Immune Checkpoint Inhibitor Is Associated with Improved Survival in Advanced Non-small Cell Lung Cancer Occurring in Patients with Autoimmune Disease

The use of immune checkpoint inhibitors (ICIs) has revolutionized the treatment of advanced non-small cell lung cancer (NSCLC). However, clinical trials often exclude those with a history of autoimmune diseases (ADs) because of concerns regarding immune-related adverse events. Therefore, the efficacy of ICIs in advanced NSCLC patients with ADs should be evaluated. This study used administrative claims data from advanced treatment centers in Japan and identified patients with advanced NSCLC who began chemotherapy between December 2016 and January 2023. The patients were divided into four groups based on the presence of ADs and types of chemotherapy received. The association between ICI therapy and overall survival in the subgroups with or without ADs, and the association between the presence of AD and overall survival in patients who received ICI therapy and conventional chemotherapy, were analyzed using Cox proportional hazard regression, including therapy and presence of ADs and their interaction as covariates. These results were obtained using the inverse probability of treatment weighting. ICI therapy had a hazard ratio (95% confidence interval) for death in the subgroup of AD and non-AD patients of 0.88 (0.84-0.92) and 0.83 (0.71-0.97), respectively (p = 0.459 for interaction). For some specific ADs, including type 1 diabetes mellitus, the association between ICI therapy and decreased mortality was not observed. In conclusion, our study showed comparable associations between ICI therapy and reduced mortality in AD and non-AD subgroups of patients with advanced NSCLC. However, therapy strategies tailored to each AD type and thorough discussions regarding the risk-benefit profile are crucial.