A Real World Perspective of PARP Inhibitor Use in Gynecological Cancer Patients

Abstract

Introduction Over the last few years, targeted therapy has become the mainstay maintenance treatment of patients with ovarian cancer including patients with BRCA1/BRCA2 mutations. Poly ADP ribose polymerase inhibitors (PARPi) are effective in the treatment of patients who are in complete or partial remission. PARPi are known to cause hematological adverse events (AEs), but have not been compared directly to each other. Objective Primary objective was to compare the incidence of hematological and non-hematological AEs associated with the use of PARPi. Methods This was a single institution, retrospective study evaluating patients who were treated with PARPi for ovarian cancer from January 2017 to October 2020. Patients were stratified according to which PARP inhibitor they received. Results Ninety-two patients were included in final analysis. Thirty-one (33.7%) patients received niraparib and 61 (66.3%) patients received olaparib. Median age of patients were 64.3 (range, 33.8 to 92.3) years, 66 (71.7%) were white, and 84 (91.3%) had an ECOG PS of 0/1. Patients in the niraparib group experienced a higher rate of hematologic AEs, with 11 (35.5%), 20 (64.5%), and 18 (58.1%) experiencing neutropenia, anemia, and thrombocytopenia, respectively. Eight (13.1%), 24 (39.3%), and 16 (26.2%) patients in the olaparib group experienced neutropenia, anemia, and thrombocytopenia, respectively. Conclusion This single institution retrospective study outlines the hematological toxicities observed between two PARPi. Our results suggested that niraparib tended to be associated with a higher risk for hematologic toxicities than olaparib. Anemia was the most common hematologic toxicity which was consistent with what has been widely documented in the literature.