Objectives: To evaluate the effectiveness and safety of pembrolizumab use in advanced melanoma in a real-life context; and to explore the existence of an efficacy-effectiveness gap, comparing registry data with the reference clinical trial.
Methods: This study followed the guidelines for good pharmacoepidemology practice. An ambispective cohort was constituted, initiating the observation upon drug approval (17/07/2015) and following exposed patients until death or cut-off date (15/11/2019). The primary outcome was overall survival (OS); secondary outcomes comprised progression-free survival (PFS), overall response rate (ORR) and the occurrence of adverse events (AE). For all survival analyses, the Kaplan-Meier estimator was used, considering a 95% confidence interval (CI), aside with one-year survival rates.
Results: A total of 125 patients constituted the cohort, originating from 16 hospitals in Portugal. Median OS was estimated to be 16.9 months (CI95% 11.3-25.5) and the probability of survival after 1 year was 57.5% (CI95% 48.4%-65.6%). Median PFS was estimated to be 4.8 months (CI95% 3.9-6.7) and the probability of remaining progression-free after 1 year was 32.8% (CI95% 24.8-41.1). ORR was 30.4% (CI95% 22.5%-39.3%). AEs were experienced by 82% of patients, and 27% experienced AE≥ grade 3.
Conclusions: Our data suggest lower effectiveness in a real-life context than the efficacy reported in the clinical trial. Safety data seems, however, quite comparable to KEYNOTE-006.
Keywords: Portugal; antineoplastic agents, immunological; cancer registries; melanoma; pharmacoepidemiology; product surveillance, post marketing; treatment outcome.
© 2020 John Wiley & Sons Ltd.