Replimune Lays Off 200+ Employees Following Second FDA Rejection of Melanoma Treatment RP1
Key Insights
Replimune Group (search) laid off more than 200 Massachusetts employees after the FDA rejected its melanoma (search) treatment RP1 for the second time, citing inadequate clinical trial design.
The company's IGNYTE trial showed a 34% response rate with nearly two-year median response duration for RP1 combined with nivolumab in advanced melanoma (search) patients.
CEO Sushil Patel criticized the regulatory system, stating the treatment was needed by patients and failed due to systemic issues rather than drug efficacy.
Massachusetts biotechnology company Replimune Group (search) has laid off more than 200 employees following the U.S. Food and Drug Administration's second rejection of its experimental melanoma (search) treatment RP1. The layoffs, which began this week and continue through April 24, affect workers across all functions at the Woburn-based company, including employees at its manufacturing facility in Framingham.
The job cuts represent a significant portion of Replimune's Massachusetts workforce, which totaled 480 employees as of March 2025. The company initially notified the state of 63 layoffs but expanded the cuts to over 200 workers after the FDA's April 10 decision.
FDA Rejects Melanoma Treatment Twice
The layoffs follow the FDA's complete response letter rejecting Replimune's biologics license application for RP1, also known as vusolimogene oderparepvec. This marks the second time regulators have rejected the drug, following an initial refusal in July 2025.
RP1 is an oncolytic immunotherapy derived from engineered viruses designed to target and destroy tumors. The treatment was being studied in combination with the immunotherapy drug nivolumab for patients whose advanced melanoma (search) had progressed despite prior treatment.
In the company's IGNYTE clinical trial, patients showed a 34% response rate with a median response duration of nearly two years. Despite these results, the FDA rejected the application both times, citing concerns that the IGNYTE trial did not constitute an adequate and well-controlled clinical investigation.
Company Leadership Responds
"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," CEO Sushil Patel said in a statement. "A treatment desperately needed by patients will not be available. Not because the medicine failed. Because the system did."
Replimune alleged that the FDA assigned an entirely new review team to evaluate the resubmission—one that did not meet with the company during the review—and that the new team reversed positions the prior reviewers had taken.
Regulatory Timeline and Challenges
The initial FDA rejection came in June, with regulators citing issues with the clinical trial design. The decision coincided with Dr. Vinay Prasad, who has been critical of drug approvals with limited data, taking over the FDA's biologics division. However, reports indicate that Prasad had little involvement in the Replimune rejection. Prasad left the FDA in March, after Replimune resubmitted its drug for approval in October.
In a February filing with the Securities and Exchange Commission, Replimune warned that if the resubmitted application for RP1 wasn't approved, the company "might not be able to continue the development of RP1 for this indication, if at all, and we may be required to implement a restructuring plan and review our priorities across the RPx portfolio."
Broader Industry Impact
Replimune's workforce reduction reflects broader challenges facing the biotechnology sector. Watertown-based Disc Medicine disclosed plans to lay off about 20 percent of its workforce following FDA's rejection of its drug bitopertin for treating a rare blood disorder. Disc announced plans to merge with Gemini Therapeutics (search) earlier this month.
Additionally, Takeda Pharmaceuticals (search), Massachusetts' largest biopharma employer, informed the state in March of plans to lay off about 250 workers in Cambridge beginning in July.
Founded in 2015 and headquartered at 500 Unicorn Park Drive in Woburn, Replimune has focused on developing oncolytic immunotherapies for cancer (search) treatment. The company trades on NASDAQ under the ticker REPL and operates manufacturing facilities in both Woburn and Framingham.