As reported in the Journal of Clinical Oncology by Jason J. Luke, MD, FACP, and colleagues, the final prespecified analysis of distant metastasis–free survival in the phase III KEYNOTE-716 trial showed continued benefit with adjuvant pembrolizumab vs placebo in patients with resected stage IIB or IIC melanoma.
The primary analysis of the trial supported the December 2021 approval of pembrolizumab in this setting, showing significant improvements in recurrence-free and distant metastasis–free survival.
Jason J. Luke, MD, FACP
Study Details
In the trial, 976 patients aged ≥ 12 years with newly diagnosed disease who had undergone resection were randomly assigned to receive adjuvant pembrolizumab at 200 mg or 2 mg/kg up to 200 mg in pediatric patients (n = 487) or placebo (n = 489) once every 3 weeks for 17 cycles or until disease recurrence or unacceptable toxicity.
Key Findings
At the time of final analysis, median follow-up was 39.4 months (range = 26.0–51.4 months).
Median distant metastasis-free survival was not reached in either group. Events occurred in 74 patients (15.2%) in the pembrolizumab group vs 119 patients (24.3%) in the placebo group. Estimated distant metastasis–free survival at 36 months was 84.4% in the pembrolizumab group vs 74.7% in the placebo group (hazard ratio [HR] = 0.59, 95% CI = 0.44–0.79).
Median recurrence-free survival was not reached in either group. Events occurred in 117 patients (24.0%) in the pembrolizumab group vs 174 patients (35.6%) in the placebo group. Estimated recurrence-free survival at 36 months was 76.2% vs 63.4% (HR = 0.62, 95% CI = 0.49–0.79).
Among patients in the stage IIB and stage IIC subgroups, estimated 36-month distant metastasis–free survival was 86.7% vs 78.9%, respectively (HR = 0.62, 95% CI = 0.42–0.92), and 80.9% vs 68.1%, respectively (HR = 0.57, 95% CI = 0.36–0.88); estimated 36-month recurrence-free survival was 79.7% vs 66.5% (HR = 0.58, 95% CI = 0.43–0.79) and 71.4% vs 58.0% (HR = 0.65, 95% CI = 0.45–0.94).
The safety profile of pembrolizumab was reported to be manageable and consistent with previous studies.
The investigators concluded, “These results continue to support the use of pembrolizumab adjuvant therapy in patients with resected stage IIB or IIC melanoma.”
Dr. Luke, of UPMC Hillman Cancer Center and the University of Pittsburgh, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by Merck Sharp & Dohme LLC, a subsidiary of Merck & Co, Inc. For full disclosures of the study authors, visit ascopubs.org.
