Safety and efficacy of immune checkpoint inhibitors (CPI) in metastatic renal cell cancer (RCC) and urothelial cancer (UC) patients (pts) with pre-existing autoimmune disorders (AD).

Abstract

653 Background: The pivotal clinical trials of CPI generally excluded pts with AD given concern for serious exacerbations. There is limited data on the safety and efficacy of CPI in this population. Methods: We conducted a retrospective single center analysis of RCC and UC pts treated with CPI. Pts were grouped by presence or absence of AD. We catalogued the incidence of new irAEs (CTCAEv4), AD exacerbations, objective response rate (ORR, RECIST 1.1), and overall survival (OS, Kaplan Meier). Competing risk models estimated cumulative incidences of irAEs and CPI discontinuation using 6 months (mos) as a benchmark. Results: 271 RCC and 220 UC pts were identified. Median followup was 21 mos for RCC and 13 mos for UC. 25 (9%) RCC and 27 (12%) UC had pre-existing AD; most commonly dermatologic and rheumatologic. A minority (3% RCC/4% UC) had clinically active AD requiring concurrent immunomodulators. AD exacerbations occurred in 8 (32%) RCC and 12 (44%) UC; median time to exacerbation was 86 (25-270) and 27 (8-300) days, respectively. Cumulative incidence of new irAEs at 6 mos was numerically higher in RCC AD pts (50% vs 37%). CPI discontinuation and clinical outcomes were similar among AD and non-AD pts (Table). Conclusions: CPI are active in advanced RCC and UC pts with pre-existing AD. Exacerbations and new irAEs should be expected, but AD pts can experience similar outcomes and rates of drug discontinuation. Larger scale investigations are warranted. [Table: see text]