Dr Sun on the Association of Duration of Immunotherapy and OS in NSCLC

Lova L. Sun, MD, MSCE, assistant professor of medicine, the Hospital of the University of Pennsylvania, Penn Medicine, discusses the association between duration of immunotherapy and overall survival (OS) in patients with advanced non–small-cell lung cancer (NSCLC).

A real-world study utilized data from the electronic health record–derived Flatiron Health database to further assess practice patterns surrounding the discontinuation of immune checkpoint inhibitor therapy at 2 years, and to evaluate if there was an OS benefit associated with indefinite vs fixed duration immunotherapy.

Data presented in a posted at the 2023 ASCO Annual Meeting showed that there was no statistically significant difference in OS between patients who stopped immunotherapy at 2 years vs those who continued treatment beyond 2 years, Sun begins. In patients treated with fixed-duration therapy (n = 113), the 3- and 4-year OS probabilities were 0.89 and 0.79, respectively. In the indefinite therapy group (n = 593), the 3- and 4-year OS probabilities were 0.91 and 0.81, respectively.

Another major finding of this study was that only 1 in 5 patients who were progression free discontinued treatment at 2 years. This suggests that the vast majority of patients in the United States are continuing treatment beyond 2 years in the absence of progression, Sun explains, noting that indefinite treatment could have implications on financial and medical toxicities.

Sun explains that this research was not designed to provide a definitive answer on whether patients should stop immunotherapy at 2 years. Rather, the real-world study aimed to question if stopping immunotherapy at 2 years may be a safe and a reasonable approach in the absence of randomized clinical trial data, Sun continues. Proposed randomized clinical trials could evaluate fixed-duration vs indefinite immunotherapy in a prospective setting, she expands. However, these trials would likely to take a significant amount of time to accrue patients and produce results, Sun concludes.