FDA advisors backed Replimune’s oncolytic melanoma candidate RP-1, voting 10-3 that the efficacy results are evaluable and clinically meaningful. The panel’s endorsement raises the likelihood the FDA will approve RP-1, which has been twice rejected following prior submissions. The committee’s discussion centered on how the study’s single-arm design without a control group, plus comparisons between “responders” and “non-responders,” should be interpreted in the context of combination effects with a checkpoint inhibitor. Replimune argued its trial design and statistical handling supported benefit, while FDA scientists previously questioned whether the survival analysis was “interpretable” and whether the observed outcomes reflected RP-1 versus background therapy. An FDA decision is set for Aug. 2. If the agency again declines, Replimune would likely need to wait for late-cycle confirmatory trial results expected in late 2027, extending uncertainty for a targeted niche of anti–PD-1 refractory patients.