Phase II trial of bevacizumab with dose-dense paclitaxel as first-line treatment in patients with advanced ovarian cancer.

OBJECTIVES: To assess the tolerability and efficacy of bevacizumab with carboplatin and weekly paclitaxel as first-line adjuvant therapy for advanced stage ovarian cancer.

METHODS: After IRB approval, this single-institution, phase II study enrolled patients with stage III or IV epithelial ovarian cancer after primary cytoreductive surgery to treatment with carboplatin (AUC 5), weekly paclitaxel (80mg/m2), and bevacizumab (15mg/kg) every 3weeks for at least 6cycles. The primary endpoint was tolerability of at least 4cycles of therapy, with a target treatment success rate of >60%. Secondary endpoints included progression-free survival (PFS) and response rate. Plasma biomarkers were analyzed by the multiplex ELISA assays.

RESULTS: Thirty-three patients were enrolled with 30 evaluable patients receiving at least one cycle of combination treatment. Twenty-three patients (77%) were able to complete at least 4cycles of therapy per protocol, and the posterior probability that the treatment success rate is >60% is 0.77. Twenty-one patients (70%) were able to complete ≥6cycles of therapy. Median PFS was 22.4months for patients with optimal (R0) compared to 16.9months for optimal≤1cm (HR 1.71, 95% CI 0.58-4.98, p=0.33), and 16.9months for suboptimal>1cm (HR 3.75, 95% CI 1.05-13.34, p=0.04) disease. Increases in mean Flt-3L was significantly higher in responders versus non-responders (83.4 vs. 28pg/mL, p=0.05).

CONCLUSIONS: Adjuvant bevacizumab with dose-dense chemotherapy is associated with acceptable toxicity and a high likelihood of completing 4cycles of therapy. Dynamic changes in Flt-3L may represent a predictive marker to treatment response.