Incidence of safety events after immune checkpoint inhibitor initiation for advanced-stage non-small-cell lung cancer: a real-world study

Aim: To describe the incidence of safety events after immune checkpoint inhibitor (ICI) initiation for advanced-stage non-small-cell lung cancer. Methods: Retrospective cohort study using the HealthCore Integrated Research Database in the USA to examine the incidence of prespecified safety events of interest after ICI initiation (n = 5278). Results: The most common safety events after ICI initiation included malaise/fatigue (incidence rate [IR]: 70.7 per 100 person-years; 95% CI: 66.5-75.1) and nausea/vomiting (IR: 32.4; 30.0-34.8). Other potential immune-mediated events, including colitis (IR: 7.11; 6.26-8.04) and pneumonitis (IR: 5.47; 4.76-6.25), were less frequent but higher than after any systemic anti-cancer therapy. No safety event rate substantially increased 6 months after ICI initiation. Conclusion: This large real-world study reports the incidence of safety events with ICI regimens for advanced-stage non-small-cell lung cancer. Tweetable abstract This large real-world study describes the incidence of prespecified safety events occurring after immune checkpoint inhibitor treatment initiation for advanced-stage non-small-cell lung cancer, including potential immune-mediated events. Plain language summary Researchers wanted to investigate side effects identified with advanced lung cancer during treatment, particularly immunotherapy. To investigate these side effects, researchers examined health insurance claims records from patients who were diagnosed with advanced lung cancer between January 2010 and July 2019, and who received treatment at various clinics across the USA. Researchers identified records for 44,045 patients treated for advanced lung cancer, with 5278 being treated with immunotherapy. After patients started immunotherapy, the most commonly reported side effects were tiredness and nausea/vomiting. Other side effects possibly related to immunotherapy were inflammation of the large intestine and lung inflammation - these events were not reported very often and did not increase in frequency 6 months after start of treatment. This large real-world study provides estimates for the frequency of side effects for those treated for advanced lung cancer, and finds that there were no large increases in the occurrence of any particular side effect in the 6 months after patients started immunotherapy for advanced lung cancer.