Potential $1 Billion Seller Clears FDA Hurdle After Two Rejections

Replimune’s melanoma treatment, developed after two setbacks, has finally cleared the U.S. Food and Drug Administration (FDA) approval hurdle.

According to BioPharma Dive on the 6th (local time), the FDA granted accelerated approval to Replimune’s oncolytic virus therapy Tudriqev (active ingredient: RP1). The treatment is used in combination with Bristol Myers Squibb’s (BMS) Opdivo for patients with advanced melanoma whose cancer has progressed despite treatment with a PD-1 immune checkpoint inhibitor.

Tudriqev is a genetically engineered lytic virus administered by direct injection into tumors. The virus replicates within the tumor and destroys cancer cells, releasing immune-stimulating proteins in the process to produce a therapeutic effect.

The approval is accelerated, meaning full approval will depend on the outcome of an ongoing phase 3 clinical trial. The trial is comparing the Tudriqev-Opdivo combination with a PD-1 inhibitor or chemotherapy, with results targeted for release by the end of 2027.

In the single-arm clinical trial that supported the approval, approximately 25% of patients showed a tumor response to the Tudriqev-Opdivo combination, and the median duration of response was slightly more than 14 months.

Before the advisory committee meeting, FDA reviewers raised questions in publicly released briefing documents about Replimune’s trial design and response-assessment methods, saying it was difficult to distinguish Tudriqev’s actual effect. However, the advisory committee reversed the situation by voting to recommend approval, saying the signal observed in a patient population with few treatment options was sufficient to support approval.

The approval is expected to mark an important turning point for Replimune. The company previously warned that it could discontinue Tudriqev’s development if the treatment was rejected for a third time. Daina Graybosch, an analyst at Leerink Partners, forecast peak annual sales of $618 million for Tudriqev, while Wall Street estimates have reached as high as $1 billion.

Karim Mikhail, acting director of the FDA’s Center for Biologics Evaluation and Research (CBER), said, "The prognosis for patients with advanced melanoma who no longer respond to PD-1 blockade therapy is poor, and their options have been extremely limited," adding, "Clinicians treating these patients understand this urgency firsthand."