FDA Approves Second Indication for Keytruda in the Treatment of Melanoma
On February 15, 2019, the FDA approved pembrolizumab (Keytruda; Merck) for the adjuvant treatment
of melanoma with involvement of lymph node(s) after a complete resection. This is the second melanoma-related indication for pembrolizumab, which was previously approved by the FDA for the treatment of patients with unresectable or metastatic melanoma.
This latest approval was based on a phase 3, randomized, double-blind, placebo-controlled clinical trial of 1019 patients with completely resected stage IIIA, IIIB, or IIIC melanoma. Patients were required to have complete resection of the melanoma with negative margins, lymph node dissection, and—if indicated—completion of radiotherapy within 13 weeks before the start of treatment. Patients were randomized in a 1:1 ratio to pembrolizumab 200 mg every 3 weeks or placebo for up to 1 year until disease recurrence or unacceptable toxicity. The study’s primary end point was recurrence-free survival.
Results showed pembrolizumab-treated patients achieved significantly longer recurrence-free survival (hazard ratio, 0.57; 95% confidence interval, 0.46-0.70; P <.001). The median recurrence-free survival was not reached for the pembrolizumab group, whereas the median recurrence-free survival in the placebo group was 20.4 months. When compared with placebo, pembrolizumab showed a recurrence-free survival benefit regardless of tumor PD-L1 expression.
The most common (≥10%) adverse events reported with pembrolizumab were diarrhea, pruritus, nausea, arthralgia, hypothyroidism, cough, rash, asthenia, influenza-like illness, weight loss, and hyperthyroidism.