Bevacizumab: in previously treated glioblastoma

Bevacizumab is a recombinant humanized monoclonal IgG(1) antibody that binds to human vascular endothelial growth factor and inhibits angiogenesis and hence tumour growth. It is available in the US and other countries for the treatment of several types of cancer, including glioblastoma that has recurred after previous treatment. Two prospective phase II trials have evaluated bevacizumab 10 mg/kg every 2 weeks for the treatment of previously treated glioblastoma. In the randomized, noncomparative, multicentre AVF3708g trial in patients with glioblastoma in first or second relapse, the rate of progression-free survival at 6 months was 42.6% and the objective response rate was 28.2% in recipients of bevacizumab alone (n = 85). In the bevacizumab plus irinotecan treatment arm (n = 82), the 6-month progression-free survival rate was 50.3% and the objective response rate was 37.8%. These rates were all significantly higher than historical control data. In the supporting, single-arm, single-centre, phase II NCI 06-C-0064E trial of bevacizumab in patients with glioblastoma that had recurred after radiotherapy and temozolomide chemotherapy (n = 48), the rate of progression-free survival at 6 months was 29% and the overall response rate based on Macdonald criteria was 35%. Given the nature of the disease, bevacizumab was generally well tolerated in these two phase II trials. In the AVF3708g trial, grade 3 or higher treatment-emergent adverse events occurred in 46.4% of bevacizumab and 65.8% of bevacizumab plus irinotecan recipients.