Meta-analysis of randomized controlled trials for the incidence and risk of fatal adverse events in cancer patients treated with ipilimumab

Background: Ipilimumab is a fully human immunoglobulin G1 monoclonal antibody that increases antitumor T-cell responses. We conducted a meta-analysis of randomized controlled trials (RCTs) to evaluate the risk of FAEs associated with ipilimumab.Methods: We searched PubMed, EMBASE, and ASCO meeting abstract up to September 2016 for RCT comparing ipilimumab with no ipilimumab on cancer patients. Incidence rates, relative risk ratios (RRs), and 95% confidence intervals (CIs) were calculated using fixed- or random effects models. The primary end point was the association of ipilimumab with FAEs. Subgroup analyses were performed according to tumor type, concurrent therapy, and dose of ipilimumab.Results: A total of 5,466 patients from 10 RCTs were included. For patients receiving ipilimumab, the overall incidences of FAEs was 0.99% (95% CI: 0.48%-1.69%). Allocation to ipilimumab therapy increased the risk of FAEs (RR=2.16, 95% CI, 1.03-4.54) significantly. Subgroup analyses reached statistical significance for prostate cancer, high dose of ipilimumab, and placebo as a control group. No evidence of publication bias was observed.Conclusions: Compared with control or placebo, ipilimumab was associated with an increased risk of FAEs in cancer patients. As ipilimumab gains greater clinical use, practitioners must be aware of the risks associated with its use.