Overall survival (OS) in patients with platinum-sensitive relapsed ovarian cancer (PSROC) treated with olaparib maintenance monotherapy: Update from the L-MOCA trial.

Background: The open-label, single-arm, L-MOCA trial (NCT03534453) was the first study to demonstrate promising efficacy and tolerability of olaparib maintenance monotherapy in Asian patients with PSROC (median progression-free survival 16.1 months). Here we report the interim OS analysis. Methods: The study enrolled Asian patients with high-grade epithelial PSROC who had received ≥2 prior lines (L) of platinum-based chemotherapy and achieved complete or partial response. Patients were treated with oral olaparib (300 mg) twice daily until disease progression or unacceptable toxicity. A prespecified descriptive analysis of OS, a secondary endpoint, was conducted after approximately 3 years of follow-up. OS was analyzed in the full analysis set (FAS; defined as patients who received olaparib) and in subgroups defined by biomarker status (BRCAmutation/homologous recombination deficiency (HRD) status) and prior L of anticancer therapy. Results: By the date of data cutoff (16 Nov 2023), the median duration of follow-up was 40.0 months (range 0.5–64.2); 105 (46.9%) deaths occurred. In the FAS (N=224), the median OS was 54.4 months (95% CI 43.8–not evaluable [NE]). Median OS was not reached (NR; 51.9–NE) in the BRCA mutant (BRCA_m) subgroup and 44.3 months (34.8–59.1) in the BRCA wild-type (BRCA_wt) subgroup. In patients who had tumors with HRD, median OS was 59.1 (43.5–NE); among them, patients with HRD BRCA_wt showed a median OS of 54.6 months (33.0–NE); in the homologous recombination proficiency (HRP) subgroup, median OS was 37.2 months (28.3–56.1). Adverse events of any grade occurred in 222 (99.1%) patients. The incidence of myelodysplastic syndrome and acute myeloid leukemia remained low (3 [1.3%]). No new safety signals were identified. Conclusions: Olaparib showed promising OS benefit in Asian patients with PSROC, regardless of the BRCA mutation or HRD status, with a well-tolerated safety profile. Clinical trial information: NCT03534453. Research Sponsor: AstraZeneca.