Phase I study of pyrazofurin and 5-azacytidine in refractory adult acute leukemia.

: Twenty-eight patients with refractory adult acute leukemia were treated with pyrazofurin and 5-azacytidine. Seven patients showed a response. Dermatitis and mucositis were severe at doses of pyrazofurin greater than 50 mg/m2/day and precluded administration of multiple courses in most patients. As a result of this toxicity, 16 patients received only one course of chemotherapy. The response rates achieved with this combination were not superior to those achieved with 5-azacytidine alone.