Paul Nghiem, MD, PhD, University of Washington Medical Center, Seattle, WA, discusses the updated results of the JAVELIN Merkel 200 (NCT02155647) and KEYNOTE-017 (NCT02267603) trials. JAVELIN Merkel 200 investigated the efficacy of avelumab in patients with previously treated merkel cell carcinoma (MCC). After five years of follow-up, trial data shows that avelumab monotherapy led to meaningful long-term overall survival in a subset of patients with MCC whose disease had progressed after chemotherapy and supports its role as a standard of care treatment option. The Phase II multicenter KEYNOTE-017 study assessed first-line pembrolizumab for advanced MCC. With three-year survival data, this trial represents the longest available follow-up of any first-line anti-PD-1/PD-L1 therapy in MCC and demonstrates durable progression-free survival and overall survival in a proportion of patients. This interview took place at the American Society of Clinical Oncology (ASCO) 2021 Virtual Meeting.
Transcript (edited for clarity)
The JAVELIN 200 Merkel trial is now reporting on results from greater than five years. So it’s been a while. This was a very exciting trial when it started. It was the first ever positive trial in Merkel cell carcinoma. And the company started with the concept, and we started with the concept that the greatest need was after initial chemotherapy. So the folks after who had “failed” chemotherapy really had no good options...
The JAVELIN 200 Merkel trial is now reporting on results from greater than five years. So it’s been a while. This was a very exciting trial when it started. It was the first ever positive trial in Merkel cell carcinoma. And the company started with the concept, and we started with the concept that the greatest need was after initial chemotherapy. So the folks after who had “failed” chemotherapy really had no good options. And when you look at three prior historical control sets of people who progressed after chemotherapy and got more chemotherapy, not a single patient from three separate cohorts was alive one year later. So more chemo after failed chemo in Merkel is a disaster, and that was radically different. I believe it was about 50% alive as compared to zero with immunotherapy.
And now at five years, it’s still about a third alive where not a single person with more chemotherapy was alive at one year. So it’s one of the most striking curves I’ve ever seen in oncology of before and after. But again, now the field has changed and we can talk a little bit about KEYNOTE-17 as well, which is the pembrolizumab first-line. So not chemorefractory, but first-line data. And that now is reporting greater than three-year survival data. And that’s still at around half-alive kind of thing at multiple years. And so it’s a higher number than if you get chemotherapy first. We do broadly think the efficacy between anti-PD-1 and anti-PD-L1 in Merkel is very similar. Response rates in the first line, approximately 60%, give or take, 10 or 15, and I think that that’s mostly noise.
The bottom line on those two big first trials in Merkel cell carcinoma is it’s better to do first line. And similarly, first-line nivolumab has better numbers than second or third line, of course. Your chance of being alive at a number of years after is enormously better than it used to be with chemotherapy.