Sequential hydroxyurea-cytarabine chemotherapy for refractory non-Hodgkin's lymphoma.

Abstract
In experimental systems, hydroxyurea (HU) and cytarabine (ara-C) produce synergistic cytotoxicity to murine and human leukemia cells due to both cytokinetic and biochemical interactions that tend to enhance the effectiveness of ara-C. Therefore, we began a phase II trial of the combination of HU and ara-C to determine the efficacy and toxicity of this combination in treatment of patients with refractory non-Hodgkin's lymphoma. Chemotherapy began with HU 500 mg administered orally every six hours for four doses. Twelve hours following the fourth HU dose, ara-C 100 mg/m2/d was administered by continuous intravenous (IV) infusion for three days. Concomitantly with the three-day ara-C infusion, patients again received HU 500 mg orally every four hours. Cycles of therapy were repeated every 28 days. Twenty-five patients ranging in age from 26 to 70 years were enrolled in the study. Of 21 patients evaluable for response, nine (43%) obtained complete (CR) or partial remissions (PR). Most responding patients had ...