Observed versus modelled lifetime overall survival of targeted therapies and immunotherapies for advanced non-small cell lung cancer patients – A systematic review

Outcomes used for the effectiveness (median) and cost-effectiveness (mean) on overall survival (OS) are different and can vary from one another. Therefore, we compared median and mean OS gains of targeted therapies and immunotherapies for stage IIIB/IV Non-small cell lung cancer and explored underlying aspect. Eligible trials were searched in PubMed, survival curves were digitized, and parametric survival models fitted to model the mean OS. Twenty-seven trials were found for targeted therapies (n = 17) and immunotherapies (n = 10). Differences between median and mean OS gains in months ranged from −2.8 to 6.8 and −4.9 to 0.3 for two different subgroups of targeted therapies, and −2.4 to 11.4 for immunotherapies. The mean OS gain was substantially larger for most immunotherapy trials, due to relatively long survival. Median and mean OS gains did not differ for targeted therapies. Our findings imply a potential discrepancy between the estimates of effectiveness and cost-effectiveness of cancer treatments.