Phase II study of aziridinylbenzoquinone (AZQ) in patients with central nervous system malignancies: a Southwest Oncology Group Study

AZQ, an alkylating agent with lipophilic characteristics allowing CNS penetration was studied in patients with primary CNS malignancies refractory to surgical and radiotherapeutic modalities. Responses were evaluated by three criteria: neurologic examination, performance status and CT scan of the brain. Improvement in all three parameters with stable or decreasing doses of decadron was required for a partial response. Thirty-six poor risk (prior chemotherapy) patients with Grades III and IV astrocytomas were treated with 30 mg/m2. Three patients had a partial response (14, 17, 60 weeks duration). Two patients had mixed responses (worsening of one disease parameter with improvement in another), four had stable disease and one patient had improvement in neurologic parameters with a stable CT scan. Twenty-six patients had increasing disease. Fifteen good risk patients (no prior chemotherapy) with recurrent grades III and IV astrocytomas were treated at a dose of 40 mg/m2 intravenously every three weeks. There were no objective responses in this group of patients. Three patients with nonastrocytomas were treated and no responses observed. The drug was well tolerated. Myelosuppression in the form of leukopenia and thrombocytopenia was the major toxicity. Myelosuppression required dose reductions in eight patients and discontinuation of therapy due to repeated treatment delays in two patients. AZQ at doses of 30 and 40 mg/m2 given on an intermittent bolus schedule is inactive in patients with Grades III and IV recurrent astrocytoma.