Disparities in adverse events during cancer immunotherapy

Immune-related adverse events (irAEs) pose substantial management challenges for patients with cancer treated with immune checkpoint inhibitors, but such events may vary between ethnic and racial groups. Here we utilized data from several large-scale sources, including ClinicalTrials.gov, a nationwide health insurance database and electronic health records, to investigate the differential odds of irAEs among racial groups. Clinical trial reporting revealed limited information regarding race distribution in irAEs; where such information was reported, substantial variations in irAE occurrence rates were observed among racial groups after PD-(L)1 treatment. Black patients had higher odds of developing overall irAEs than Hispanic patients (odds ratio (OR) 1.08, 95% confidence interval (CI) 1.01–1.15), whereas Asian patients had lower odds than white patients (OR 0.89, 95% CI 0.81–0.97). Black patients showed higher odds of musculoskeletal and connective tissue disorders (OR 1.44, 95% CI 1.30–1.60) and arthritis (OR 2.27, 95% CI 1.92–2.68) compared with Asian patients. These findings show the importance of considering racial differences in the occurrence and severity of irAEs to optimize immune checkpoint inhibitor therapy and reduce disparities in healthcare. An analysis of almost half a million clinical trials, including 7,274 immune checkpoint inhibitor-related cancer trials, found that 87% lack information on race and ethnicity, while disparities were found for many adverse events.