Stopping Immunotherapy After 2 Years vs Continuing Treatment May Yield Similar Survival Outcomes in Patients With Advanced NSCLC

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Patients with advanced non–small cell lung cancer (NSCLC) may be able to stop receiving immunotherapy at 2 years as long as their cancer hasn’t progressed, according to new findings presented by Sun et al at the 2023 ASCO Annual Meeting (Abstract 9101) and simultaneously published in JAMA Oncology. The study found that there was no statistically significant difference in overall survival between patients who stopped treatment at 2 years and those who continued treatment indefinitely.


Over the past decade, the approval of immune checkpoint inhibitors has revolutionized treatment for patients with advanced NSCLC, helping to improve their survival outcomes. However, an important question has remained unanswered: how long should a patient with advanced NSCLC continue receiving immunotherapy as part of their treatment strategy?

The appropriate length of treatment remains an open question because pivotal clinical trials have used different treatment durations, and as therapies have been approved and become widely available, many patients have continued therapy beyond the 1 to 2 years tested in clinical trials. However, the longer a patient continues treatment, the higher the health-care costs—both to the patient and to the health-care system—and the higher the ongoing risk of immune-related side effects.

“We hope this data provides reassurance that stopping treatment at 2 years is a valid treatment strategy that does not seem to compromise overall survival,” explained lead study author Lova Sun, MD, MSCE, Assistant Professor of Hematology-Oncology at the Perelman School of Medicine at the University of Pennsylvania. “In the absence of definitive prospective data about the duration of therapy—which will take years to accumulate—our goal was to use real-world observational data to provide guidance on this important clinical question,” she added.

Study Methods and Results

In the new retrospective cohort study, the investigators used national electronic health records to analyze the de-identified data of 1,091 patients with advanced NSCLC who received immune checkpoint inhibitors as part of their initial treatment—either alone or in combination with chemotherapy—and whose cancer had not continued to grow. The investigators found that only about 20% of the patients stopped treatment with immunotherapy at 2 years and were considered the fixed duration group. The vast majority of the patients who continued treatment beyond 2 years were considered the indefinite duration group.

The researchers noted that the data demonstrated similar overall survival rates between the two groups—with a 79% rate of overall survival for the fixed duration group and a 81% rate of overall survival for the indefinite duration group.


“Ultimately, the field is still on the leading edge of determining the most appropriate duration for these immunotherapies that have been so effective for patients with advanced [NSCLC],” emphasized senior study author Charu Aggarwal, MD, MPH, the Leslye M. Heisler Associate Professor for Lung Cancer Excellence in the Division of Hematology-Oncology at the Perelman School of Medicine, Associate Director of Precision Oncology Innovation at the Penn Center for Cancer Care Innovation, and Physician Leader of Airways Malignancies Research at the Abramson Cancer Center at the University of Pennsylvania. “This study provides important data that we hope will help patients feel less worried about potential risks of coming off therapy and more confident if they decide to discontinue treatment after 2 years,” she concluded. 

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