Comparison of survival outcomes between olaparib and niraparib maintenance therapy in BRCA-mutated, newly diagnosed advanced ovarian cancer

Introduction. This multicenter retrospective cohort study aimed to compare survival outcomes and adverse events between maintenance therapy with two poly (ADP-ribose) polymerase (PARP) inhibitors, olaparib and niraparib, in patients with BRCA-mutated, newly diagnosed advanced epithelial ovarian cancer (EOC) who responded to platinum-based chemotherapy.Methods. We enrolled stage III-IV EOC patients with germline and/or somatic BRCA1/2 mutations that had received maintenance therapy with olaparib or niraparib. A 3:1 propensity score matching was conducted using two variables: residual disease size and the presence of germline variants. The primary outcome was progression-free survival (PFS), and the secondary outcomes were time to first subsequent therapy (TFST), over-all survival (OS), and treatment-emergent adverse events (TEAEs).Results. In the propensity score-matched analysis, 80 patients who received olaparib and 31 patients who received niraparib were matched (3:1). In the propensity score-matched cohort, median PFS with olaparib vs. niraparib was not reached vs 31.5 months (HR, 1.08; 95% CI, 0.47-2.52; p = 0.854). The median TFST was not reached vs 31.8 months (HR, 1.20; 95% CI, 0.51-2.81; p = 0.682), and neither olaparib nor niraparib reached the median OS (HR, 0.42; 95% CI, 0.01-17.61; p = 0.649). In terms of the incidence rates of any-grade hemato-logic or non-hematologic TEAEs, higher rates of thrombocytopenia (p = 0.021) and neutropenia (p = 0.011) were observed in the niraparib group.Conclusion. Advanced EOC patients with BRCA1/2 mutations exhibited no significant difference in OS between olaparib and niraparib, indicating the need to consider individualized strategies for selecting PARP inhibitors based on adverse event profiles.(c) 2023 Elsevier Inc. All rights reserved.