Use of PD-1 pathway inhibitors among patients with non-small cell lung cancer (NSCLC) and preexisting autoimmune disorders.

Abstract

9081 Background: Since patients (pts) with NSCLC and autoimmune (AI) disease were largely excluded from immune checkpoint inhibitor clinical trials, we aimed to determine the safety of PD-1 inhibitors in NSCLC pts with a history of AI diseases. Methods: As part of a multi-center, retrospective study, we collected clinicopathologic data from pts with advanced stage IIIB or stage IV NSCLC with a history of AI disease and who received treatment with a PD-1 inhibitor as monotherapy. Qualifying AI disorders included but were not limited to: thyroiditis (excluding hypothyroidism without clear autoimmune etiology), inflammatory bowel disease, as well as rheumatologic, neurologic and dermatologic conditions. Results: We identified 46 pts with NSCLC treated with a PD-1 inhibitor who also had a history of AI disease. At the time of PD-1 inhibitor treatment initiation, 13% of pts had active AI symptoms and 19% were receiving immunomodulatory agents for their AI condition. The median period of follow up after initiation of anti-PD-1 therapy was 17.4 weeks (range 0.6-72.1 weeks). Exacerbation of the underlying AI condition occurred in 8 pts (17%). Two of these pts required steroid treatment (both for rheumatoid arthritis), and three of these pts required temporary interruption of treatment due AI disease flare. Overall, twelve (26%) pts developed at least one immune-related adverse event (irAE) unrelated to the underlying AI condition (8 grade 1-2, 4 grade 3); there were no cases of grade 4-5 irAEs. PD-1 therapy was permanently discontinued in 3 cases due to the development of an irAE (1 for grade 1 pneumonitis, 1 for grade 3 transaminitis, 1 for grade 3 diabetes insipidus). Conclusions: In pts with NSCLC and a history of AI conditions treated with PD-1 blockade, symptomatic flare of underlying AI disease was uncommon. The rate of immune-related toxicities in this population appears similar to published studies in pts without baseline AI conditions. Further analysis of pts with active AI conditions is needed to clarify the safety profile in this population.