X0609 4 2026-08-07 0 0001974640 Apogee Therapeutics, Inc. APGE 0001802528 Fairmount Funds Management LLC false 200 BARR HARBOR DRIVE SUITE 400 WEST CONSHOHOCKEN PA 19428 1 0 0 0 0001769651 Fairmount Healthcare Fund II L.P. false 200 BARR HARBOR DRIVE SUITE 400 WEST CONSHOHOCKEN PA 19428 1 0 0 0 0001830177 Kiselak Tomas false 200 BARR HARBOR DRIVE SUITE 400 WEST CONSHOHOCKEN PA 19428 1 0 0 0 0001663607 Harwin Peter Evan false 200 BARR HARBOR DRIVE SUITE 400 WEST CONSHOHOCKEN PA 19428 1 0 0 0 0 Common Stock 2026-08-07 4 M 0 31838 17.00 A 330485 I By Fairmount Healthcare Fund II LP Common Stock 2026-08-07 4 M 0 10370 43.85 A 340855 I By Fairmount Healthcare Fund II LP Common Stock 51166 I By Tomas Kiselak Common Stock 51166 I By Peter Harwin Stock Option (Right to Buy) 17 2026-08-07 4 M 0 31838 0 D 2033-07-13 Common Stock 31838 0 D Stock Option (Right to Buy) 43.85 2026-08-07 4 M 0 10370 0 D 2034-06-05 Common Stock 10370 0 D Fairmount Funds Management LLC ("Fairmount") is the investment manager for Fairmount Healthcare Fund II L.P. The managers of Fairmount are Peter Harwin and Tomas Kiselak. Fairmount, Mr. Harwin, and Mr. Kiselak disclaim beneficial ownership of any of the reported securities, except to the extent of their pecuniary interest therein. This option represented the vested portion of the total right to purchase 47,758 shares of the Issuer's common stock, which vested in three approximately equal annual installments beginning on the first anniversary of the 7/13/2023 grant date. Under Mr. Harwin's arrangement with Fairmount Funds Management LLC (the "Adviser"), Mr. Harwin held the options reported herein for one or more investment vehicles managed by the Adviser (each, a "Fairmount Fund"). Mr. Harwin was obligated to turn over to the Adviser any net cash or stock received from the options for the benefit of such Fairmount Fund. Mr. Harwin therefore disclaimed beneficial ownership of the option and underlying common stock. This option represented the right to purchase 10,370 shares of the Issuer's common stock, which vested on the one-year anniversary of the 6/5/2024 grant date. Fairmount and Fairmount Healthcare Fund II LP may each be deemed a director by deputization of the Issuer by virtue of the fact that Tomas Kiselak serves on the board of directors of the Issuer and is a Managing Member of Fairmount. /s/ Tomas Kiselak, Managing Member of Fairmount Funds Management LLC 2026-08-11 /s/ Tomas Kiselak, Managing Member of Fairmount Healthcare Fund II LP 2026-08-11 /s/ Tomas Kiselak 2026-08-11 /s/ Peter Harwin 2026-08-11