X0609 4 2026-09-15 0001768446 Climb Bio, Inc. CLYM 0002027962 Thomas Stephen Basil false C/O CLIMB BIO, INC. 20 WILLIAM STREET, SUITE G50 WELLESLEY HILLS MA 02481 true false false false true Common Stock 2026-09-15 4 S false 100000 13.6682 D 467969 D These transactions were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on June 16, 2026. The price reported is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.3800 to $14.3400, inclusive. The reporting person undertakes to provide the staff of the Securities and Exchange Commission, the issuer or any security holder of the issuer, upon request, full information regarding the number of shares sold at each separate price within the range. Includes 413,312 shares of the issuer's common stock, par value $0.0001 per share, distributed by Sera Medicines, LLC to certain of its limited partners, including the reporting person, for no consideration in a pro-rata in-kind distribution. /s/ Chandra Adams, as Attorney-in-Fact 2026-09-17