PHASE-II STUDY OF TOPOTECAN IN PATIENTS WITH RECURRENT MALIGNANT GLIOMA

Background: The NCIC Clinical Trials Group has an ongoing interest in assessing investigational agents in minimally pretreated patients with malignant glioma. Topotecan is one of the first topoisomerase I inhib itors to enter clinical trials and has shown early evidence of activit y in several solid tumors. We have conducted a phase LI trial of topot ecan in patients with malignant glioma. Methods: Adults with malignant glioma and recurrent contrast enhancing measurable disease (greater t han or equal to 2 x 2 cm) were eligible. Topotecan 1.5 mg/m(2) i.v. wa s given daily x five days every three weeks. Response and toxic effect s 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 w ere assessable for response and toxicity. Two patients (6%) responded: one had a complete radiographic response, but died with neutropenic s epsis, and the second had a prolonged partial response (>97 weeks). Tw enty-one patients (68%) had stable disease for five to 86+ weeks (medi an 19) and eight (26%) had progressive disease after one cycle. Toxici ty was primarily hematologic; 18 (58%) had grade 4 neutropenia (<0.5 x 10(9)/1), usually brief, and three (10%) grade 4 thrombocytopenia (<2 5 x 10(9)/1). Twelve of 109 cycles (11%) were given at reduced dose. C onclusions: Topotecan in this dose and schedule has only modest activi ty in recurrent glioblastoma and anaplastic astrocytoma.