Real-World Analysis of Post-Progression Treatment Patterns and Outcomes for EGFR Mutation-Positive Patients Treated with First-Line Osimertinib.

Introduction: The use of osimertinib in the first-line (1L) setting is an effective treatment option for sensitizing EGFR-mutations (EGFRm+) and has significantly altered the standard of care practice for EGFRm+ disease in Canada. Unfortunately, acquired resistance to osimertinib is almost universal, and outcomes are disparate. Post-progression treatment patterns and the outcome of real-world Canadian EGFRm+ patients receiving 1L osimertinib were the focus of this retrospective review. Methods: The Glans-Look Lung Cancer Research database was used to identify and collect demographic, clinical, treatment, and outcome data on EGFRm+ patients who received 1L osimertinib in the Canadian province of Alberta between 2018 and 2022. Results: A total of 150 patients receiving 1L osimertinib were identified. In total, 86 developed progressive disease, with 56 (65%) continuing systemic therapy, 73% continuing osimertinib, and 27% switching to second-line (2L) systemic therapy. Patients were similar both in clinical characteristics at 1L osimertinib initiation and patterns of treatment failure at progression; those continuing 1L osimertinib post-progression had a longer time to progression (13.5 vs. 8.8 months, p = 0.05) and subsequent post-osimertinib initiation survival (34.7 vs. 22.8 months, p = 0.11). Conclusions: The continuation of osimertinib post-progression is an effective disease management strategy for select real-world EGFRm+ patients, providing continued clinical benefit, potentially due to different underlying disease pathogenesis.

Immune-Related Adverse Events and Survival Among Patients With Metastatic NSCLC Treated With Immune Checkpoint Inhibitors.

Importance: Immune-related adverse events (irAEs) secondary to immune checkpoint inhibitor (ICI) therapy reportedly improve overall survival (OS) in patients with non-small cell lung cancer (NSCLC). However, studies have been small and the association between irAE severity and OS remains poorly defined. Objective: To examine the association between irAEs and their severity with OS in patients with locally advanced or metastatic NSCLC receiving ICIs. Design, Setting, and Participants: This retrospective observational cohort study included patients with NSCLC receiving ICIs between March 1, 2014, and November 30, 2021, with follow-up until March 31, 2023. Data analysis was completed April 26, 2023. The Alberta Immunotherapy Database, a provincial, multicenter cohort, was used to capture data from patients receiving ICIs in Alberta, Canada. Participants included 803 patients 18 years or older who received at least 1 cycle of ICI (alone or with chemotherapy), agnostic to treatment line. Exposure: Developing an irAE mandating delay or discontinuation of ICI therapy and/or systematic corticosteroids for management of toxic effects (hereinafter referred to as clinically meaningful irAEs). Main Outcomes and Measures: The primary outcome was association between irAEs and OS according to Kaplan-Meier analysis. Clinically meaningful irAEs were identified. Patients with poor prognosis (survival <3 months) who may have died prior to irAE development were excluded from OS analysis, mitigating immortal time bias. Adjusted Cox proportional hazards regression analyses ascertained variables associated with OS. Results: Among the 803 patients included in the analysis, the median age of patients with irAEs was 69.7 (IQR, 63.1-75.2) years and the median age of those without irAEs was 67.5 (IQR, 60.4-73.3) years, with comparable sex distribution (139 of 295 men [47.1%] and 156 of 295 women [52.9%] with irAEs vs 254 of 505 men [50.3%] and 251 of 505 women [49.7%] without irAEs). Mitigating immortal time bias (n = 611), irAEs were associated with OS (median OS with irAEs, 23.7 [95% CI, 19.3-29.1] months; median OS without irAEs, 9.8 [95% CI, 8.7-11.4] months; P < .001). No OS difference was associated with treatment in hospital vs as outpatients for an irAE (median OS, 20.8 [95% CI, 11.7-30.6] vs 25.6 [95% CI, 20.1-29.8] months; P = .33). Developing irAEs remained associated with OS in the total cohort after Cox proportional hazards regression with known prognostic characteristics (hazard ratio, 0.53 [95% CI, 0.40-0.70]; P < .001). Conclusions and Relevance: In this cohort study of 803 patients with locally advanced or metastatic NSCLC receiving ICIs, developing a clinically meaningful irAE was associated with improved OS. This association was not compromised by hospitalization for severe toxic effects. Whether and how ICI therapy resumption after an irAE is associated with OS warrants further study.