Introduction Targeted therapy has become the mainstay maintenance treatment for patients with advanced ovarian cancer, including those with BRCA1 or BRCA2 mutations. Poly ADP ribose polymerase (PARP) inhibitors, including Niraparib and Olaparib, have demonstrated effectiveness in treating patients in complete or partial remission. However, there is a lack of research comparing the survival outcomes between these two agents. We aimed to compare the survival outcomes associated with niraparib and olaparib in patients with advanced ovarian cancer.

Methods We conducted a single institution, retrospective study on patients with stage III and IV ovarian cancer who had received either Niraparib or Olaparib from November 2019 to February 2023. Patients were stratified according to which PARP inhibitor they received. Our primary objective was to assess the progression-free survival (PFS) and overall survival (OS).

Results A total of 104 patients received a PARP inhibitor during the study timeframe. Thirty-four (32.7%) of patients received niraparib and 70 (67.3%) of patients received olaparib. Median age of patients was 56.8±7.5 years in niraparib group and 57.2±8.8 years in olaparib group. Median PFS was 31.8 months (28.8–34.9) for the olaparib group and 24.8 months (23.095–26.409) for the niraparib group (p=0.247). The median OS was 36.5 months (34.638–38.459) for olaparib group and 25.5 months (24.448–26.476) for the niraparib group (p=0.599), with no significant difference.

Conclusion/Implications This study compared the survival outcomes of two most commonly prescribed PARP inhibitors. Our results show that olaparib and niraparib were comparable in terms of survival outcome in patients with advanced ovarian cancer.