1389P - Safety and effectiveness of immune checkpoint inhibitor therapy in patients with lung cancer and pre-existing autoimmune disease

Background

Patients with pre-existing autoimmune disease (PAD) have been largely excluded from clinical trials of immune checkpoint inhibitor (ICI) therapy in lung cancer. Real-world data is needed to explore the tolerability and activity of this drug class in this unique population.

Methods

We performed a retrospective study of patients treated with ICI therapy between 2012 and 2022 at CancerCare Manitoba (Winnipeg, Canada). Pharmacy records were used to determine ICI exposure. A review of the electronic health record was conducted to identify patients with lung cancer and PAD. The PAD group was matched (1:2) to a non-PAD group based on age and sex. The primary outcome of study was immunotoxicity, defined as either a flare of the PAD or a new immune-related adverse event (irAE). Other outcomes included objective response rate (ORR), time to treatment failure (TTF), and overall survival (OS) in the subgroup with advanced disease. Time-to-event outcomes were modeled using Kaplan-Meier analysis. Logistic regression was used to examine the association between PAD status and irAEs.

Results

1891 patients treated with ICI were retrospectively screened for PAD and a diagnosis of lung cancer. We identified 69 patients with PAD, matched to 142 patients without PAD. 66.8% had adenocarcinoma, 25.6% had squamous cell carcinoma, and 2.8% had small cell carcinoma. 49.9% of patients were treated with anti-PD-1 monotherapy. The incidence of immunotoxicity in the PAD group was 55.1% vs. 39.4% in the non-PAD group (p=0.03). The incidence of flare of the underlying PAD was 20.3%. There was no difference in incidence of high-grade irAEs between the PAD vs. non-PAD group (17% vs 24%, p=0.45). Controlling for ICI type, there was no significant association between PAD status and irAE (odds ratio=1.27, 95% CI 0.71-2.27, p=0.43). No significant differences were observed in ORR, TTF and OS in patients with advanced disease.

Conclusions

PAD status was not associated with higher incidence of irAEs in patients with lung cancer treated with ICI therapy. 1 in 5 patients with PAD experienced a flare of the underlying PAD. In those with advanced stage disease, no difference was observed in oncologic outcomes. These results should be confirmed in prospective studies.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

CancerCare Manitoba.

Funding

University of Manitoba.

Disclosure

D. Dawe: Financial Interests, Personal, Advisory Board, Compensated for advisory board attendance: AstraZeneca, Merck, Pfizer, Jazz Pharmaceuticals, Roche, Novartis, Johnson & Johnson; Financial Interests, Personal, Other, Creation of educational content: Bristol Myers Squibb; Financial Interests, Institutional, Coordinating PI, Two research grants, totaling $60,000 over the last 5 years: AstraZeneca; Non-Financial Interests, Leadership Role, Chair of the CAMO Fellowship Committee: Canadian Association of Medical Oncologists; Non-Financial Interests, Project Lead, Chair of the Small Cell Lung Cancer Working Group: Canadian Cancer Trials Group. All other authors have declared no conflicts of interest.