A Randomized Phase II Trial With Bevacizumab, Irinotecan and Cerebral Radiotherapy Versus Bevacizumab, Temozolomide and Cerebral Radiotherapy as First Line Treatment for Patients With Glioblastoma Multiforme

Significant activity (radiographic response rates of approximately 60%) has recently been demonstrated in phase II studies in patients with relapsed GBM from the combined use of Irinotecan (CPT-11) and bevacizumab. The 6-month progression-free survival rate is 30% and median survival duration is 9 months. The current first line therapy of GBM patients following initial surgical resection/debulking is the concomitant use of cerebral radiotherapy and the orally available alkylating agent temozolomide, followed by temozolomide for 6 months post-radiotherapy.

Considering the significant activity of the combination of Bevacizumab + irinotecan in patients with recurrent GBM, and considering the activity of temozolomide in GBM, it is proposed that the combination of Bevacizumab + Temozolomide may also be an active regimen. Bevacizumab + Temozolomide display non-overlapping toxicity clinically and thus their combined use without significant dose-reductions seems rational.

The toxicity from the combined use of the two drugs prior to radiotherapy, as well as the toxicity when administered together with radiotherapy, is evaluated.

This study will try to identity whether Bevacizumab and Irinitecan or Bevacizumab and Temozolomide should be the experimental arm in future phase III comparison with standard care with concomitant Temozolomide and radiotherapy.