Repare Therapeutics Licenses PKMYT1 Inhibitor Lunresertib to Debiopharm in $267M Deal
Key Insights
Repare Therapeutics has entered into an exclusive worldwide licensing agreement with Debiopharm (search) for lunresertib, a first-in-class PKMYT1 (search) inhibitor targeting difficult-to-treat solid tumors (search).
The deal includes $10 million upfront payment and up to $257 million in potential milestones, with Debiopharm (search) taking over development activities and the MYTHIC study.
Lunresertib has shown promising Phase 1/1b clinical data, particularly in combination with Debio 0123, a WEE1 (search) inhibitor, demonstrating potential for rapid tumor regressions.
Repare Therapeutics Inc. has entered into an exclusive worldwide licensing agreement with Swiss biopharmaceutical company Debiopharm (search) International S.A. for lunresertib, a first-in-class precision oncology PKMYT1 (search) inhibitor. The agreement, announced on July 15, 2025, represents a significant strategic move for the clinical-stage precision oncology company as it refocuses its development priorities.
Deal Structure and Financial Terms
Under the licensing agreement, Repare will receive a $10 million upfront payment and is eligible to receive up to $257 million in potential clinical, regulatory, commercial, and sales milestones, including up to $5 million in potential near-term payments. The company will also receive single-digit royalties on global net sales of lunresertib.
Debiopharm (search) will assume sponsorship of the MYTHIC study and take over existing and future development activities related to lunresertib. This builds upon an existing collaboration between the two companies established in January 2024 to explore the synergy between lunresertib and Debio 0123, a potential best-in-class, brain penetrant and highly selective WEE1 (search) inhibitor.
Clinical Promise and Combination Therapy
Lunresertib has demonstrated encouraging results across multiple clinical trials in difficult-to-treat solid tumors (search). The drug's mechanism as a PKMYT1 (search) inhibitor represents a novel approach to precision oncology, targeting genomic instability pathways in cancer cells.
"Based on very promising Phase 1/1b clinical data, we believe the combination of lunresertib and Debio 0123 is highly synergistic and could potentially drive rapid and deep tumor regressions," said Bertrand Ducrey, CEO of Debiopharm (search). "We believe the synthetic lethality approach of lunresertib in combination with Debio 0123 will allow us to bring this innovative precision therapy to patients with difficult to treat cancers."
Strategic Refocus on Core Pipeline
The licensing deal allows Repare to concentrate resources on advancing its two ongoing Phase 1 clinical trials. Steve Forte, President, CEO, and CFO of Repare, stated, "Our recent business development efforts have continued to enable Repare to focus on the advancement of our clinical priorities and sustained value creation. We remain focused on two ongoing Phase 1 clinical trials with readouts expected in the second half of 2025."
POLAR Trial
The POLAR clinical trial is a multicenter, open-label, dose-escalation Phase 1 study investigating RP-3467, a small molecule inhibitor of polymerase theta (search) (Polθ). This synthetic lethality target is associated with BRCA mutations and other genomic alterations. The trial evaluates RP-3467 alone or in combination with olaparib in adults with locally advanced or metastatic epithelial ovarian cancer (search), metastatic breast cancer (search), metastatic castration-resistant prostate cancer (search), or pancreatic adenocarcinoma (search). Topline safety, tolerability and early efficacy data are expected in the third quarter of 2025.
LIONS Trial
The LIONS clinical trial is a first-in-human, multicenter, open-label Phase 1 study designed to investigate RP-1664, a first-in-class, highly selective, oral inhibitor of Polo-like kinase 4 (PLK4 (search)). This synthetic lethality target is associated with TRIM37 overexpression. Initial topline safety, tolerability and early efficacy data from the Phase 1 LIONS clinical trial are expected in the fourth quarter of 2025.
Synthetic Lethality Approach
Repare's strategy centers on synthetic lethality, an approach that targets cancer cells with specific genetic vulnerabilities while sparing normal cells. The company has developed highly targeted cancer therapies focused on genomic instability, including DNA damage repair pathways. This approach enables the development of precision therapies that can selectively target tumors with particular genetic signatures.
The agreement with Debiopharm (search) supports Repare's mission to develop highly targeted cancer therapies and represents a strategic move to maximize the potential of lunresertib while allowing the company to focus on its core pipeline assets.