Temozolomide in combination with irinotecan for treatment of recurrent malignant glioma

The prognosis for patients with recurrent malignant glioma is poor. Both temozolomide and irinotecan have been shown to be active in this disease. A study was performed combining temozolomide 200 mg/m2 daily for 5 days and irinotecan 125 mg/m2 on days 6, 13, and 20 initially (Schedule A) and then changed to (Schedule B) temozolomide 200 mg/m2 daily for 5 days and irinotecan 350 mg/m2 on day 6. Each cycle was 28 days. All patients with recurrent tumor had to complete two cycles of therapy to be evaluable. Six cycles of treatment were provided for all responders. Thirty-two patients were treated, 6 with schedule A, 24 with schedule B, and 2 initially schedule A and then switched to schedule B. Eighteen patients (56%) had glioblastoma and 14 patients and anaplastic glioma (AOA 8, anaplastic astrocytoma 4, AO 2). Eighty-three percent (15/18) of patients with glioblastoma responded (complete response [CR] 2, partial response [PR] 3, stable disease [SD] 10). Median duration of response was 24 weeks, and 6-month progression-free survival (PFS) was 39% (7/18). Fourteen patients with anaplastic glioma were treated and all responded (CR 3, PR 2, SD 9). Median duration of response was 29 weeks and 6-month PFS was 71% (10/14). Grade IV leukopenia occurred in one patient and grade IV thrombocytopenia in two patients. Two patients were admitted to the hospital for neutropenic fever. Nonhematologic toxicity was mild and mostly gastrointestinal. These results demonstrate a favorable response and low toxicity with combined irinotecan and temozolomide therapy and warrant further clinical evaluation.