An open-label, multicenter, phase II study of bevacizumab for the treatment of angiosarcoma and epithelioid hemangioendotheliomas

Background: To determine efficacy and safety of bevacizumab, a recombinant humanized antibody against vascular endothelial growth factor (VEGF), in the treatment of metastatic or locally advanced angiosarcoma and epithelioid hemangioendotheliomas. Patients and methods: In this single-arm phase II trial, 32 patients were enrolled and they received bevacizumab 15 mg/kg IV infusion in 21-day cycles. Patients had disease that was deemed not surgically resectable, Eastern Cooperative Oncology Group (ECOG) performance status of <1, adequate organ function and had not received any radiation treatment in the last 28 days. Results: Of the 30 patients evaluated for efficacy and toxic effect, four (two angiosarcoma and two epithelioid hemangioendothelioma; 17%) had a partial response. Fifteen patients (11 angiosarcoma and 4 epithelioid hemangioendothelioma; 50%) showed stable disease with a mean time to progression of 26 weeks. Bevacizumab was well tolerated with only one grade 4 adverse event. Expected known toxic effects of the drug were manageable. Conclusion: Bevacizumab is an effective and well-tolerated treatment for metastatic or locally advanced angiosarcoma and epithelioid hemangioendotheliomas. Further phase III studies of bevacizumab in combination with other chemotherapeutic agents and/or radiation treatment are warranted.