31P Safety and efficacy of immune checkpoint inhibitors in cancer patients with pre-existing autoimmune disease: A UK tertiary cancer centre experience

Abstract

Immune check-point inhibitors (ICPi) are routinely used in cancer treatment in the United Kingdom and are associated with immune-related adverse events (irAE). Most patients with autoimmune disease (AID) are often excluded from clinical trials investigating ICPi, due to hypothetical increased risks of AID flare or severe irAE, but these risks have never been conclusively verified. We present experience using ICPi at a UK tertiary cancer centre, comparing the irAE profile and efficacy in patients with pre-existing AID to those without. This was a single centre retrospective analysis of electronic records of solid tumour patients who received treatment with an ICPi from January 2017 to December 2020. From a total of 562 patients, 15 had pre-existing AID. These were compared to those without AID in a 1:3 matched cohort for tumour-type and treatment. The AID cohort had inflammatory bowel disease (N=5), psoriasis (N=3), rheumatoid arthritis (N=2), polymyalgia rheumatica (N=2), autoimmune endocrinopathies (N=4), lupus (N=1) and sarcoidosis (N=1). 3 patients had 2 co-existing AID. All 15 patients had well controlled AID. 9 were on hormone replacement, immunosuppressive (prednisolone <10mg, n=2, mesalazine, n=1), or topical agents. 6 were not on AID treatment. The table below lists patient demographics, irAE and outcomes. 3 out of 15 AID patients had irAE possibly linked to their underlying AID (1 psoriasis, 1 RA, 1 colitis; no G3 or higher). No significant differences were found in the number of G3 or higher irAE, treatment discontinuation due to irAE, response to treatment, or survival between cohorts.Table: 31PPatient demographics, irAE and outcomesNo AID (n=45)AID (n=15)P-valueTumour type0.9698Gynaecological31Colorectal62Head & neck31Merkel cell31Urothelial62Non-small cell lung248Immunotherapy agent>0.9999Atezolizumab31Pembrolizumab279Durvalumab31Nivolumab62Ipilimumab and nivolumab62Treated under clinical trial0.8686Yes134No3211Total number of irAEs0.569102191175271Grade 3-5 irAEs0.42Grade 3 or 481Grade 510Best response0.1044Stable disease51Mixed response51Complete or partial response185Progressive disease144 Open table in a new tab Exacerbation of pre-existing AID was infrequent and did not result in severe toxicity. Patients with well-controlled AID could be considered for entry in clinical trials involving ICPi.