Twenty-eight adult patients with nonirradiated malignant gliomas of the brain were administered a combination of methyl-CCNU (130 mg/m2, p.o., day 1), vincristine (2 mg/m2, i.v., day 1) and procarbazine (100 mg/m2, p.o., days 2 to 15) (MVP), scheduled to be given at successive 6 week intervals. Nineteen (67.9%) were not responsive to MVP and 9 (32.1%) were. Of 16 who had previous partial resection of their tumors, 8 (50%) responded to MVP and 8 (50%) did not. Of 12 who had previous biopsy, only 1 (8.3%) responded. Overall 1-year survival rate for the 28 patients was 28.6%. Major side effects of MVP were leukopenia, thrombocytopenia, pulmonary emboli, and thrombophlebitis, detected mainly during the first 20 to 24 weeks of treatment.