Risk and survival of patients with non-small cell lung cancer and pre-existing autoimmune disorders receiving immune checkpoint blockade therapy: Survival analysis with inverse probability weighting from a nationwide, multi-institutional, retrospective study (NEJ047)

•NSCLC diagnosis within 1 year of AID diagnosis increases risk of AID flares.•The safety profiles of combination immunotherapy monotherapy were comparable.•After inverse probability weighting, ICB versus without ICB prolonged survival.•These results support the use of ICB in patients with NSCLC and pre-existing AID. The risk and survival of patients with non-small cell lung cancer (NSCLC) with pre-existing autoimmune disorders (AIDs) receiving immune checkpoint blockade (ICB) therapy have not been clearly established. This multi-institutional, retrospective cohort study was conducted in collaboration with 20 centers in Japan. In total, 229 patients with advanced or recurrent NSCLC and pre-existing AID, with or without ICB treatment from January 2010–February 2020, were included and analyzed. Among 69 patients who received ICB, 2 received two lines of ICBs with a total of 71 ICB treatments; 57 (80.3 %) and 14 (19.7 %) patients received ICB monotherapy and combination therapy, respectively. AID flares were observed in 18 patients (25.4 %, 95 % confidence interval [CI], 15.8–37.1 %) receiving ICB. AID exacerbations were more likely when NSCLC was diagnosed less than 1 year after the AID diagnosis (odds ratio 5.26 [95 % CI, 1.40–21.61]; P = 0.016). Immune-related adverse events were observed in 32 patients (45.1 %, 95 % CI, 33.2–57.3 %); 17 had grade 3 or higher. The safety profile of combination immunotherapy was not significantly different from that of the monotherapy. After inverse probability weighting, the use of ICB prolonged survival (hazard ratio 0.43 [95 % CI, 0.26–0.70]; P = 0.0006). These findings revealed a novel risk factor for AID flares following ICB treatment, that is the diagnosis of NSCLC within 1 year of AID diagnosis, and showed that ICBs may improve survival in this population. These results support the utilization of ICB in patients with NSCLC and pre-existing AID.