X0508 4/A 2026-03-13 2026-03-13 0 0001847903 Centessa Pharmaceuticals plc CNTA 0001762176 Anderson Karen M. C/O CENTESSA PHARMACEUTICALS PLC 3RD FL., 1 ASHLEY RD, ALTRINCHAM CHESHIRE X0 WA14 2DT UNITED KINGDOM 0 1 0 0 Chief People Officer 1 Ordinary Shares 2026-03-13 4 M 0 94224 4.01 A 166940 D Ordinary Shares 2026-03-13 4 M 0 15174 3.85 A 182114 D Ordinary Shares 2026-03-13 4 S 0 107961 26.1505 D 74153 D Ordinary Shares 2026-03-13 4 S 0 12068 27.1328 D 62085 D Share Option (right to buy) 4.01 2026-03-13 4 M 0 94224 0 D 2032-12-01 Ordinary Shares 94224 149811 D Share Option (right to buy) 3.85 2026-03-13 4 M 0 15174 0 D 2033-02-01 Ordinary Shares 15174 28336 D The Ordinary Shares may be represented by American Depositary Shares, each of which currently represents one Ordinary Share. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 12, 2025. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $25.75 to $26.705, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $26.805 to $27.455, inclusive. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range. 25% of the shares subject to such option shall vest and become exercisable on December 1, 2023 and the remaining 75% of the shares subject to such option shall vest and become exercisable in 36 monthly installments on the first day of each month thereafter. 1/48th of the shares subject to such option shall vest and become exercisable in equal monthly installments with the first installment vesting on March 1, 2023. This Form 4/A amends and restates the Form 4 filed on March 13, 2026 to correct the reporting of stock option exercises. The exercises were previously reported as originating from a single option grant but were exercised from two separate option grants with different exercise prices. This amendment reports the exercises from each grant at the applicable exercise prices. Except for the corrected reporting of the option exercises, the transactions and amounts previously reported remain unchanged. /s/ Raphael Deferiere, attorney-in-fact 2026-03-16