Background: The efficacy of temozolomide has been evaluated in phase I and phase II trials in patients with recurrent malignant gliomas in the United States and the European Union. We report a feasibility study of the palliative efficacy of temozolomide for patients with recurrent anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM).
Methods: Sixteen patients with at least two prior chemotherapy regimens were enrolled in the study. Nine patients were confirmed to have GBM and 7 patients were confirmed to have AA at the latest pathology review, and all had a Karnofsky performance status (KPS) of over 50%. The median age was 57 years (range, 31-65 years).
Results: No cumulative toxicity was observed at any dose level when temozolomide was administered on a once-daily, 5-day schedule. Myelosuppression occurred, with the nadir being mid-late in the cycle (day 14 or 21). National Cancer Institute common toxicity criteria (NCI-CTC) grade 3 or 4 hematological toxicity did not occur. In the 9 GBM patients, the overall response rate (complete response + partial response [CR + PR]) was 0%. The median time to progression (TTP) was 3.5 months, and the rates of progression-free survival (PFS) at 6 and 12 months were 40% and 0%. In the 7 AA patients, the overall response rate (CR + PR) was 29% and median TTP was 9 months, while PFS rates at 6 and 12 months were 80% and 30%.
Conclusion: The favorable safety profile and the efficacy of temozolomide in Japanese patients are not incompatible with the results seen with patients in the United States and the European Union.