Effectiveness and Safety of Immune Checkpoint Inhibitors in Cancer Patients With Autoimmune Disease: A Retrospective Cohort Study.

Although immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, patients with pre-existing autoimmune diseases (PADs) have largely been excluded from clinical trials evaluating this drug class. This study evaluates the effectiveness and safety of ICI therapy in individuals with PAD in a real-world setting. A retrospective study of patients exposed to ICI therapy between 2012 and 2019 was conducted. Patients with PAD were identified and matched to an ICI-exposed group without PAD based on age, sex, and cancer type. Primary outcomes included toxicity, time to treatment failure, overall survival, and objective response rate. The association between PAD status and outcomes was determined using Cox and logistic regression modeling. A total of 813 patients exposed to ICI therapy were identified, of which 8.2% (N=67) had a PAD. When compared with a matched cohort without PAD (N=132), there was no significant difference in the rates of new immune-related adverse events (irAEs, 42.4% in the non-PAD group vs. 47.8% in the PAD group, P=0.474). After controlling for the type of ICI, there was no significant association between PAD status and irAE (odds ratio 1.67, 95% CI: 0.9-3.21 P=0.1). There was no significant association between overall survival and PAD status (hazard ratio 1.12, 95% CI: 0.76-1.66. P=0.56) or between time to treatment failure and PAD status (hazard ratio 0.82, 95% CI: 0.6-1.12, P=0.22). There was an association between PAD status and objective response rate (odds ratio 3.28, 95% CI: 1.28-8.38, P=0.013). In summary, PAD status was not associated with enhanced toxicity when compared with patients without PAD, with similar oncologic effectiveness between these 2 groups.