Stopping immunotherapy after 2 years is practical in patients with advanced non–small cell lung cancer

For patients with advanced non–small cell lung cancer treated with frontline immunotherapy without disease progression at 2 years, real-world data suggest that it is reasonable to discontinue immunotherapy because of the comparable overall survival rates found for patients who continue immunotherapy beyond 2 years. In a study conducted to assess the optimal duration of immune checkpoint inhibitor treatment in patients with advanced non–small cell lung cancer, investigators compared 2-year overall survival between 113 patients who discontinued immune checkpoint inhibitor treatment at 2 years (a fixed duration between 700 and 760 days) and 593 patients who continued treatment beyond 2 years (an indefinite duration greater than 760 days).1 They found that there was no difference in 2-year overall survival between the two groups (79% for patients on a fixed duration and 81% for patients on an indefinite duration). After adjustments for covariates, including smoking, histologic type, and programmed death ligand 1 status, the lack of a difference in 2-year overall survival remained (hazard ratio, 1.33; 95% CI, 0.78–2.25; p = .29). “A common clinical question for patients with metastatic non–small-cell lung cancer with long-term response to immunotherapy-based treatment is how long to continue treatment,” says the lead author of the study, Lova Sun, MD, assistant professor of medicine at the Hospital of the University of Pennsylvania in Philadelphia. “Our findings provide reassurance that for patients and providers who are considering stopping at 2 years, this strategy does not appear to compromise outcomes.” Jack West, MD, MPhil, associate professor of medical oncology at City of Hope Comprehensive Cancer Center in Los Angeles, California, underscores the importance of realworld data to help to inform providers and patients on how to decide whether to continue with immunotherapy beyond 2 years. “These results mean that, ‘More is not better’ and that patients can experience lower risk of side effects, reclaim the time that would be spent coming in for treatment infusions every few weeks for additional years, and simultaneously lower costs to the health care system without any evidence that their survival is compromised,” he says. Many patients are not benefiting from the advantages of discontinuing immunotherapy, however, as indicated by another key finding of the study. “Importantly, the data reviewed in this trial also revealed the strong predisposition of oncologists and patients, in the face of ambiguity, to continue treatment beyond 2 years,” says Dr West. “Approximately four out of five patients in the real-world setting received treatment beyond the 2-year interval that is incorporated as the maximum for most clinical trials with immunotherapy.” Dr West, who also wrote an editorial accompanying the study,2 acknowledges that the findings of the study are limited because of its retrospective design, but he notes that prospective clinical trials to definitively answer the question of optimal immunotherapy duration in this setting take years, and patients and providers are seeking answers now. “These retrospective data are what we have for our clinical decision-making for the next several years,” he says.