Sorafenib and bevacizumab combination targeted therapy in advanced neuroendocrine tumour: A phase II study of Spanish Neuroendocrine Tumour Group (GETNE0801)

BackgroundSorafenib and bevacizumab as single agents have shown efficacy and acceptable toxicity in NETs phase II trials. Sorafenib and bevacizumab combination has shown manageable toxicity in phase I trials in solid tumours. The purpose of this study was to evaluate the safety and efficacy of the combination of sorafenib and bevacizumab in patients with advanced neuroendocrine tumours.MethodsOpen-label, uncontrolled, multicenter, phase II clinical trial. Eligibility criteria: age ? 18 years, histologically confirmed measurable advanced NETs; 1 prior chemotherapy allowed; ECOG-PS 0–2. Patients were treated during 6 months and followed up for an additional 6 months. Treatment: sorafenib 200 mg bid (days 1–5 of each week) and bevacizumab 5 mg/kg once every 2 weeks (day 1, week 1). Tumour response was performed according to RECIST (v1.0) every 2 months during the treatment period. Adverse events were graded according to CTCAE (v3.0).Findings44 Patients enrolled, 59.1% men, median age 60 years (range 32–76). 70.5% carcinoid tumours, 29.5% pancreatic tumour. Baseline target lesions mainly in the liver (86.4%). Global PFSR was 90.9% (91.7% carcinoid tumours and 88.9% pancreatic tumours). Median PFS was 12.4 months, median TTP was 14.5 months, ORR was 9.4% and DCR was 95.1%. Most common grade 3–4 toxicities: asthenia (11.4%) and hand–foot skin reaction (15.9%).InterpretationSorafenib and bevacizumab combination showed clinical benefit but unfavourable safety results compared with drugs in monotherapy. Further development of this combination is not warranted and a sequential approach is recommended instead.