Incorporation of bevacizumab in the treatment of recurrent and metastatic cervical cancer: A phase III randomized trial of the Gynecologic Oncology Group.

Abstract

3 Background: Vascular endothelial growth factor (VEGF) promotes angiogenesis, a mediator of disease progression in cervical cancer. Bevacizumab (B), a humanized anti-VEGF monoclonal antibody, has shown single-agent activity in pretreated recurrent disease. We aimed to evaluate B in chemotherapy (CTX)-naive recurrent/persistent/metastatic cervical cancer. Methods: Using a 2x2 factorial design, patients were randomly assigned to CTX with or without B 15 mg/kg. The CTX regimens included cisplatin 50 mg/m2 plus paclitaxel 135-175 mg/m2 and topotecan 0.75 mg/m2 d1-3 plus paclitaxel 175 mg/m2d1. Cycles were repeated every 21 days until disease progression, unacceptable toxicity, or complete response. Overall survival (OS) was the primary endpoint with a reduction in the hazard of death by 30% using anti-VEGF therapy considered important (90% power, 1-sided alpha=2.5%). Final analysis was planned when 346 deaths were observed. Results: 452 patients were accrued from 4/6/09 to 1/3/12. The scheduled interim analysis occurred after 174 patients had died and showed that the topotecan-paclitaxel backbone was not superior to the cisplatin-paclitaxel backbone. A second interim analysis was conducted after 271 deaths. A total of 225 patients received CTX alone and 227 patients received CTX plus B. The randomized treatment groups were similar with regard to age, histology, performance status, previous platinum as a radiosensitizer, and recurrence, persistence, or advanced disease. The B-to-no-B hazard ratio (HR) of death was 0.71 (97.6% CI 0.54-0.95; 1-sided p=0.0035). Median survival was 17 m (CTX plus B) and 13.3 m (CTX alone). The RR were 48% (CTX plus B) and 36% (CTX alone) (p=0.0078). Treatment with B was associated with more grade 3-4 bleeding (5 vs 1%) thrombosis/embolism (9 vs 2%), and GI fistula (3 vs 0%). Conclusions: For the first time a targeted agent significantly improved OS in gynecologic cancer. The second interim analysis crossed the boundary for efficacy, warranting early release of this information. The nearly 4-month increase in median OS with the addition of B to CTX in women with recurrent cervical cancer is considered to be clinically significant. Clinical trial information: NCT00803062.