added: Though the tax effects may be delayed indefinitely, ASC 740, Accounting for Income Taxes, states that “deferred tax liabilities may not be eliminated or reduced because a reporting entity may be able to delay the settlement of those liabilities by delaying the events that would cause taxable temporary differences to reverse.” As such, the Company has recorded a deferred tax liability for the portion of the liability that cannot be offset with indefinite lived deferred tax assets.
The Company reported an income tax benefit of $ 712 for the year ended December 31, 2025.
The reported amount of income tax expense for the years differs from the amount that would result from applying domestic federal statutory tax rates to pretax losses primarily because of changes in valuation allowance and indefinite lived intangibles.
−Removed: Income tax (benefit) expense consist of the following:
+Added: Income tax benefit consist of the following :
Year Ended December 31,
2 unchanged sentences
Deferred tax (provision) benefit:
−Removed: Total deferred tax provision (benefit)
−Removed: Total income tax provision (benefit)
+Added: Total deferred tax benefit
+Added: Total income tax benefit
A reconciliation of the U.S.
1 unchanged sentence
Year Ended December 31, 2025
+Added: Year Ended December 31, 2024
Federal statutory income tax rate
−Removed: State taxes, net of federal benefit
+Added: State and local income taxes, net of federal benefit
Research and development and orphan drug tax credits
+Added: Nontaxable or nondeductible items
+Added: Foreign Tax Effects
+Added: Effects of Cross-Border Tax Laws
+Added: Changes in Unrecognized Tax Benefits
+Added: Effect of Changes in Tax Laws or Rates Enacted in the Current Period
+Added: Change in valuation allowances
Stock compensation
−Removed: Other permanent items
−Removed: Change in deferred tax asset valuation allowance
−Removed: Loss of federal net operating losses due to 382
+Added: Other reconciling items
Effective income tax rate
5 unchanged sentences
Accrued expenses and reserves
−Removed: Depreciation and amortization
−Removed: Lease liability
Stock compensation
7 unchanged sentences
Net deferred tax liability
+Added: The Company owns Lung Therapeutics, LLC, Lung Therapeutics Australia Pty Ltd, and Lung Therapeutics Limited.
+Added: There is no material foreign activity during the year ended December 31, 2025.
+Added: There are no foreign tax attributes for the Company as of December 31, 2024 or December 31, 2025, respectively.
+Added: As such, certain items have not been separately disaggregated in the income tax disclosures, as it was determined that such disaggregation would not be material, consistent with the materiality guidance in ASC 105-10-05-6.
As of December 31, 2025, the Company had net operating loss carryforwards for federal and state purposes of $ 122,682 and $ 46,077 , respectively.
8 unchanged sentences
Of this amount, $ 2,222 of research and development credit carryforwards and $ 5,644 of orphan drug credit carryforwards came over from the Lung Acquisition.
−Removed: On December 22, 2017, the Tax Cuts and Jobs Act, or the TCJA, was signed into law.
−Removed: Under the TCJA provisions, effective with tax years beginning on or after January 1, 2022, taxpayers can no longer immediately expense research and development expenditures.
−Removed: Taxpayers are now required to capitalize and amortize these costs over 5 years for research conducted within the United States or 15 years for research conducted abroad.
−Removed: As a result, the Company capitalized $ 14,220 of research and development expenses for the year ended December 31, 2024 for tax purposes.
+Added: On July 4, 2025, the One Big Beautiful Bill Act (“OBBBA”) was enacted.
+Added: The OBBBA amends U.S.
+Added: tax law including provisions related to domestic research and development expenses and bonus depreciation, among others.
+Added: Under the OBBBA provisions, effective with tax years beginning on or after January 1, 2025, taxpayers can now immediately expense domestic research and development expenditures as well as accelerate previously capitalized domestic research and development expenditures from 2022-2024.
+Added: Taxpayers are still required to capitalize and amortize research and development expenditures over 15 years for research conducted abroad.
+Added: As a result, the Company expensed net $ 25,277 of research and development expenses for the year ended December 31, 2025 for tax purposes.
Utilization of the net operating loss carryforwards and research and development tax credit carryforwards may be subject to a substantial annual limitation under Section 382 of the Internal Revenue Code of 1986 due to ownership changes that have occurred previously or that could occur in the future.
3 unchanged sentences
The Company expects to have all prior year net operating losses and tax credits of its legacy business to be completely limited going forward due to the lack of continuation in its legacy business.
−Removed: As such, all prior year net operating losses and tax credits have been written down to zero as of December 31, 2023 and December 31, 2024, respectively.
−Removed: The remaining net operating losses and tax credits as of December 31, 2024 relate to post-merger activity in the year, as well as acquired attributes as part of the merger in the year.
+Added: As such, all prior year net operating losses and tax credits have been written down to zero as of December 31, 2023 through December 31, 2025, respectively.
+Added: The remaining net operating losses and tax credits as of December 31, 2025 relate to post-merger
+Added: activity, as well as acquired attributes as part of the merger.
A study has been completed on the Target ownership shifts through December 31, 2023, and multiple ownership changes were determined.
5 unchanged sentences
Management reevaluates the positive and negative evidence at each reporting period.
−Removed: The decrease in the valuation allowance as of December 31, 2023 of $ 58,935 related primarily to the deferred tax liability recognized as a result of the transaction as well as the reduction in prior year deferred tax assets due to Section 382 limitations.
−Removed: The increase in the valuation allowance for deferred tax assets during the year ended December 31, 2024 of $ 11,948 related primarily to an increase in net operating loss carryforwards.
+Added: The increase in the valuation allowance for deferred tax assets during the years ended December 31, 2025 and December 31, 2024 of $ 11,675 and $ 11,948 , respectively, related primarily to an increase in net operating loss carryforwards.
Changes in the valuation allowance were as follows:
1 unchanged sentence
Valuation allowance at beginning of year
−Removed: Increases recorded to income tax provision
Decreases recorded as a benefit to income tax provision
2 unchanged sentences
The Company files tax returns as prescribed by the tax laws of the jurisdictions in which it operates.
+Added: The major jurisdictions of the Company are federal and Massachusetts.
In the normal course of business, the Company is subject to examination by federal and state jurisdictions, where applicable.
4 unchanged sentences
As of December 31, 2025 and 2024, the Company had no accrued interest or penalties related to uncertain tax positions and no amounts have been recognized in the Company’s consolidated statements of operations and comprehensive loss.
−Removed: Related Party Transactions
−Removed: On May 8, 2024, a greater than 5 % shareholder converted 421 shares of the Company’s Series X Preferred Stock into 421,000 shares of common stock.
−Removed: Subsequent Event
+Added: There are no foreign jurisdictions that the Company operates in as of December 31, 2024 or December 31, 2025, respectively.
+Added: Subsequent Events
The Company evaluated subsequent events and transactions that occurred after the balance sheet date up to the date that the financial statements were issued.
Based upon this review, other than as described below, the Company did not identify any subsequent events that would have required adjustment or disclosure in the financial statements.
−Removed: Subsequent to the consolidated balance sheet date, the Company continued its “at the market” offering program under the Equity Distribution Agreement (described in Note 1).
−Removed: In January 2025, the Company issued and sold 317,772 shares of common stock pursuant to the “at the market” offering program for total net proceeds of $ 712 , after deducting transaction fees of $ 22 paid by the Company.
−Removed: On March 29, 2025, the Company entered into a payment plan agreement to settle an outstanding obligation related to LTI-01 manufacturing.
−Removed: Under the terms of the agreement, the Company has agreed to pay a total of $ 1,676 in equal installments over the course of twelve months, with the final payment due on February 14, 2026.
−Removed: This agreement does not bear interest.
−Removed: This agreement was executed after the balance sheet date but prior to the issuance of this Annual Report on Form 10-K.
−Removed: Management has evaluated the financial impact of this agreement and determined that it does not materially affect the Company’s financial position as of December 31, 2024 as the Company has recorded the proper liability balance in proper accounts for such outstanding obligation as of December 31, 2024.
+Added: At the Market Offering
+Added: Subsequent to the consolidated balance sheet date, the Company continued its “at the market” offering program under the Wainwright Sales Agreement (described in Notes 1 and 8).
+Added: Through March 26, 2026, the Company issued and sold 296,810 shares of common stock pursuant to the “at the market” offering program for total net proceeds of $ 354 , after deducting transaction fees of $ 16 paid by the Company.
+Added: 2026 Bridge Loans
+Added: In January 2026 and February 2026, the Company entered into separate securities purchase agreements, or the Purchase Agreements, with three institutional investors pursuant to which we issued and sold to the investors, in a private placement, unsecured promissory notes in the aggregate original principal amount of $ 5,375 , or the Notes.
+Added: Pursuant to the Purchase Agreements, the Company issued and sold the Notes to the investors for the aggregate purchase price of $ 4,300 , inclusive of an original issue discount of 20 %.
+Added: The Notes have a stated maturity date of the earlier of (i) the date of the closing of the next issuance and sale of the Company’s securities, in a single transaction or series of related transactions, to investors resulting in gross proceeds to the Company of at least $ 10,000 (exclusive of the Notes proceeds) or (ii) June 30, 2026.
+Added: The Company’s obligations under the Notes are unsecured.
+Added: There is no interest payable under the promissory notes other than the 20 %
+Added: original issue discount.
+Added: The Purchase Agreements contained representations, warranties, covenants and other terms customary for agreements of such nature.
+Added: Issuance of Common Stock
+Added: In January 2026 and March 2026, the Company issued 192,000 shares of common stock for the restricted stock units granted and vested in August 2025.
Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.