The KEYNOTE-0421,2 trial showed the benefit of treating patients with non-oncogene addicted advanced NSCLC with PD-L1 tumor proportion score over 50% with pembrolizumab as monotherapy over platinum-doublet chemotherapy. To contextualize these results, we undertake a detailed emulation of the inclusion criteria in KEYNOTE-042 using Norwegian health registry data and discuss both the clinical contexts, as well as the general utility of such registry data for pharmacoepidemiologic research in oncology. Within the population of patients with PD-L1 tumor proportion score over 50%, an observational analog of an intention-to-treat analysis showed similar results to those of the KEYNOTE-042 study.
© 2025 NordicRWE and The Author(s). Clinical Pharmacology & Therapeutics published by Wiley Periodicals LLC on behalf of American Society for Clinical Pharmacology and Therapeutics.