Abstracts of the 12th International Charité Mayo Conference on “Global Perspectives and Future Directions in Women’s Cancer”

Background/Aim: Primary results from the ENGOT-OV16/NOVA study showed that niraparib maintenance therapy significantly prolonged progression-free survival in patients with platinum-sensitive recurrent ovarian cancer (PSROC) regardless of germline BRCA DNA repairassociated gene mutation (gBRCAm) or homologous recombination deficiency (HRD) biomarker status.Here we report updated final overall survival (OS) and long-term safety results.Patients and Methods: NOVA was a randomized, double-blind, placebo-controlled, phase 3 trial.Patients with PSROC were enrolled into independent gBRCAm and non-gBRCAm cohorts.Patients were randomized 2:1 to 300 mg niraparib or placebo once daily.Missing survival data for 92 patients were retrieved for the updated analysis (data cutoff: March 31, 2021).Final OS was evaluated in both cohorts and by non-gBRCAm HRD status.Results: A total of 553 patients were randomized.Median follow-up at data cutoff was >75 months across both cohorts.Survival status was available for 97.6% of patients.Overall OS maturity was 77.9%.Median OS for patients treated with niraparib vs. placebo was 40.9 vs. 38.1 months (hazard ratio=0.85;95% CI=0.61-1.20)for the gBRCAm cohort and 31.0 vs. 34.8months (hazard ratio=1.06;95% CI=0.81-1.37)for the non-gBRCAm cohort.For the non-gBRCAm cohort, median OS for patients treated with niraparib vs. placebo by HRD status was 35.6 vs. 41.4 months (hazard ratio=1.29,95% CI=0.85-1.95) for patients with HRD, 27.9 months for both (hazard ratio=0.93,95% CI=0.61-1.41)for homologous recombination-proficient patients, and 29.8 vs. 20.2months (hazard ratio=0.62,95% CI=0.29-1.36)for patients with unknown HRD status.No new safety signals were detected.Myelodysplastic syndromes/acute myeloid leukemia incidence rates for niraparib vs. placebo were 7.4% vs. 3.1% in the gBRCAm and 1.7% vs. 0.9% in the non-gBRCAm cohorts.Conclusion: 3363