LBA1 Background: BEV, a humanized anti-VEGF monoclonal antibody, has demonstrated single-agent activity in patients with recurrent EOC, or PPC. The therapeutic impact of concurrent ± maintenance BEV with standard chemotherapy (CT) was evaluated in an international, double-blind, placebo-controlled phase III trial. METHODS Eligible patients had newly diagnosed, previously untreated EOC, PPC or FTC following abdominal surgery for staging and maximal effort at tumor debulking; stage III (macroscopic residual disease) or stage IV disease. The randomly allocated regimens were (1) CT (IV paclitaxel 175 mg/m2 + carboplatin AUC 6 cycles 1-6) + placebo cycles (C)2-22 (R1) (2) CT + concurrent BEV (15 mg/kg) C2-6 + placebo C7-22 (R2) (3) CT + concurrent BEV C2-6 + maintenance BEV C7-22 (R3) Infusions were administered d1 of a 21d cycle. The primary endpoint is progression-free survival (PFS) (radiographic, CA125, clinical criteria or death); secondary endpoints include overall survival, safety, and QoL. RESULTS 1,873 patients, median age 60, were enrolled from 9/05 - 6/09. Stage III optimally debulked (34%), stage III sub-optimally debulked (40%), and stage IV (26%) patients were similarly distributed in each treatment group. Grade 3 - 4 hypertension was reported in 1.6% (R1), 5.4% (R2), and 10.0% (R3). Grade ≥ 3 GI perforation, hemorrhage or fistula occurred in 0.8% (R1), 2.6% (R2) and 2.3% (R3). Relative to R1, the hazard of first progression or death for R2 was 0.908 (95% CI: 0.795 - 1.04, p=0.16) and for R3 was 0.717 (95% CI: 0.625 - 0.824, p<0.0001). CONCLUSIONS This study demonstrates that front-line treatment of EOC, PPC, and FTC patients with CT plus concurrent and maintenance BEV prolongs PFS. This is the first anti-angiogenic agent to demonstrate benefit in this population. [Table: see text].