Replimune has announced the first patient in the Phase III melanoma trial with its lead immunotherapy RP1 or vusolimogene oderparepvec has been dosed and randomised.

The IGNYTE-3 study (NCT06264180) will investigate the use of RP1 plus Bristol Myers Squibb’s PD-1 inhibitor Opdivo (nivolumab) for patients with advanced melanoma who have progressed on anti-PD1 and anti-CTLA-4 therapy, or who are ineligible for anti-CTLA-4 therapy.

Massachusetts-based biotech Replimune’s CMO Kostas Xynos stated that the trial will serve to, “advance of our planned BLA submission of RP1 in advanced melanoma later this year”.

In spite of slowing research, the wider oncolytic virus-based market has been projected to grow from $114mn in 2023 to $2.4bn in 2029 according to GlobalData analyst Kevin Marcaida. Marcaida expects that within this period, Replimune’s RP1 could claim a 74% market share.

The IGNYTE-3 trial comes as Replimune continues a downward financial trend. Despite announcing $100m in private placement funding in June 2024, Replimune’s stock price fell 48.24% during the past year, as per Yahoo Finance. In its 2024 annual report, the company reported $215.8m in losses, compared to $174.3m in FY 2023.

In IGNYTE-3, Replimune plans to enrol 400 patients to compare this treatment against physician’s choice therapies, measuring as primary endpoint overall survival, in addition to key secondary endpoints progression-free survival and objective response rate.

RP1 is Replimune’s lead product candidate, based on their proprietary strain of herpes simplex virus engineered with fusogenic protein GALV-GP R^- and granulocyte-macrophage colony-stimulating factor (GM-CSF). It is intended to both maximise anti-tumour potency and stimulate the body’s own immune response against tumours.

Melanoma is the 5^th most common cancer in the US, with an estimated 100,000 new cases and 8,000 deaths in 2024. Current standard therapy relies on an immune checkpoint blockade. However, around half of patients’ cancers do not respond to this treatment, after which therapeutic options are limited.

GlobalData projects that RP1 could enter the US market in 2026 earning $16mn for Replimune, rising to $318mn by 2030. It would compete with melanoma treatments from Bristol-Myers Squibb, Pfizer, Merck, and Roche among others.

GlobalData is the parent company of Pharmaceutical Technology.

Development of melanoma therapies has been declining in prior years, potentially leaving the market open to innovative therapies like RP1.

"Replimune kickstarts Phase III melanoma trial studying RP1 immunotherapy" was originally created and published by Pharmaceutical Technology, a GlobalData owned brand.