Replimune Reports Positive Data from IGNYTE Trial of RP1 and Nivolumab in Anti-PD1 Failed Melanoma

Replimune Group, Inc. (Nasdaq: REPL), a clinical-stage biotech firm focused on developing innovative oncolytic immunotherapies, has announced notable results from the IGNYTE clinical trial. The trial investigated the efficacy of RP1 combined with nivolumab in patients with melanoma that had previously failed anti-PD1 treatments. According to the primary analysis conducted by an independent central review, approximately one-third of the patients responded positively to the treatment, with all responses enduring beyond six months from the initial baseline.

Sushil Patel, Ph.D., CEO of Replimune, highlighted the significance of these findings, underscoring RP1's potential in a challenging therapeutic landscape with few treatment options for patients. Patel expressed optimism about their path forward, bolstered by their recent interactions with the FDA. The company intends to request a pre-BLA meeting ahead of their planned biologics license application (BLA) submission in the second half of 2024. This will pave the way for a commercial launch anticipated next year.

The IGNYTE trial's cohort for anti-PD1 failed melanoma encompassed 140 patients who received the RP1 and nivolumab combination following confirmed disease progression after at least eight weeks of prior anti-PD1 therapy, with or without anti-CTLA-4. The primary analysis was executed once all patients had been observed for at least 12 months. Topline results revealed a 33.6% overall response rate as per modified RECIST 1.1 criteria, which was the primary endpoint, and a 32.9% response rate by RECIST 1.1 criteria, an additional analysis sought by the FDA. Notably, the responses from baseline were highly durable, with a median duration exceeding 35 months.

RP1, when combined with nivolumab, demonstrated a favorable safety profile, primarily exhibiting Grade 1-2 constitutional-type side effects. These included fatigue, chills, fever, nausea, flu-like symptoms, injection-site pain, diarrhea, vomiting, headache, itching, weakness, joint pain, muscle pain, decreased appetite, and rash, with a low occurrence of Grade 3-5 events. Grade 4 adverse events were limited to individual cases of increased lipase, alanine aminotransferase, blood bilirubin, cytokine release syndrome, myocarditis, hepatic cytosis, and splenic rupture. Importantly, no Grade 5 events were reported.

Replimune plans to present the comprehensive primary analysis data, including key secondary endpoints and subgroup analyses, at an upcoming medical congress. The trial's promising results consolidate RP1's potential as a significant advancement in treating melanoma patients who have exhausted existing treatment options.

RP1 serves as Replimune’s leading product candidate, developed from a proprietary strain of the herpes simplex virus engineered to include a fusogenic protein (GALV-GP R-) and GM-CSF. This design aims to enhance tumor cell killing, immunogenicity, and activation of a systemic anti-tumor response.

Founded in 2015 and headquartered in Woburn, MA, Replimune is dedicated to transforming cancer treatment through pioneering oncolytic immunotherapies. Their RPx platform hinges on a potent HSV-1 backbone designed to induce robust immunogenic cell death and a systemic immune response, positioning their candidates to potentially synergize with a plethora of established and experimental cancer treatments. The company’s innovative approach reflects its mission to offer transformative therapies for cancer patients worldwide.