FDA Blocks Replimune’s 140-Patient Melanoma Drug Bid as Trial Design Sparks Political Scrutiny
Updated
Updated · CBS New York · May 15
FDA Blocks Replimune’s 140-Patient Melanoma Drug Bid as Trial Design Sparks Political Scrutiny
10 articles · Updated · CBS New York · May 15
RP1 was denied accelerated approval after the FDA said Replimune’s 140-patient melanoma study lacked a control arm, leaving regulators unconvinced the benefit came from the drug rather than Opdivo.
One-third of trial participants saw tumors shrink or disappear, and some doctors said the therapy could help roughly 2,000 to 2,500 U.S. patients a year if the results hold.
Replimune had been warned in July to change its development plan, but argued a control arm using Opdivo alone would be unethical because enrolled patients had already stopped responding to similar drugs.
The rejection has already forced Replimune to cut more than half its staff and close some operations, raising doubts about whether it can finance the larger confirmatory trial.
Under Commissioner Marty Makary, critics say the case has become a symbol of an FDA whose standards look increasingly unpredictable after 4,000 staff cuts and politically charged interventions in approvals.
With the FDA's old guard gone, will it become easier or harder to get new life-saving drugs approved?
After a chaotic year and a leadership void, can the FDA restore trust in its drug approval process?
Replimune’s RP1 Shows 32.9% ORR in Advanced Melanoma, But FDA Rejection in 2026 Triggers Industry and Patient Outcry
Overview
In 2026, the FDA rejected Replimune’s application for its melanoma drug RP1, stating the data was insufficient to prove effectiveness. This decision created major uncertainty for Replimune, whose future depended on RP1’s approval, and led the company to explore strategic alternatives. The rejection sparked debate about unmet medical needs and data quality, while analysts quickly downgraded Replimune’s outlook. The event also triggered wider scrutiny of the FDA’s approval process for similar drugs, highlighting growing industry concerns about regulatory unpredictability and its impact on innovation and investment in the biotech sector.