Purpose: The aim of this randomized, phase II trial was to explore the activity and safety of adding bevacizumab to paclitaxel once per week in treatment of angiosarcomas (AS).
Methods: Patients were treated with paclitaxel alone (90 mg/m(2) per week for six cycles of 28 days each; arm A) or with paclitaxel combined with bevacizumab (10 mg/kg once every 2 weeks; arm B). In the combination treatment arm, bevacizumab was administered after the six cycles of chemotherapy as maintenance therapy (15 mg/kg once every 3 weeks) until intolerance or progression occurred. Stratification factors were superficial versus visceral AS and de novo versus radiation-induced AS. The primary end point was the 6-month progression-free survival (PFS) rate, which was based on RECIST, version 1.1. Statistical assumptions were P0 = 20%, P1 = 40%, a = 10%, and b = 20%. P0 was the PFS rate at 6 months defining inactive drug, and P1 was the PFS rate at 6 months defining promising drug.
Results: A total of 52 patients were enrolled, and 50 were randomly assigned in 14 centers. The most common primary sites were the breast (49%) and skin (12%). There were 17 (34%) visceral and 24 (49%) radiation-induced AS. The performance status was 0 in 24 patients (49%) and 1 in the remaining 25 patients (51%). The median follow-up time was 14.5 months. Both treatment regimens were considered active, with 6-month PFS rates of 54% (14 of 26) in arm A and 57% (14 of 24) in arm B. The median overall survival rates were 19.5 months in arm A and 15.9 months in arm B. Toxicity was higher with the combination arm and included one fatal drug-related toxicity (intestinal occlusion).
Conclusion: The primary objective was met in both treatment arms. However, the present data do not support additional clinical investigation of combined paclitaxel/bevacizumab for the treatment of advanced AS.
© 2015 by American Society of Clinical Oncology.