X0202 SCHEDULE 13G/A 0001690310 XXXXXXXX LIVE 2 Ordinary Shares, nominal value 0.002 per share 06/30/2026 0001847903 Centessa Pharmaceuticals plc 152309100 3RD FLOOR, 1 ASHLEY ROAD ALTRINCHAM CHESHIRE X0 WA14 2DT Rule 13d-1(d) Medicxi Growth I LP b Y9 0 0 0 0 0 N 0.0 PN Medicxi Growth Co-Invest I LP b Y9 0 0 0 0 0 N 0.0 PN Medicxi Growth I GP Limited b Y9 0 0 0 0 0 N 0.0 OO Medicxi Ventures I LP b Y9 0 0 0 0 0 N 0.0 PN Medicxi Co-Invest I LP b Y9 0 0 0 0 0 N 0.0 PN Medicxi Ventures I GP Limited b Y9 0 0 0 0 0 N 0.0 OO Medicxi Secondary I LP b Y9 0 0 0 0 0 N 0.0 PN Medicxi Secondary Co-Invest I LP b Y9 0 0 0 0 0 N 0.0 PN Medicxi Secondary I GP Limited b Y9 0 0 0 0 0 N 0.0 OO Medicxi Ventures Management (Jersey) Limited b Y9 0 0 0 0 0 N 0.0 OO Centessa Pharmaceuticals plc 3rd Floor, 1 Ashley Road, Altrincham Cheshire WA14 2DT United Kingdom (i) Medicxi Growth I LP ("Growth I"), a Jersey limited partnership; (ii) Medicxi Growth Co-Invest I LP ("Growth Co-Invest I"), a Jersey limited partnership; (iii) Medicxi Growth I GP Limited ("Growth I GP"), a Jersey limited liability company, which is the sole managing general partner of Growth I and Growth Co-Invest I; (iv) Medicxi Ventures I LP ("Ventures I"), a Jersey limited partnership; (v) Medicxi Co-Invest I LP ("Co-Invest I"), a Jersey limited partnership; (vi) Medicxi Ventures I GP Limited ("Ventures I GP"), a Jersey limited liability company, which is the sole managing general partner of Ventures I and Co-Invest I; (vii) Medicxi Secondary I LP ("Secondary I"), a Jersey limited partnership; (viii) Medicxi Secondary Co-Invest I LP ("Secondary Co-Invest I" and, together with Growth I, Growth Co-Invest I, Ventures I, Co-Invest I and Secondary I, the "Medicxi Funds"), a Jersey limited partnership; (ix) Medicxi Secondary I GP Limited ("Secondary I GP"), a Jersey limited liability company, which is the sole managing general partner of Secondary I and Secondary Co-Invest I; and (x) Medicxi Ventures Management (Jersey) Limited ("Medicxi Manager"), a Jersey limited liability company, which is the sole manager of the Medicxi Funds. Growth I, Growth Co-Invest I, Growth I GP, Ventures I, Co-Invest I, Ventures I GP, Secondary I, Secondary Co-Invest I, Secondary I GP and Medicxi Manager are sometimes individually referred to herein as a "Reporting Person" and collectively as the "Reporting Persons." The address of the principal business office of each of the Reporting Persons is c/o CSC Fund Services (Jersey) Limited, 44 Esplanade, St. Helier, Jersey JE4 9WG. See Item 2(a). Y As of June 30, 2026, none of the Reporting Persons may be deemed to beneficially own any Ordinary Shares of the Issuer. 0.0 0 0 0 0 Y Y Y Y Y Y Medicxi Growth I LP /s/ Francois Chesnay 08/04/2026 Medicxi Growth Co-Invest I LP /s/ Francois Chesnay 08/04/2026 Medicxi Growth I GP Limited /s/ Francois Chesnay 08/04/2026 Medicxi Ventures I LP /s/ Francois Chesnay 08/04/2026 Medicxi Co-Invest I LP /s/ Francois Chesnay 08/04/2026 Medicxi Ventures I GP Limited /s/ Francois Chesnay 08/04/2026 Medicxi Secondary I LP /s/ Francois Chesnay 08/04/2026 Medicxi Secondary Co-Invest I LP /s/ Francois Chesnay 08/04/2026 Medicxi Secondary I GP Limited /s/ Francois Chesnay 08/04/2026 Medicxi Ventures Management (Jersey) Limited /s/ Francois Chesnay 08/04/2026