Maintenance of PARP Inhibitor Rechallenge plus Bevacizumab in Patients with Platinum-Sensitive, Recurrent Ovarian Cancer Previously Treated with a PARP Inhibitor

PURPOSE: This study aimed to evaluate the efficacy and safety of PARP inhibitor (PARPi) rechallenge combined with bevacizumab as maintenance therapy in patients with platinum-sensitive recurrent ovarian cancer previously treated with a PARPi. PATIENTS AND METHODS: KGOG 3056/NIRVANA-R is a multicenter, single-arm, phase II trial that enrolled 44 patients with platinum-sensitive recurrent ovarian cancer who had received ≥2 prior lines of platinum-based chemotherapy and prior PARPi maintenance. Eligible patients achieving a response to the most recent platinum therapy received daily niraparib and triweekly bevacizumab until disease progression or unacceptable toxicity. The primary endpoint was the 6-month progression-free survival (PFS) rate, analyzed using a Simon two-stage design with adaptive statistical inference. RESULTS: The primary endpoint was met, with 26 of 44 patients (59.1%) remaining progression-free at 6 months. The estimated 6-month PFS rate was 68% [95% confidence interval (CI), 55%-85%], and the median PFS was 11.5 months (95% CI, 7.9-not reached). Subgroup analyses suggested greater benefit in patients with a longer treatment-free interval after the penultimate chemotherapy and in those who achieved a complete response to the most recent chemotherapy. Grade ≥3 treatment-related adverse events occurred in 27.3% of patients, with no treatment-related deaths or new safety signals observed. CONCLUSIONS: This is the first report of PARPi rechallenge with bevacizumab as maintenance therapy in this setting. The combination demonstrated promising efficacy, particularly in patients with favorable platinum responsiveness, and warrants further investigation in biomarker-driven studies. See related commentary by Sachdeva and Tan, p. 2525.