US FDA approves Replimune's skin cancer drug after prior rejections

An average course of therapy will be priced at $450,000 and is expected to ship in about 60 days, the company said.

RP1 will compete against Iovance Biotherapeutics' IOVA.O Amtagvi, approved in 2024 for the same condition but which requires major surgery to harvest tumor tissue.

"With no compelling and widely accessible option in PD-1 relapsed melanoma, and a relatively benign safety profile for RP1 + nivolumab, we expect real commercial uptake for RP1," said Leerink Partners analyst Daina Graybosch ahead of the approval.

The agency's decision was based on data that showed the combination treatment led to tumors shrinking or disappearing for 24.2% of patients, with a median duration of response of 14.1 months.

Cantor Fitzgerald analyst Li Watsek estimates unadjusted peak U.S. sales of $708 million by 2040 for the combination treatment.

The decision marks a major milestone for Replimune, whose third attempt at approval comes after the FDA twice declined the treatment, citing the single-arm IGNYTE study's lack of a control group and insufficient evidence of the drug's effectiveness.

The approval follows the regulator's panel of advisors who last month voted 10 to three that the drug's trial data were evaluable and showed clinically meaningful benefit.

RP1 is a genetically modified herpes virus that, when injected directly into tumors, infects and kills cancer cells while alerting the immune system to attack the cancer elsewhere in the body.

The U.S. Food and Drug Administration has approved Replimune's REPL.O drug for a difficult-to-treat form of skin cancer, the company said on Thursday, giving the biotech firm its first marketed product after multiple regulatory setbacks.