Comparative Effectiveness of Bevacizumab and Olaparib Maintenance Therapy in Platinum-Sensitive Recurrent Ovarian Cancer: A Real-World Study with Exploratory Evaluation of Dose Reduction

Objective: To compare real-world PFS between BEV and OLA as maintenance therapy for PSROC, with an exploratory evaluation of clinical outcomes after OLA dose reduction. Methods: This retrospective multicenter study included 101 patients with first platinum-sensitive recurrent ovarian, fallopian tube, or primary peritoneal cancer who achieved a response to platinum-based chemotherapy and then received maintenance therapy. Patients were classified into three groups: BEV (n = 34), standard-dose OLA (n = 31), and dose-reduced OLA (n = 36). The primary endpoint was PFS; secondary endpoints were OS and adverse events. Survival outcomes were evaluated using Kaplan–Meier methods and Cox proportional hazards models. Results: In the primary comparison of all OLA-treated patients versus BEV, OLA was associated with longer PFS (HR 0.48, 95% CI 0.29–0.77), with median PFS of 19 months versus 16 months, respectively. OS did not differ significantly between groups (HR 0.60, 95% CI 0.34–1.05). In exploratory subgroup analyses, patients who underwent OLA dose reduction had numerically longer PFS than those who remained on the full dose; however, this comparison is vulnerable to time-dependent and selection biases and should be interpreted cautiously. Grade ≥ 3 hematologic toxicities were more frequent in the OLA groups but were clinically manageable. Conclusions: In real-world practice, OLA was associated with longer PFS than BEV in PSROC. Clinically necessary dose reduction appeared feasible without an obvious loss of benefit, although this finding requires cautious interpretation.