Clinical Protocol for a Phase II Study of Leridistim (SC-70935) in Adult Patients (Age>55) With Acute Myeloid Leukemia (AML) Receiving Chemotherapy With the Cytarabine and Daunorubicin "7+3" Regimen

OBJECTIVES: I. Determine the maximum tolerated dose or hematopoietically active dose of leridistim administered with induction chemotherapy in older patients with acute myeloid leukemia. II. Determine the effect of leridistim on the duration of grade IV neutropenia during the induction course in these patients. III. Determine the safety and tolerability of leridistim in these patients. IV. Compare the effect of leridistim vs filgrastim (G-CSF) on the duration of thrombocytopenia, the incidence of infection, and the need for IV antibiotics in these patients. V. Compare the effect of leridistim vs G-CSF on the number of days of platelet and/or red blood cell transfusions in these patients. OUTLINE: This is a dose escalation study of leridistim and then a randomized, open label, multicenter study. Patients are randomized to one of two treatment arms. All patients receive induction chemotherapy consisting of daunorubicin IV over 15-30 minutes on days 1-3 and cytarabine IV continuously on days 1-7. Patients who do not achieve aplasia after one induction course may receive a second course. Dose Escalation Phase: Patients receive leridistim subcutaneously (SQ) every other day beginning on day 11-14 and continuing for 42 days or until blood counts recover. Cohorts of 6 patients receive escalating doses of leridistim until the maximum tolerated dose (MTD) or hematopoietically active dose (HAD) has been determined. The MTD is defined as the dose prior to the dose level at which at least 2 of the same dose limiting toxicities occur in different patients. Consolidation Phase: Patients then receive consolidation chemotherapy consisting of cytarabine IV over 1 hour every 12 hours (patients 70 years and under) or every 24 hours (patients over 70 years) on days 1-6. Beginning 24-48 hours after completion of consolidation chemotherapy, patients receive leridistim as above. Randomized Phase: Eligible patients will receive induction and consolidation chemotherapy as outlined above. Then patients are randomized to one of two treatments. Arm I: Patients receive leridistim SQ every other day for up to 42 days or until blood counts recover. Arm II: Patients receive filgrastim (G-CSF) SQ daily for up to 42 days or until blood counts recover. Patients are followed at day 30 and then at 6 and 12 months. PROJECTED ACCRUAL: A total of 86 patients (36 for phase I and 50 for phase II) will be accrued for this study.