Replimune Tudriqev Approved: First Oncolytic Virus for Melanoma After Two CRLs

The FDA granted accelerated approval to Replimune’s (REPL) Tudriqev (vusolimogene oderparepvec-wtpg, formerly RP1) on August 6, clearing the oncolytic viral immunotherapy for use with Bristol Myers Squibb’s Opdivo (nivolumab) in adults with unresectable advanced cutaneous melanoma who progressed on an anti-PD-1 regimen. It is the first oncolytic virus approved for melanoma and the first engineered herpes simplex virus product cleared for any solid tumor indication. Replimune shares closed at $12.86 on August 6, up roughly 9% from the $11.83 prior close.

The approval arrives on the company’s third attempt. The FDA issued Complete Response Letters in July 2025 and April 2026, both centered on whether the single-arm IGNYTE study could reliably distinguish Tudriqev’s contribution from nivolumab alone. Last week’s 10-3 Cellular, Tissue and Gene Therapies Advisory Committee vote, after briefing documents that called the IGNYTE data “not interpretable,” appeared to settle the question for a majority of panelists.

The IGNYTE registrational cohort enrolled 140 patients with confirmed progression on at least eight weeks of anti-PD-1 therapy. In the 91-patient efficacy-evaluable population (those with at least one non-injected lesion), Tudriqev plus nivolumab produced an objective response rate of 24.2% with a median duration of response of 14.1 months. The population was high-risk: 80% had Stage 4 disease, 54% were PD-L1 negative, and roughly a quarter had liver metastases, the strongest negative prognostic factor in melanoma. Treatment was well tolerated with mostly Grade 1-2 adverse events and no Grade 4 or 5 treatment-related events. The confirmatory Phase 3 IGNYTE-3 trial, randomizing Tudriqev plus nivolumab against physician’s choice (over 90% receiving Opdualag, BMS’s relatlimab-nivolumab combination), is already underway.

The regulatory history explains why this approval matters beyond the indication. After two CRLs over trial-design concerns, the FDA’s willingness to grant accelerated approval on a third review signals that the agency accepted the evidentiary package it had twice rejected, and that the 10-3 AdComm vote carried real weight despite the committee’s skepticism about IGNYTE’s single-arm structure. The approval carries the standard accelerated-approval condition: continued marketing depends on verification of clinical benefit in the confirmatory IGNYTE-3 trial, with results expected in 2027.

Replimune becomes a commercial-stage company for the first time. The question shifts from regulatory survival to launch execution: building a sales force, securing formulary access, and training interventional radiologists on ultrasound-guided deep visceral injections. The broad label, covering all advanced melanoma patients post-anti-PD-1 regardless of BRAF status or prior adjuvant therapy, gives the company a large addressable population. Roughly half of the estimated 105,000 new U.S. melanoma cases annually will progress on or after checkpoint inhibitor therapy.

What to watch next: the IGNYTE-3 readout. If the confirmatory trial hits its endpoint, accelerated approval converts to full approval and Tudriqev becomes a permanent fixture in the melanoma treatment sequence. If it misses, the accelerated approval is at risk. The commercial launch (pricing, payer coverage, and early uptake in the anti-PD-1 refractory niche) will provide the first real-world signal on whether the oncolytic virus platform can generate revenue beyond a token approval.

Replimune press release

What It Means for the Trade

The trade here is a launch-cash race under an accelerated-approval clock, priced at $12.86 in a company that was, until this month, pre-revenue. The two prior CRLs mean REPL traded near existential levels; the 10-3 AdComm and this approval re-rate the equity into “small commercial biotech” territory, but the market will now discount everything by IGNYTE-3 risk — and confirmatory trials in melanoma run against Opdualag, a strong standard. The 2027 readout is the second binary in a story the market thought had already resolved twice.

The near-term tells: pricing announcement (oncolytic virus economics have thin precedent — the only prior oncolytic, Imlygic, was withdrawn for commercial futility), payer coverage decisions, and early injection-site training throughput. The operational complexity is real: ultrasound-guided deep visceral injection is a skill, and launch speed depends on how fast interventional radiologists get comfortable.

Mechanism and Market Context

The biology is the story: RP1 is a modified herpes simplex virus engineered to replicate selectively inside tumor cells, lyse them, and release tumor antigens plus GM-CSF — turning the injected tumor into an in-situ vaccine. The mechanism’s demand is why the FDA was skeptical twice: a single-arm trial of oncolytic-plus-nivolumab cannot cleanly separate the virus’s contribution from re-challenged checkpoint inhibition, since some post-PD-1 melanoma patients respond to new immunotherapy combinations on their own. The 24.2% ORR with 14.1-month median duration in a heavily pre-treated, 54% PD-L1-negative, liver-metastasis-bearing population is a plausible oncolytic effect, but attribution is inferential — that’s exactly what IGNYTE-3’s randomized design exists to settle.

Risks and What Could Go Wrong

1. IGNYTE-3 confirmation failure. The base-rate risk of accelerated approvals failing confirmatory trials is elevated in single-arm-derived indications; a miss in 2027 forces withdrawal after a year of commercial build.
2. Launch execution. A first-time commercial organization selling a device-like, procedure-dependent therapy through radiologists has no clean precedent; slow uptake is the base case.
3. Opdualag headwind. The comparator in IGNYTE-3 is a formidable regimen; if it holds strongly, the confirmatory trial’s margin gets tight.
4. Cash burn vs revenue ramp. Small-cap commercialization with sales-force build, pricing negotiation, and training programs burns cash faster than a pre-revenue CRO story; watch the raise calendar.

Net: a genuine platform first with a live confirmatory fuse. Sized as an option on IGNYTE-3 plus launch execution, nothing more.