Phase II randomized, double-blind, placebo-controlled study of AMG 386 (trebananib) in combination with cisplatin and capecitabine in patients with metastatic gastro-oesophageal cancer

Abstract

Background: We evaluated AMG 386, an investigational peptibody that neutralizes the interaction between angiopoietins-1 and -2 and the Tie2 receptor, combined with cisplatin/capecitabine (CX) as first-line treatment for metastatic gastro-oesophageal cancer. Patients and Methods: Patients with metastatic gastric, gastro-oesophageal junction, or distal oesophageal adenocarcinoma were randomized 1:1:1 to CX (cisplatin 80 mg/m2 IV Q3W; capecitabine 1000 mg/m2 P.O. BID for 14 days Q3W) plus intravenous AMG 386 10 mg/kg QW (Arm A) or 3 mg/kg QW (Arm B), or placebo QW (Arm C). The primary end point was estimated progression-free survival (PFS). Results: A total of 171 patients were enrolled. Median estimated PFS in Arms A, B, and C was 4.2, 4.9, and 5.2 months, respectively (hazard ratio for Arms A+B combined versus Arm C, 0.98; 95% CI 0.67–1.43; P = 0.92). Objective response rates were 27% (Arm A), 43% (Arm B), and 35% (Arm C). Incidence of grade ≥3 adverse events was 80% in Arm A, 84% in Arm B, and 75% in Arm C. There was no evidence of pharmacokinetic interactions. Conclusions: In this study, PFS and ORR were estimated to be similar with AMG 386 plus CX and placebo plus CX treatment. Compared with placebo, toxicity of AMG 386 plus CX was greater but manageable.