Repare Therapeutics Offloads PKMYT1 Inhibitor to Debiopharm in Strategic Deal

Repare Therapeutics has found a new home for its paused PKMYT1 inhibitor, lunresertib, in a deal with Swiss pharmaceutical company Debiopharm. The agreement, announced on July 15, 2025, marks a significant development in Repare's ongoing strategy to streamline its pipeline and focus on key clinical priorities.

Deal Structure and Financial Terms

Under the terms of the agreement, Debiopharm will acquire the rights to lunresertib for an upfront payment of $10 million. The deal also includes potential near-term payments of $5 million and up to $257 million in clinical, regulatory, commercial, and sales milestones. Additionally, Repare stands to receive single-digit royalties on future sales of the drug.

Strategic Implications for Both Companies

For Repare Therapeutics, this deal represents a crucial step in its recent efforts to prioritize its pipeline. CEO Steve Forte emphasized the company's focus on two ongoing phase 1 clinical trials: the LIONS trial evaluating the PLK4 inhibitor RP-1664, and the POLAR trial assessing the Polθ ATPase inhibitor RP-3467. Both trials are expected to yield readouts in the second half of 2025.

Debiopharm, on the other hand, sees significant potential in lunresertib, particularly when combined with its own WEE1 inhibitor, Debio 0123. Bertrand Ducrey, CEO of Debiopharm, expressed optimism about the combination's synergistic effects, stating, "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."

Clinical Development Plans

As part of the agreement, Debiopharm will take over the ongoing study of lunresertib in combination with Debio 0123. This study builds upon promising phase 1/1b clinical data, which suggested the potential for rapid and deep tumor regressions in certain cancer types.

The deal comes seven months after Repare had paused its plans for lunresertib, including abandoning a phase 3 trial that would have evaluated the drug in combination with Repare's ATR inhibitor camonsertib for platinum-resistant ovarian cancer. At that time, Repare had indicated it would halt further development of lunresertib unless a partner could be found.