Toxicity, disease management and outcome of treatment with immune checkpoint inhibitors by sex in patients with cancer and preexisting autoimmune disease

Female sex is associated with a higher risk for autoimmune diseases (ADs) and immune-related adverse events (irAEs) from immune checkpoint inhibitors (ICIs). While the safety of ICIs in AD cohorts has been reported, sex-segregated data on patient characteristics and outcomes are lacking. In the present study, the disease and treatment characteristics of 51 patients with cancer and preexisting AD (PAD) treated with ICIs at Bern University Hospital Cancer Center (Bern, Switzerland) between January 2017 and June 2021 were analyzed by sex. Rheumatic (n=12/27, 44.4%) and endocrine (n=11/24, 45.8%) PADs were most common among male and female patients, respectively. At the time of ICI initiation, 29.6% (n=8/27) of male and 20.8% (n=5/24) of female patients received immunosuppression for their PAD. Female patients were more likely to experience an irAE (58.3 vs. 48.1%), and less likely to encounter an exacerbation of their PAD (38.5 vs. 14.3%) compared with male patients. Multiple-site irAEs (46.2 vs. 21.4%), implication of an organ specialist for irAEs (100.0 vs. 57.1%) and use of additional immunosuppressive drugs (38.4 vs. 7.7%) were more common in male patients. IrAEs were resolved and ICIs were discontinued in 69.2% (n=9/13) and 71.4% (n=10/14) of the total male and female patients, respectively. Median progression-free survival was higher in male than female patients with irAEs (19.9 vs. 10.7 months) and without irAEs (4.4 vs. 1.8 months). The median overall survival time was higher in male than female patients with irAEs (not estimable vs. 22.5 months) and without irAEs (10.1 vs. 7.4 months). Taken together, these results suggested that sex-related differences existed regarding the clinical presentation of irAEs and treatment outcome.