FORM 10-Q (Mark One) For the quarterly period ended March 31, 2026 or ☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ___________ to__________ Commission file number: 001-36199 PULMATRIX, INC.(Exact name of registrant as specified in its charter) Delaware46-1821392(State or other jurisdiction ofincorporation or organization)(I.R.S. EmployerIdentification No.) 945 Concord Street, Suite 1217Framingham, MA01701(Address of principal executive offices)(Zip Code) (888) 355-4440Registrant’s telephone number, including area code N/A(Former name, former address and former fiscal year, if changed since last report) Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the SecuritiesExchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports),and (2) has been subject to such filing requirements for the past 90 days. Yes☒No☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submittedpursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required tosubmit such files). Yes☒No☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smallerreporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer”, “smallerreporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one): Large accelerated filer☐ Non-accelerated filer☒ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period forcomplying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes☐No☒ As of May 11, 2026, the registrant had 3,652,285 shares of common stock outstanding. PULMATRIX, INC.FORM 10-QFOR THE QUARTERLY PERIOD ENDED MARCH 31, 2026TABLE OF CONTENTS Page No. PART I—FINANCIAL INFORMATION Item 1.Condensed Consolidated Financial Statements (unaudited)1Consolidated Balance Sheets as of March 31, 2026 and December 31, 20251Consolidated Statements of Operations for the Three Months Ended March 31, 2026 and 20252Consolidated Statements of Stockholders’ Equity for the Three Months Ended March 31, 2026 and 20253Consolidated Statements of Cash Flows for the Three Months Ended March 31, 2026 and 20254Notes to Condensed Consolidated Financial Statements5Item 2.Management’s Discussion and Analysis of Financial Condition and Results of Operations12Item 3.Quantitative and Qualitative Disclosures About Market Risk23Item 4.Controls and Procedures23 PART II—OTHER INFORMATION Item 1.Legal Proceedings24Item 1A.Risk Factors24Item 2.Unregistered Sales of Equity Securities and Use of Proceeds25Item 3.Defaults Upon Senior Securities25Item 4.Mine Safety Disclosures25Item 5.Other Information25Item 6.Exhibits25 SIGNATURES26 PART I—FINANCIAL INFORMATION PULMATRIX, INC.Consolidated Balance Sheets(in thousands, except share and per share data) PULMATRIX, INC.Consolidated Statements of Operations(in thousands, except share and per share data)(unaudited) PULMATRIX, INC.Consolidated Statements of Cash Flows(in thousands)(unaudited) PULMATRIX, INC.Notes to Condensed Consolidated Financial Statements (Unaudited)(in thousands, except share and per share data) 1. Organization Pulmatrix, Inc. (“Pulmatrix” or the “Company”) was incorporated in 2013 as a Delaware corporation. The Company is abiopharmaceutical company that has focused on the development of a novel inhaled therapeutic products intended to prevent and treatmigraine and respiratory diseases with important unmet medical needs using its patented iSPERSE™ technology. The Company’sproprietary dry powder delivery platform, iSPERSE™, is engineered to deliver small, dense particles with highly efficientdispersibility and delivery to the airways, which can be used with an array of dry powder inhaler technologies and can be formulatedwith a variety of drug substances. Agreement and Plan of Merger and Reorganization On March 26, 2026, Pulmatrix and Eos SENOLYTIX, Inc., a Delaware corporation (“Eos”), entered into an Agreement and Plan ofMerger and Reorganization (the “Merger Agreement”), pursuant to which, among other matters, PUOS Merger Sub, Inc., a directwholly owned subsidiary of Pulmatrix (“Merger Sub”), will merge with and into Eos, with Eos continuing as the surviving corporationand a wholly owned subsidiary of Pulmatrix (the “Merger”). In connection with the Merger, Eos and Pulmatrix entered into definitiveagreements for concurrent private financings of $19 million i