Niraparib Maintenance Prolongs PFS in BRCA-Positive Ovarian Cancer

Darlene Dobkowski, MA

In patients with ovarian cancer and BRCA mutations who were enrolled in 3 different trials, maintenance treatment with niraparib improved progression-free survival compared with placebo with no new safety signals.

Pooled data from 3 late-phase clinical trials shows that maintenance therapy with niraparib (Zejula) significantly improved progression-free survival (PFS) in patients with BRCA-mutated ovarian cancer, according to results presented during the 2021 ASCO Annual Meeting.

“Patients with BRCA-mutated ovarian cancer derived a significant (PFS) benefit from niraparib maintenance treatment across all three trials in first-line and recurrent settings after response to platinum-based chemotherapy,” said Antonio Gonzalez Martin, MD, co-director of the department of medical oncology at Clinica Universidad de Navarra in Spain and president of the Spanish Ovarian Cancer Group (GEICO), during the poster presentation at the 2021 ASCO Annual Meeting.

Researchers assessed the efficacy and safety of niraparib compared with placebo in patients with BRCA mutated ovarian cancer from three trials: ENGOT-OV16/NOVA (n = 203), PRIMA/ENGOT-OV26/GOG-3012 (n = 223) and NORA (n = 100).

In particular, patients in the PRIMA trial had newly diagnosed advanced ovarian cancer and responded to first-line platinum-based chemotherapy. Patients in the ENGOT-OV16/NOVA and NORA trials had platinum-sensitive, recurrent ovarian cancer. All trials included a subgroup analysis by BRCA mutation status.

Of the 526 patients in all three trials, the most common mutation was in BRCA1, accounting for 60.6% to 80% of BRCA mutations.

Niraparib derived a significant PFS benefit compared with placebo in patients with BRCA mutations from the PRIMA (HR = 0.4; 95% CI, 0.27-0.62), NOVA (HR = 0.27; 95% CI, 0.17-0.41) and NORA trials (HR = 0.22; 95% CI, 0.12-0.39). No differences were observed in the PRIMA trial in patients with BRCA1 and BRCA2 mutations. For patients in the NOVA trial, HRs for PFS were 0.39 for those with BRCA1 mutations (95% CI, 0.23-0.66) and 0.12 for those with BRCA2 mutations (95% CI, 0.05-0.33).

Any-grade hematological treatment-emergent adverse events (TEAEs) occurred in at least 20% of patients assigned niraparib. This was also seen for TEAEs of any grade.

“The most common treatment-emergent adverse events of any grade were thrombocytopenia, anemia, neutropenia and nausea across all three trials,” Gonzalez Martin said during the presentation. “The most common grade 3 or 4 hematological treatment-emergent adverse events were thrombocytopenia, anemia and neutropenia.”

For nonhematological treatment-emergent adverse events, the most common of any grade included nausea, constipation and fatigue, all of which were mainly mild or low grade, Gonzalez Martin said.

“Importantly, no new safety signals were identified,” Gonzales Martin added.

Reference

Gonzalez Martin A, Matulonis UA, Korach J, et al. Niraparib efficacy and safety in patients with BRCA mutated (BRCAm) ovarian cancer: Results from three phase 3 niraparib trials. J Clin Oncol. 2021;39(suppl 15):Abstract 5518.