Dr Pavlick on RP1 Plus Nivolumab in PD-1 Inhibitor–Pretreated Melanoma

“What we saw was that [33.6%] of patients actually had a response. That, to us, was very surprising because we were hoping to get some response, but this was a really nice, vigorous response [rate].”

Anna C. Pavlick, BSN, MSc, DO, MBA, a professor of medicine in the Division of Hematology & Medical Oncology at Weill Cornell Medicine; as well as the founding director of the Cutaneous Oncology Program at Weill Cornell Medicine and NewYork-Presbyterian, discussed key findings from the phase 2 IGNYTE trial (NCT03767348) investigating the efficacy and safety of RP1 plus nivolumab (Opdivo) in patients with melanoma who had progressed on prior PD-1–directed therapy.

IGNYTE enrolled 156 patients with cutaneous melanoma who had previously progressed on a PD-1 inhibitor. Pavlick noted that this patient population has limited treatment options beyond clinical trials. The investigators hypothesized that the addition of RP1 to an immunotherapy agent may bolster the efficacy of the checkpoint inhibitor in patients who had progressed on immunotherapy alone, Pavlick stated.

Among 140 evaluable patients in the overall population, the overall response rate (ORR) was 33.6%. Among patients who had previously received single-agent PD-1 inhibition (n = 82), the ORR was 38.7%. Pavlick noted that these ORRs were surprising because although she and colleagues had anticipated a relatively high ORR with this combination, they had not anticipated one as robust. In these respective populations, the complete response rates were 15.05% and 21.3%, which was another surprising finding, Pavlick said. Furthermore, the partial response (PR) and stable disease (SD) rates were 18.6% and 29.3% in the overall population, respectively, and 17.3% and 26.7% in the single agent–pretreated population, respectively.

Additionally, among patients who achieved best responses of PR or SD, these outcomes were durable, she explained. Overall, the median duration of response was 21.6 months (range, 1.2+ to 43.5+), and the 1-year response rate was 70.5%.