- Front-line pembrolizumab was associated with 56% objective response rate (ORR) and 24-month OS of 68.7% in a multicenter, phase 2 trial of 50 patients with advanced Merkel cell carcinoma (MCC; Cancer Immunotherapy Trials Network-09/Kenote-017).
Why this matters
- Pembrolizumab yielded better responses and longer survival than expected with conventional front-line chemotherapy.
- The ORR to pembrolizumab was 56% (24% complete response and 32% partial response).
- The ORR was 59% in virus-positive tumors and 53% in virus-negative tumors (P=.765).
- 24-month PFS was 48.3%; median PFS was 16.8 months.
- 24-month OS was 68.7%; median OS was not reached.
- 28% of patients experienced grade 3+ treatment-related adverse events
- 14% of patients discontinued because of treatment-related adverse events
- 1 patient experienced treatment-related mortality.
- 50 patients with advanced MCC with Eastern Cooperative Oncology Group performance status 0/1 and naive to systemic therapy received pembrolizumab 2 mg/kg every 3 weeks for up to 2 years.
- Funding: National Cancer Institute; MCC Patient Gift Fund at University of Washington; Kelsey Dickson MCC Challenge Grant from the Prostate Cancer Foundation; Merck & Co., Inc., Kenilworth, NJ, USA.
- Small patient sample size.
- No control population.