2008 Background: Bevacizumab is a humanized VEGF monoclonal antibody with promising activity in recurrent glioblastomas, alone and in combination with irinotecan. Patients who progress on this regimen are frequently maintained on bevacizumab and the concurrent chemotherapeutic agent is changed. The benefit of this therapeutic strategy is unknown. Methods: We retrospectively reviewed the clinical features and radiologic studies of 44 patients with recurrent malignant glioma who progressed on a bevacizumab-containing regimen and were then treated with an alternate bevacizumab-containing regimen. All patients received bevacizumab 10 mg/kg IV every 2 weeks. As the initial bevacizumab-containing regimen, 37 patients received irinotecan, 4 bevacizumab alone, 1 temozolomide and 2 carboplatin. As a second bevacizumab-containing regimen, 32 patients received carboplatin, 6 irinotecan, 2 BCNU, 1 CCNU, 1 etoposide, 1 erlotinib/rapamycin and 1 erlotinib. There was no limit on the number of prior therapies. Clinical c...