Phase II trial of 7 days on/7 days off temozolmide for recurrent high-grade glioma

Background. A phase II trial was performed to evaluate the efficacy of a dose-dense, 7 days on/7 days off schedule of temozolomide for patients with recurrent high-grade gliomas (HGG). Methods. Sixty patients with recurrent HGG received temozolomide at 150 mg/m(2)/day on days 1-7 and days 15-21 during each 4-week cycle. The primary endpoint was 6-month progression-free survival (PFS-6), with a secondary endpoint of overall survival (OS). A further exploratory objective included the investigation of whether methylation status of the O(6)-methylguanine-DNA methyltransferase (MGMT) promoter within tumor tissue predicted outcomes. Results. Among patients with glioblastoma (n = 40), PFS-6 was 10% (95% CI, 3%-24%) with median OS of 21.6 weeks (95% CI, 16.9-30.6 weeks). PFS-6 for grade III glioma patients (n = 20) was 50% (95% CI, 27%-73%), and median OS was 100.6 weeks (95% CI, 67 weeks to not reached). There were trends towards longer PFS and OS with MGMT promoter methylation (log-rank test; P = .06 for PFS; P = .07 for OS). Additionally, bevacizumab-naive glioblastoma patients had significantly longer PFS and OS (median PFS was 8.07 weeks [95% CI, 8 weeks to not reached] vs 7.57 weeks [95% CI, 7.29-8.29 weeks], log-rank test, P < .001; median OS was 62 weeks [26.1 weeks to not reached] vs 18.2 weeks [13.9-27.3 weeks], log-rank test, P < .001). Conclusions. The dose-dense temozolomide regimen was well tolerated, although it has no significant activity in this population.