Cytosine arabinoside (NSC 63878) and daunorubicin (NSC 83142) therapy in acute nonlymphocytic leukemia

Earlier studies of cytosine arabinoside (Ara C) infusion for 5 days and dauborubicin (DNR) for 2 days suggested that longer treatment at the same doses could be tolerated. Infection acquisition in patients with acute myelocytic leukemia (AML) during remission induction prior to marrow recovery occurs at a constant rate. By intensifying the induction regimen and producing rapid bone marrow depression, a reduction in the patient's time at risk can be safely achieved. In this study, intravenous Ara C, 100 mg/m²/day continuously for 7 days and DNR, 45 mg/m²/day by rapid injection for 3 days was given to 8 previously untreated adult patients with AML. All 5 out of 8 less than 60 yr of age sustained complete remission. The 3 failures in the previously untreated group were elderly 67, 76, 78). Over one half of these patients were managed in an open ward and the remainder in laminar flow isolators. The period of hospitalization required to accomplish remission induction (a median of 35 days), was reduced compared to past experience with other regimens. One patient with previously untreated acute plasma cell leukemia remained in remission for a period of 21 mth. Five out of 8 patients from 26-60 yr of age, who had received prior treatment for their AML, achieved a remission. The combined remission rate for both previously treated and previously untreated AML patients was 63%. Using the schedule of daunorubicin and continuous cytosine arabinoside, remission was achieved in 65% of all of the patients with a substantial reduction in hospitalization time. This program rapidly produces aplastic bone marrows without excessive toxicity. This pilot study served as the basis for a further comparative evaluation.