X0306 4 2021-03-12 0 0001808158 Repare Therapeutics Inc. RPTX 0001134655 GADICKE ANSBERT C/O MPM CAPITAL 450 KENDALL STREET CAMBRIDGE MA 02142 0 0 1 0 Common Shares 2021-03-12 4 S 0 695000 28.18 D 4697109 I See Footnote Common Shares 2021-03-15 4 J 0 24271 A 4672838 I See Footnote The shares were sold as follows: 363,887 by MPM BioVentures 2014, L.P. ("BV 2014"), 12,525 by MPM Asset Management Investors BV2014 LLC ("AM BV2014") and 318,588 by UBS Oncology Impact Fund L.P. ("UBS Oncology"). MPM BioVentures 2014 GP LLC and MPM BioVentures 2014 LLC ("BV LLC") are the direct and indirect general partners of BV 2014 and BV 2014(B). BV LLC is the manager of AM BV2014. Ansbert Gadicke is a managing director of BV LLC. MPM Oncology Impact Management GP LLC ("Oncology GP LLC") is the General Partner of MPM Oncology Impact Management LP, the General Partner of Oncology Impact Fund (Cayman) Management L.P., the General Partner of UBS Oncology Impact Fund, L.P. Ansbert Gadicke is the managing director of Oncology GP LLC. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. The shares are held as follows: 2,364,040 by BV 2014, 181,948 by MPM BioVentures 2014(B), L.P. ("BV 2014(B)"), 81,372 by AM BV2014 and 2,069,749 by UBS Oncology. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. Represents a pro rata in-kind distribution from BV 2014(B) to its limited partners for no consideration. The shares are held as follows: 2,364,040 by BV 2014, 157,677 by BV 2014(B), 81,372 by AM BV2014 and 2,069,749 by UBS Oncology. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein. /s/ Ansbert Gadicke 2021-03-15