Dr Cho on the Investigation of Niraparib/Bevacizumab in Platinum-Sensitive, Recurrent Ovarian Cancer

“It [was] unknown whether double maintenance therapy with niraparib and bevacizumab in [the NIRVANA-R] trial is beneficial in [patients with] platinum-sensitive ovarian cancer who were previously treated with a PARP inhibitor.”

Hyun Woong Cho, MD, PhD, a member of the Department of Obstetrics and Gynecology at Korea University College of Medicine, explained the rationale for investigating niraparib (Zejula) plus bevacizumab (Avastin) for the treatment of patients with platinum-sensitive, recurrent ovarian cancer.

PARP inhibitors are a standard maintenance therapy for patients with platinum-sensitive ovarian cancer or PARP inhibitor–naive, recurrent, platinum-sensitive ovarian cancer, Cho began. However, he noted that within 5 years, more than half of the patients experience a recurrence after being treated with a PARP inhibitor, and responses to chemotherapy following PARP inhibition significantly decrease.

The phase 3 OReO trial (NCT03106987) demonstrated that maintenance therapy consisting of rechallenge with the PARP inhibitor olaparib (Lynparza) significantly improved progression-free survival (PFS) vs placebo in patients with ovarian cancer who were previously treated with a PARP inhibitor and responding to chemotherapy, Cho added. Nevertheless, he explained that it is unknown whether double maintenance therapy of niraparib plus bevacizumab could be beneficial for patients with platinum-sensitive ovarian cancer who previously received PARP inhibitors, which was the rationale for the phase 2 NIRVANA-R trial (NCT047346655).

Data from a subgroup analysis from the phase 2 trial demonstrated that at a data cutoff of June 1, 2024, and a median follow-up of 11.8 months, the PFS rates at 6 and 12 months were 68% (95% CI, 55%-85%) and 46% (95% CI, 31%-68%), respectively. The median PFS was 11.5 months (95% CI, 7.9-not reached). Patients included on the trial (n = 44) were required to have non-mucinous histology, be treated with penultimate chemotherapy over 12 months before enrollment, and have a complete or partial remission on their most recent chemotherapy. Following enrollment, patients were treated with niraparib/bevacizumab as maintenance treatment until disease progression. Notably, the primary end point was the 6-month PFS rate, which was estimated to be 68%.