FDA approves Replimune's oncolytic virus treatment RP1 for advanced melanoma

The US Food and Drug Administration has approved Replimune's RP1 (vusolimogene oderparepvec) for the treatment of advanced melanoma, according to Stat News reporting from 6 August 2026. The approval follows two earlier FDA rejections and comes after a Phase 3 confirmatory trial programme, representing a notable outcome for both the company and patient advocacy groups that had campaigned for access to the treatment.

RP1 is an engineered herpes simplex virus-based oncolytic therapy designed to replicate selectively within tumour cells and stimulate an immune response against the cancer. The FDA's earlier rejections had centred on questions about the evidence base; the confirmatory Phase 3 data appear to have satisfied the agency's requirements.

An FDA advisory committee had voted in favour of the treatment in a session reported by Genetic Current on 31 July 2026. The approval is notable for the oncolytic virus field more broadly, as it provides a regulatory precedent for this class of immunotherapy in solid tumours. Genetic Current covered the advisory committee vote in detail on 31 July; readers seeking background on the mechanism and clinical programme should refer to that cluster.