Adverse Events Induced by Nivolumab Plus Ipilimumab <i>vs.</i> Nivolumab Monotherapy among Cancer Patients: A Systematic Review and Meta-Analysis

A systematic review and meta-analysis of randomized controlled trials (RCTs) were performed to examine treatment-related adverse events (TRAEs) for combination of nivolumab (NIVO) and ipilimumab (IPI) compared to NIVO monotherapy among cancer patients. We searched several databases to identify relevant RCTs. Meta-analysis was performed using random-effects model. In fourteen RCTs included in the study, we found that compared to NIVO monotherapy, combination NIVO + IPI increased the risk of any grade (Risk Ratio (RR) = 1.11), and grade 3 or 4 (RR = 1.95) TRAEs. Compared to NIVO, NIVO + IPI had higher risk for any grade colitis (RR = 4.52), pneumonitis (RR = 3.06), and diarrhea (RR = 1.68).