Summary Of Significant Accounting Policies	3 Months Ended
Mar. 31, 2026
Accounting Policies [Abstract]
Summary Of Significant Accounting Policies	2. Summary Of Significant Accounting Policies There have been no significant changes from the significant accounting policies and estimates disclosed in Note 2 of the “Notes to Consolidated Financial Statements” in the audited consolidated financial statements for the year ended December 31, 2025 and notes thereto, included in the Company’s registration statement on Form S-1. Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP, and applicable rules and regulations of the U.S. Securities and Exchange Commission, or the SEC, regarding interim financial reporting. Accordingly, they do not include all disclosures normally required in annual consolidated financial statements prepared in accordance with U.S. GAAP. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification, or ASC, and ASUs of the Financial Accounting Standards Board, or FASB. Principles of Consolidation The consolidated financial statements include the accounts of Avalyn Pharma Inc. and its wholly owned subsidiary, Avalyn Pharma Pty. Ltd. All intercompany accounts and transactions have been eliminated in consolidation. The consolidated financial statements have been prepared in conformity with U.S. GAAP. Use of Estimates The preparation of consolidated financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expense during the reporting period. The Company bases its estimates on historical experience and various other assumptions that management believes to be reasonable under the circumstances. Management evaluates its estimates and assumptions on an ongoing basis. Changes in estimates are recorded in the period in which they become known. Significant estimates and assumptions relied upon in preparing these financial statements include, but are not limited to, research and development expenses and related prepaid or accrued costs, and the valuation of common stock and related stock-based compensation expense. The Company’s actual results may differ from these estimates under different assumptions or conditions. Deferred Offering Costs The Company capitalizes certain legal, professional accounting, and other third-party fees that are incremental costs and directly associated with in-process equity and debt financings as deferred offering costs within non-current assets on the consolidated balance sheets until such time the equity and debt financings are consummated. After consummation of an equity financing, these costs are recorded as a reduction of the proceeds from the offering, either as a reduction to the carrying value of the preferred stock or, for the issuances of common stock, in stockholders’ deficit as a reduction of additional paid-in capital generated as a result of the offering. Should the in-process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the consolidated statements of comprehensive loss. As of March 31, 2026 and December 31, 2025, there were deferred offering costs of $2.7 million and $0.3 million, respectively. Recently Issued Accounting Pronouncements Not Yet Adopted In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, or ASU 2024-03, which requires disclosures about specific types of expenses included in the expense captions presented on the face of the income statement as well as disclosures about selling expenses. The requirements of ASU 2024-03 are effective for annual periods beginning after December 15, 2026, and for interim periods beginning after December 15, 2027, with early adoption permitted. The requirements will be applied prospectively with the option for retrospective application. The Company is currently in the process of evaluating the effects of this pronouncement on its related disclosures.

There have been no significant changes from the significant accounting policies and estimates disclosed in Note 2 of the “Notes to Consolidated Financial Statements” in the audited consolidated financial statements for the year ended December 31, 2025 and notes thereto, included in the Company’s registration statement on Form S-1.

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or U.S. GAAP, and applicable rules and regulations of the U.S. Securities and Exchange Commission, or the SEC, regarding interim financial reporting. Accordingly, they do not include all disclosures normally required in annual consolidated financial statements prepared in accordance with U.S. GAAP. Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification, or ASC, and ASUs of the Financial Accounting Standards Board, or FASB.

Principles of Consolidation

The consolidated financial statements include the accounts of Avalyn Pharma Inc. and its wholly owned subsidiary, Avalyn Pharma Pty. Ltd. All intercompany accounts and transactions have been eliminated in consolidation. The consolidated financial statements have been prepared in conformity with U.S. GAAP.

Use of Estimates

The preparation of consolidated financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of income and expense during the reporting period. The Company bases its estimates on historical experience and various other assumptions that management believes to be reasonable under the circumstances. Management evaluates its estimates and assumptions on an ongoing basis. Changes in estimates are recorded in the period in which they become known. Significant estimates and assumptions relied upon in preparing these financial statements include, but are not limited to, research and development expenses and related prepaid or accrued costs, and the valuation of common stock and related stock-based compensation expense. The Company’s actual results may differ from these estimates under different assumptions or conditions.

Deferred Offering Costs

The Company capitalizes certain legal, professional accounting, and other third-party fees that are incremental costs and directly associated with in-process equity and debt financings as deferred offering costs within non-current assets on the consolidated balance sheets until such time the equity and debt financings are consummated. After consummation of an equity financing, these costs are recorded as a reduction of the proceeds from the offering, either as a reduction to the carrying value of the preferred stock or, for the issuances of common stock, in stockholders’ deficit as a reduction of additional paid-in capital generated as a result of the offering. Should the in-process equity financing be abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the consolidated statements of comprehensive loss. As of March 31, 2026 and December 31, 2025, there were deferred offering costs of $2.7 million and $0.3 million, respectively.

Recently Issued Accounting Pronouncements Not Yet Adopted

In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, or ASU 2024-03, which requires disclosures about specific types of expenses included in the expense captions presented on the face of the income statement as well as

disclosures about selling expenses. The requirements of ASU 2024-03 are effective for annual periods beginning after December 15, 2026, and for interim periods beginning after December 15, 2027, with early adoption permitted. The requirements will be applied prospectively with the option for retrospective application. The Company is currently in the process of evaluating the effects of this pronouncement on its related disclosures.