Repare Therapeutics Inc. ("Repare" or the "Company") (NASDAQ:RPTX), a leading clinical-stage precision oncology company, today announced the first patient has been dosed in the Company's Phase 1 (POLAR) clinical trial evaluating RP-3467, a Polθ ATPase inhibitor, alone and in combination with the poly-ADP ribose polymerase (PARP) inhibitor, olaparib. RP-3467 is Repare's fourth clinical program.

"RP-3467, our potential best-in-class Polθ ATPase inhibitor, has demonstrated highly compelling preclinical results, including complete and durable tumor regressions in combination with olaparib, the leading PARP inhibitor, with no additive toxicities. This combination is designed to meaningfully improve patient outcomes by mitigating PARP inhibitor resistance, a significant area of high unmet medical need," said Maria Koehler, MD, PhD, Executive Vice President and Chief Medical Officer of Repare. "In addition, Repare's previously reported data established the potential for RP-3467 to improve efficacy and limit toxicity in combination with radioligand therapy and chemotherapy-bearing antibody drug conjugates (ADCs), and we look forward to exploring those areas."

The POLAR clinical trial (NCT06560632) is a multicenter, open-label, dose-escalation Phase 1 clinical trial to investigate the safety, pharmacokinetics, pharmacodynamics, and preliminary clinical activity of RP-3467 alone or in combination with the PARP inhibitor, olaparib, in adults with molecularly selected advanced solid tumors. The study is expected to enroll approximately 52 patients with locally advanced or metastatic epithelial ovarian cancer, metastatic breast cancer, metastatic castration-resistant prostate cancer, or pancreatic adenocarcinoma. The primary objectives of the study are to assess the safety and tolerability of RP-3467 alone and in combination with olaparib, and to define a preliminary recommended Phase 2 dose of RP-3467 in combination with olaparib.