Immune checkpoint inhibitor use in cancer patients with a pre-existing history of autoimmune disorders.

Abstract

100 Background: Patients with a history of autoimmune disorders (AID) were generally excluded from immune checking inhibitor (CPI) trials because of concerns that these individuals might be at greater risk for developing serious immune-related adverse events (irAEs). This presents a knowledge gap, because a significant proportion of cancer patients also carry a diagnosis of AID. Methods: We retrospectively collected data from patients with AID treated with CPI at a single institution. irAEs were assessed using the CTCAEv5 criteria. Response was assessed using RECIST v1.1. Results: Of 47 cancer patients with a broad spectrum of malignancies and AIDs, 45% had active AID symptoms at the time of CPI initiation, of which 19% were on steroid-sparing agents (SSAs), 11% were on steroids, and 9% were on simultaneous steroids and SSAs. A total of 12 patients (25%) developed an AID flare, of which 100% were grade 1 or 2. Of these patients, 11 required systemic steroids, with 6 patients (55%) requiring greater than 12 weeks of oral steroids, and 3 patients required discontinuation of their CPI. Conventional irAEs developed in 10 patients (21%), of which 4 patients required systemic steroids, and 3 patients (27%) required discontinuation of their CPI. Efficacy outcomes for these patients, including radiographic response, will be available at time of data presentation. Conclusions: AID exacerbations or new irAES occurred in 25% and 21% of patients with a history of AID respectively, and were generally manageable. Only a minority of patients required cessation of their CPI due to toxicity.