BackgroundDeciphering the correlation between immune-related adverse events (irAEs) categorized by organ system class and clinical benefit of immunotherapy is critical for clinical practice. The aim of this study is to investigate the incidence rates of irAEs and their correlations with objective response rate (ORR) in patients with advanced solid tumours treated with nivolumab (NIVO) or nivolumab plus ipilimumab (NIVO+IPI).MethodsPubMed, Embase and Cochrane library were searched for eligible studies from January 1st, 2000 to May 1st 2019. Published clinical trials on NIVO or NIVO+IPI with reported irAEs were included. Logit transformation of the irAE incidences was applied for the generation of pooled estimate and Pearson correlation coefficient was calculated to evaluate the correlation between irAE and ORR.Results48 clinical trials involving 7936 patients treated with NIVO or NIVO+IPI were included. Compared to NIVO, NIVO+IPI led to more all-grade and grade 3 or higher irAEs categorized by system organ class (P < 0.05). The ORR of NIVO was positively correlated with the incidence rate of skin (r = 0.79, P < 0.001), gastrointestinal (r = 0.56, P = 0.006) and endocrine irAEs (r = 0.44, P = 0.05), but not hepatic, pulmonary and renal irAEs. The ORR of NIVO+IPI was positively correlated with the incidence rate of skin (r = 0.54, P = 0.04), and gastrointestinal irAEs (r = 0.60, P = 0.02), but not endocrine, hepatic, pulmonary and renal irAEs.ConclusionThis meta-analysis summarizes the incidence rates of irAEs in patients with advanced solid tumours treated with NIVO or NIVO+IPI, and uncovers their correlations with ORR across multiple neoplasms. These findings highlight the potential of irAE to reflect response to NIVO or NIVO+IPI.