Treatment with bevacizumab and irinotecan for recurrent high-grade glial tumors

Response rates to second-line chemotherapy in recurrent high-grade glial tumors are low and new effective treatments are needed. The objective of this study was to evaluate response rates and tolerability of chemotherapy with bevacizumab and irinotecan in recurrent high-grade gliomas.

Twenty patients with recurrent gliomas were treated with bevacizumab 5 mg/kg and irinotecan 125 mg/m(2) every 2 weeks. The response was evaluated by gadolinium-enhanced magnetic resonance imaging performed every 4 cycles of treatment.

The patients received 1 to 22 cycles of treatment. Nine of 19 patients available for response evaluation (47.3%) showed an objective radiologic response: 2 patients (10.5%) a complete response (CR), and 7 patients (36.8%) a partial response (PR). Two additional patients showed stable disease (SD) for 2 and 6 months, respectively. Eight patients developed rapid progression after 1 to 4 cycles of treatment. Median time to progression on treatment was 4.7 months. The 6-month progression-free survival (PFS) and overall survival (OS) were 25% and 55%, respectively. The adverse effects were mild and in all but 2 cases were no more than grade 2. There were no thrombotic complications or significant bleeding other than epistaxis.

The preliminary data show a promising high response rate of recurrent high-grade gliomas to chemotherapy with bevacizumab and irinotecan. The regimen is associated with minimal toxicity.