Bevacizumab and glioblastomas, a single-centre experience: how disease history and characteristics may affect clinical outcome.

Background: In 2009, bevacizumab, a monoclonal antibody to vascular endothelial growth factor, received accelerated approval by the United States Food and Drug Administration for the treatment of glioblastoma, based on its high response rate (RR) and 6-month progression-free survival (PFS-6). However, time to progression and overall survival (OS) were disappointing. Since 2008 have been data collected evaluating the safety and efficacy of bevacizumab in patients with relapsed malignant gliomas.

Patients And Methods: This is a retrospective review of adult patients with recurrent malignant gliomas treated with bevacizumab at a dose of 10 mg/kg every 14 days; some patients were also treated with irinotecan at a dose of 125 mg/m(2) every 14 days. Patients were evaluated for side-effects and clinical outcomes of response, progression and survival.

Results: Ten patients received bevacizumab and nine patients received the combination with irinotecan. Both single-agent bevacizumab and combination treatment were well-tolerated. RR was of 28% with no complete responses, PFS-6 was 20% and OS was 4.5 months (95% confidence interval: 3.07-5.98 months).

Conclusion: Although well-tolerated, the efficacy of bevacizumab was somewhat disappointing, possibly due to the high rate of secondary high-grade gliomas in the studied patient cohort and the late use of bevacizumab in the course of the disease.