Progression‐free survival and overall survival in the first‐line treatment of BRCA wild‐type advanced epithelial ovarian cancer: An analysis of patient‐level data pooled from historical clinical trials

BACKGROUND: Progression-free survival (PFS) is a common primary endpoint in first-line epithelial ovarian cancer (EOC) trials; however, its relationship with overall survival (OS) remains uncertain. The patient-level PFS-OS association among individuals with BRCA wild-type advanced EOC treated with first-line platinum-based chemotherapy was evaluated. METHODS: This retrospective analysis pooled patient-level data from first-line advanced EOC historical trials sourced from the Medidata Enterprise Data Store. Eligible patients had BRCA wild-type disease and initiated platinum-based chemotherapy (index date) after primary debulking surgery or as neoadjuvant therapy before planned interval debulking surgery. The PFS-OS association was evaluated using Spearman's correlation (ρ) and landmark analyses at prespecified timepoints (9, 12, 15, and 18 months after index). RESULTS: Among 487 patients (50.1% aged ≥65 years; 90.1% White; 63.7% International Federation of Gynecology and Obstetrics stage III; 54.6% ECOG-PS 0; 37.3% primary debulking surgery; 53.0% interval debulking surgery; median follow-up 3.4 years), the median PFS and OS were 15.6 months (95% CI, 13.8-16.8) and 42.1 months (95% CI, 37.8-45.7), respectively. The PFS-OS correlation (ρ) was 0.7 (95% CI, 0.6-0.8). Across all landmarks, progression-free patients experienced longer subsequent OS; at 15 months, the unadjusted HR was 0.29 (95% CI, 0.22-0.37). Associations remained after covariate adjustment and did not vary by best overall response, bevacizumab use, or surgical type/outcomes. CONCLUSION: In this patient population, PFS demonstrated a consistently moderate, positive association with OS across multiple analytical approaches. These findings provide patient-level evidence that PFS is an informative early endpoint, although additional trial-level evaluations are needed to confirm PFS as a validated surrogate for OS in first-line EOC.