FDA analysis of patients with baseline autoimmune diseases treated with PD-1/PD-L1 immunotherapy agents

3018 Background: With FDA approval of three novel agents targeting the PD-L1/PD-1 checkpoint pathway in multiple tumor types, use of these agents in the clinical setting is becoming increasingly common. However, little is published on their use in patients with a history of autoimmune diseases. We therefore aimed to collect safety data on patients with a history of autoimmune diseases treated with PD-1/PD-L1 immunotherapy agents in a clinical trial setting. Methods: Data on patients with a history of autoimmune disease were collected for four different PD-1/PD-L1 immunotherapy agents. Information collected included name of autoimmune disease, corticosteroid dependency at baseline, duration of dosing, immune-related adverse events (iRAEs) and worsening of underlying autoimmune disease. Results: In total, 552 patients enrolled in 22 clinical trials of PD-1/PD-L1 immunotherapy agents were identified with a history of autoimmune disease. None were known to be dependent on systemic corticosteroids at baseline. The most common autoimmune diseases identified were thyroid disorder (n = 188), psoriasis (n = 70), and vitiligo (n = 44). For the four agents identified, mean duration of dosing was 183, 187, 196, and 145 days. Worsening of underlying autoimmune disease occurred in 16%, 6%, 13% and 6%. There were two grade 4 cases of hyperglycemia in patients with diabetes, three cases each of grade 3 AEs related to the underlying disorder in patients with psoriasis, interstitial lung disease, and hypothyroidism, and one grade 3 AE in a patient related to ankylosing spondylitis.For two of these agents, data were available on the development of grade 1-4 irAEs (per investigator) that required treatment with systemic steroids, which occurred in 8% and 9% of patients. Conclusions: Clinical trial data demonstrates relative safety of the use of PD-1/PD-L1 immunotherapy agents in patients with a history of autoimmune disease compared to their use in patients without such history. No consistent pattern of worsening of baseline autoimmune disease was identified. These results should be interpreted with caution, as diagnostic method and clinical manifestations of reported baseline autoimmune conditions are not known.