Evaluation of Tolerability of Niraparib in Older Patients with Ovarian Cancer

Niraparib is a poly ADP-ribose polymerase inhibitor used to treat ovarian cancer. In this study, we examined the incidence of adverse effects of niraparib in patients aged 75 years and older to clarify the tolerability of niraparib in elderly patients. The study included patients with ovarian cancer who received niraparib at Ogaki Municipal Hospital between January 2020 and March 2024. The patients were divided into two groups: OG (n = 7) and YG (n = 20). Adverse events, relative dose intensity (RDI), incidence of adverse events in patients with renal impairment, and reasons for treatment discontinuation were compared using retrospectively collected medical records. Regarding the reasons for discontinuation, progressive disease (PD) was more common in the YG group (nine patients) than in the OG group (one patient) (P = 0.036). The median RDI (range) was 59.9％ (50 – 100) in the OG group and 56.9％ (16.3 – 100) in the YG group (P = 0.904). Grade 3 or higher thrombocytopenia occurred in four patients (14.8％) with a stage 3b or higher chronic kidney disease (CKD) severity and in one patient (3.7％) with a stage 3b or lower CKD severity (P = 0.017). In conclusion, older patients (>75 years of age) were less likely to tolerate niraparib than younger patients.