Phase II study of topotecan in patients with recurrent malignant glioma. National Clinical Institute of Canada Clinical Trials Group

Abstract

Background: The NCIC Clinical Trial Group has an ongoing interest in assessing investigational agents in minimally pretreated patients with malignant glioma. Topotecan is one of the first topoisomerase I inhibitors to enter clinical trials and has shown early evidence of activity in several solid tumors. We have conducted a phase II trial of topotecan in patients with malignant glioma.

Methods: Adults with malignant glioma and recurrent contrast enhancing measurable disease (> or = 2 x 2 cm) were eligible. Topotecan 1.5 mg/m2 i.v. was given daily x five days every three weeks. Response and toxic effects were assessed at the end of each cycle.

Results: Thirty-one patients were entered onto the study: fifteen had glioblastoma, 16 anaplastic astrocytoma, all had prior radiation, 15 prior chemotherapy, and all were assessable for response and toxicity. Two patients (6%) responded: one had a complete radiographic response, but died with neutropenic sepsis, and the second had a prolonged partial response (> 97 weeks). Twenty-one patients (68%) had stable disease for five to 86 + weeks (median 19) and eight (26%) had progressive disease after one cycle. Toxicity was primarily hematologic; 18 (58%) had grade 4 neutropenia (< 0.5 x 10(9)/1), usually brief, and three (10%) grade 4 thrombocytopenia (< 25 x 10(9)/1). Twelve of 109 cycles (11%) were given at reduced dose.

Conclusions: Topotecan in this dose and schedule has only modest activity in recurrent glioblastoma and anaplastic astrocytoma.