X0202 SCHEDULE 13G 0002149521 XXXXXXXX LIVE Voting Common Stock, $0.001 par value per share 06/30/2026 0001540171 Avalyn Pharma Inc. 05348Y105 105 W First Street Boston MA 02127 Rule 13d-1(d) Norwest Venture Partners XV, LP b DE 0.00 2268404.00 0.00 2268404.00 2268404.00 5.1 PN Genesis VC Partners XV, LLC b DE 0.00 2268404.00 0.00 2268404.00 2268404.00 5.1 OO NVP Associates, LLC b DE 0.00 2268404.00 0.00 2268404.00 2268404.00 5.1 OO Jeffrey Crowe b X1 0.00 2268404.00 0.00 2268404.00 2268404.00 5.1 IN Jon Erik Kossow b X1 0.00 2268404.00 0.00 2268404.00 2268404.00 5.1 IN Avalyn Pharma Inc. 105 W First Street, Boston, MA, 02127. The names of the persons filing this report (collectively, the "Reporting Persons") are: Norwest Venture Partners XV, LP ("NVP XV") Genesis VC Partners XV, LLC ("Genesis XV") NVP Associates, LLC ("NVP Associates") Jeffrey Crowe ("Crowe") Jon E. Kossow ("Kossow") The Reporting Persons expressly disclaim status as a "group" for purposes of this Schedule 13G. 1300 El Camino Real, Suite 200 Menlo Park, CA 94024 NVP XV Delaware Genesis XV Delaware NVP Associates Delaware Crowe United States Kossow United States Y Row 9 of each Reporting Person's cover page to this Schedule 13G sets forth the aggregate number of shares of voting common stock of the Issuer beneficially owned by such Reporting Person as of June 30, 2026 and is incorporated by reference. The Reporting Persons' beneficial ownership of the Issuer's securities consists of 2,268,404 shares of voting common stock directly held by NVP XV. Genesis XV is the general partner of NVP XV, NVP Associates is the managing member of Genesis XV and Crowe and Kossow are Co-Chief Executive Officers of NVP Associates. Each of Genesis XV, NVP Associates, Crowe and Kossow, may be deemed to share voting and investment authority over these shares. Row 11 of each Reporting Person's cover page to this Schedule 13G sets forth the percentages of the securities of the Issuer beneficially owned by such Reporting Person as of June 30, 2026 and is incorporated by reference. The percentage set forth in each row 11 is based upon 44,333,095 shares of voting common stock outstanding as of June 2, 2026, as reported in the Issuer's Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission (the "SEC") on June 3, 2026. Row 5 of each Reporting Person's cover page to this Schedule 13G sets forth the sole power to vote or to direct the vote of securities of the Issuer beneficially owned by such Reporting Person as of June 30, 2026 and is incorporated by reference. Row 6 of each Reporting Person's cover page to this Schedule 13G sets forth the shared power to vote or to direct the vote of securities of the Issuer beneficially owned by such Reporting Person as of June 30, 2026 and is incorporated by reference. Row 7 of each Reporting Person's cover page to this Schedule 13G sets forth the sole power to dispose or to direct the disposition of securities of the Issuer beneficially owned by such Reporting Person as of June 30, 2026 and is incorporated by reference. Row 8 of each Reporting Person's cover page to this Schedule 13G sets forth the shared power to dispose or to direct the disposition of securities of the Issuer beneficially owned by such Reporting Person as of June 30, 2026 and is incorporated by reference. Y Y Y Y Y Y Exhibit 99.1 Joint Filing Agreement Norwest Venture Partners XV, LP /s/ Matthew De Dominicis 08/11/2026 Genesis VC Partners XV, LLC /s/ Matthew De Dominicis 08/11/2026 NVP Associates, LLC /s/ Matthew De Dominicis 08/11/2026 Jeffrey Crowe /s/ Matthew De Dominicis 08/11/2026 Jon Erik Kossow /s/ Matthew De Dominicis 08/11/2026