Repare Therapeutics Inc. announced the first patient has been dosed in the Company?s Phase 1 LIONS (PLK4 Inhibitor in Advanced Solid Tumors) clinical trial evaluating RP-1664, a potential first-in-class, highly selective, oral polo-like kinase 4 (PLK4) inhibitor, for the monotherapy treatment of adult and adolescent patients enriched for TRIM37-high solid tumors. The LIONS clinical trial (NCT06232408) is a first-in-human, multicenter, open-label Phase 1 study to investigate safety, pharmacokinetics, pharmacodynamics and the preliminary efficacy of RP-1664. The clinical trial is expected to enroll approximately 80 patients with molecularly selected advanced solid tumors, including those with gain or amplification of TRIM37, among other genetic alterations.

The primary endpoints are to determine the safety, tolerability, dose and schedule of RP-1664 and assess any early antitumor activity.