Repare Therapeutics Inc. reported initial proof of concept monotherapy data from its Phase 1 MYTHIC clinical trial evaluating lunresertib (RP-6306), a first-in-class, oral PKMYT1 inhibitor in molecularly selected advanced solid tumors. These initial proof of concept results for lunresertib monotherapy show a favorable and distinct tolerability profile and preliminary antitumor activity that support development plans for this program. These genetic alterations have previously been considered undruggable and represent a significant unmet medical need.

These findings, along with the continued advancement of the lunresertib program across multiple ongoing combination clinical trials, validate proprietary STEP platform and precision medicine approach. While early, these promising proof-of-concept data continue to support belief in the potential transformative role that lunresertib could play, either alone or in combination with other therapies, in patients with molecularly selected advanced solid tumors, said Lloyd M. Segal, President and Chief Executive Officer of Repare. MYTHIC (NCT04855656) Module 1 is a first-in-human, global, open-label Phase 1 dose-escalation study to evaluate safety, pharmacokinetics, pharmacodynamics and preliminary anti-tumor activity of a novel and potent small molecule PKMYT1 inhibitor, lunresertib.

Company Virtual Webcast Event: The Company will host a virtual investor webcast with accompanying slides for analysts and investors at 4:30 p.m. Eastern Time to further discuss the lunresertib program, including initial proof-of-concept monotherapy data from MYTHIC and an update on ongoing combination clinical trials.