On 10 April 2026, Replimune announced that the FDA had issued a complete response letter (CRL) to its BLA for RP1 (vusolimogene oderparepvec) in combination with nivolumab for the treatment of advanced melanoma. Sushil Patel, Ph.D., CEO of Replimune said, “As we previously communicated, without timely accelerated approval, the development of RP1 will not be viable. We are devastated for our committed employees who have worked tirelessly for patients but at this point we have no choice but to eliminate jobs, including substantially scaling back our U.S. based manufacturing operations.”
Replimune criticised several aspects of the CRL, claiming that the FDA “appears to have contradicted their positions expressed at the September 2025 Type A meeting.” Replimune noted that the FDA did not repeat its previous concerns about the heterogeneity of the patient population in the relevant clinical trial, and that it acknowledged that randomizing patients to an anti-PD1 only arm in the confirmatory study was not feasible.
Replimune submitted the BLA in November 2024 under the FDA’s Accelerated Approval pathway, with the FDA also granting Breakthrough Therapy Designation.