Replimune presented data from its IGNYTE trial at the 2025 ASCO meeting, showing promising results for RP1, an oncolytic immunotherapy, combined with nivolumab in melanoma patients previously unresponsive to anti-PD-1 therapy. The combination therapy demonstrated a 32.9% objective response rate and a notable 15% complete response rate. Importantly, deep/visceral injections of RP1, including into the liver and lung, led to numerically higher response rates compared to superficial injections alone, while maintaining a manageable safety profile. A separate analysis confirmed the safety of RP1 handling with standard disinfection procedures.
These findings are particularly encouraging for melanoma patients who have exhausted anti-PD-1 treatment options. The demonstrated systemic activity of RP1 combined with nivolumab, evidenced by responses in both injected and non-injected lesions, opens up a new avenue for these patients. The data suggesting higher efficacy with deep/visceral injections could lead to more targeted and effective treatment strategies, especially considering the acceptable safety profile observed with liver and lung injections. This is crucial as it expands the potential reach of this therapy to address tumors in challenging locations.
The IGNYTE trial data shows a one-year overall survival rate of 75.3%, rising to 63.3% at two years and 54.8% at three years, with the median overall survival not yet reached. Notably, deep/visceral injections resulted in response rates of 42.9% (deep/visceral plus superficial injections) and 40.9% (deep/visceral only), exceeding the 29.8% response rate seen with superficial injections alone. Importantly, almost all non-injected visceral organ lesions in responding patients showed some reduction from baseline, with the majority experiencing a substantial reduction of 30% or more. The biosafety analysis further strengthens the case for RP1, confirming its localized action and the effectiveness of standard disinfection protocols.
These positive results pave the way for further development and potential regulatory approval of RP1 in combination with nivolumab. The data suggests this combination therapy could become a valuable treatment option for advanced melanoma, particularly in patients who have failed to respond to prior anti-PD-1 therapies. The findings related to deep/visceral injections could also influence future treatment protocols, potentially improving outcomes for a wider range of patients. Further research and longer-term follow-up will be crucial to fully understand the durability of responses and long-term survival benefits.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
