X0508 4 2025-06-17 0 0001974640 Apogee Therapeutics, Inc. APGE 0001802528 Fairmount Funds Management LLC 200 BARR HARBOR DRIVE SUITE 400 WEST CONSHOHOCKEN PA 19428 1 0 0 0 0001830177 Kiselak Tomas 2001 MARKET STREET SUITE 2500 PHILADELPHIA PA 19103 1 0 0 0 0001663607 Harwin Peter Evan 2001 MARKET STREET SUITE 2500 PHILADELPHIA PA 19103 1 0 0 0 0 Stock Option (Right to Buy) 41.66 2025-06-17 4 A 0 14461 0.00 A 2035-06-17 Common Stock 14461 14461 I By: Peter Harwin Stock Option (Right to Buy) 41.66 2025-06-17 4 A 0 14461 0.00 A 2035-06-17 Common Stock 14461 14461 I By: Tomas Kiselak This option represents the right to purchase 14,461 shares of the Issuer's common stock and will vest on the one-year anniversary of the grant date, subject to the Reporting Person's continued service to the Issuer on such vesting date. Under Mr. Harwin's arrangement with Fairmount Funds Management LLC ('Fairmount'), Mr. Harwin holds the option for one or more investment vehicles managed by Fairmount (each, a "Fairmount Fund"). Mr. Harwin is obligated to turn over to Fairmount any net cash or stock received from the option for the benefit of such Fairmount Fund. Mr. Harwin therefore disclaims beneficial ownership of the option and underlying common stock. Fairmount disclaims beneficial ownership of any of the reported securities, except to the extent of its pecuniary interest therein. Under Mr. Kiselak's arrangement with Fairmount, Mr. Kiselak holds the option for one or more Fairmount Funds. Mr. Kiselak is obligated to turn over to Fairmount any net cash or stock received from the option for the benefit of such Fairmount Fund. Mr. Kiselak therefore disclaims beneficial ownership of the option and underlying common stock. Fairmount disclaims beneficial ownership of any of the reported securities, except to the extent of its pecuniary interest therein. Fairmount may be deemed a director by deputization of Issuer by virtue of the fact that each of Peter Harwin and Tomas Kiselak serve on the board of directors of Issuer and are also each a Managing Member of Fairmount. /s/ Tomas Kiselak, Managing Member of Fairmount Funds Management LLC 2025-06-20 /s/ Tomas Kiselak 2025-06-20 /s/ Peter Harwin 2025-06-20