Real-world Prevalence of Autoimmune Disease (AD) Among Patients (pts) Receiving Immune Checkpoint Inhibitors (ICI) in ASCO’s CancerLinQ Database

ASCO Annual Meeting 2019 Presentation
Authors Li Chen, Mark S. Walker, Jizu Zhi, George Anthony Komatsoulis, Monika Jun, Edward Stepanski, Ryan Fukushima, Denise Lau, Jeremy Roberts, Brigham Hyde, Robert S. Miller, Sean Khozin, and Wendy S. Rubinstein

Background: Although pts with AD are routinely excluded from ICI clinical trials, evidence suggests they may be receiving ICI therapy once approved. We sought to understand the prevalence of AD among all pts receiving ICIs in real world clinical care, as well as in advanced non-small cell lung cancer (aNSCLC) alone, and to describe the characteristics of ICI pts with and without evidence of AD.

Methods: We conducted a retrospective, observational cohort study using statistically de-identified data from January 2011 to November 2018 in CancerLinQ, ASCO’s real-world oncology database. Adult pts who received ≥ 1 dose of an ICI and had ≥ 2 clinical visits were eligible for inclusion. A sub-analysis examining only aNSCLC pts was also carried out. To reduce the likelihood of capturing pts who may have been on a clinical trial, pts were excluded if they received the ICI prior to its first FDA approval date. AD status was determined by the presence of select ICD-9/ICD-10 codes or a medication used to treat autoimmune disease (including steroids) prior to ICI treatment start date. Symphony claims data were linked to CLQ via tokenization to build out cohorts. Characteristics of pts with and without autoimmune disease were compared using Chi-square or Fisher’s exact tests.

Results: Prevalence of AD was 23% (538/2425 pts) in the aNSCLC population and 27% (3407/12712 pts) in the all ICI patient population. Median age did not differ between AD pts and those with no evidence of AD (All ICI: 67.6 v 67.3 years; aNSCLC: 68.5 v 67.9). AD pts were more likely to be female (All ICI: 46% v 40%, p < 0.001; aNSCLC: 55% v 44%, p < 0.001). Among all ICI pts, AD pts were less likely to be Stage IV (62% v 65%) or to have melanoma (4.6% versus 8.7%) compared to pts with no evidence of AD. The most common ADs among all ICI and aNSCLC patients were glucocorticoid deficiency (6.3% and 3.9%), rheumatoid arthritis (4.2% and 5.8%), and sacroiliitis (2.7% and 3.9%), respectively.

Conclusions: This analysis of real-world data finds that a large proportion of pts receiving ICI may have pre-existing AD. Further examination is warranted to examine how AD status may impact outcomes.