Safety of immune checkpoint inhibitors in Chinese patients with melanoma

This study aimed to determine the tolerability of Chinese melanoma patients, particularly those with hepatitis B virus (HBV) infection, to immune checkpoint inhibitor therapy. Patients with metastatic melanoma who received anti-cytotoxic T lymphocyte-associated antigen-4 antibody (ipilimumab) or anti-programmed death 1 antibody (pembrolizumab) therapy at our hospital between August 2012 and July 2015 were retrospectively reviewed. Adverse events were evaluated according to the National Cancer Institute Common Terminology Criteria for Adverse Events, version 3.0. Twenty-three patients with advanced melanoma were included; nine and 10 patients received infusions of ipilimumab and pembrolizumab, respectively, whereas four patients received concurrent ipilimumab and pembrolizumab therapy. There was no cessation of treatment because of agent-related adverse events in any patient. Immune-related adverse events were observed in 44% (4/9), 60% (6/10), 100% (4/4), and 61% (14/23) of patients receiving ipilimumab, pembrolizumab, concomitant ipilimumab and pembrolizumab, and any treatment, respectively. The most frequent immune-related adverse events were endocrine disorders (39%, 9/23), liver function abnormalities (22%, 5/23), and dermatological events (17%, 4/23). There were no gastrointestinal reactions. Toxicities were usually mild and easily managed; only 13% (3/23) of patients had grade 3 adverse events and none experienced grade 4 events or treatment-related death. No additional toxicity nor severe hepatotoxicity was observed in 11 patients who had previous HBV infection. The recommended anti-cytotoxic T lymphocyte-associated antigen-4 and anti-programmed death 1 antibody doses were well tolerated by Chinese patients. Thus, immune checkpoint inhibitors appear to be effective and safe in metastatic melanoma patients, including those with pre-existing HBV infection.