Safety of pembrolizumab for resected stage III melanoma

Introduction Patients with resected stage III melanoma have a heterogeneous prognosis with an especially high risk of relapse for patients with stage IIIB, IIIC and IIID according to the 2018 classification inAJCC Cancer Staging Manual, 8(th)edition (AJCC-8). Ipilimumab was the first immune checkpoint inhibitor (ICI) to show prolonged overall survival (OS) but at the cost of high toxicity. Pembrolizumab and nivolumab are inhibitors of programmed cell death 1 (PD-1) and showed prolonged relapse-free survival (RFS) in patients with resected stage III melanoma at high risk of relapse compared to placebo and ipilimumab, respectively. Areas covered The aim of this article is to review the mechanisms of action, pharmacokinetics and safety data of pembrolizumab in resected stage III melanoma and to compare its safety profile to other immune checkpoint inhibitors for the same indication. Expert opinion Pembrolizumab as adjuvant therapy of resected stage III melanoma showed an acceptable safety profile, which is comparable to that in advanced melanoma. However, it caused one death. There is uncertainty about its benefits in AJCC-8 stage IIIA melanoma patients. Additionally, caution is required since OS and long-term safety data are not available yet.