VM-26 and cytosine arabinoside combination chemotherapy for initial induction failures in childhood lymphocytic leukemia.

Combination chemotherapy with VM-26 and ara-C was given to 14 children with acute lymphocytic leukemia who had not responded to initial treatment with prednisone, vincristine, daunomycin, and asparaginase. Nine of these patients had also received ara-C. At diagnosis, five children were classified as having standard prognostic features and nine as being at high risk for treatment failure. The drug combination was administered by vein twice a week for four weeks at dosages of 165 mg/m2 for VM-26 and 300 mg/m2 for araC. Nine complete remissions, five in patients with high-risk leukemia, were induced with acceptable toxicity; all 9 subsequently were given continuation therapy with oral mercaptopurine and methotrexate. Four of the 9 patients have relapsed at 2--21 months. All treatment was stopped in 2 patients after 30 months of complete remission. Combinations of VM-26 and ara-C represent an alternative remission induction treatment for patients who fail to attain initial remission with agents of established effectiveness. These agents may especially benefit patients with prognostic features indicating a high risk of treatment failure.