Idarubicin and intermediate-dose cytarabine for myeloid blast crisis of chronic myelogenous leukemia--results of a phase-II trial.

Sixteen patients with Philadelphia chromosome-positive chronic myelogenous leukemia (CML) in myeloid blast crisis were treated with cytarabine (AraC) 600 mg/m2 two times daily for 5 days and idarubicin 12 mg/m2 for 3 days. Patients achieving a second chronic phase received interferon (IFN) alpha 2b 5 mio units/day daily and AraC 20 mg/day subcutaneously 14 days every month. Study end points were remission rate and survival. Four patients (25%) entered a second chronic phase and had a median survival of 31.1 weeks (range 16.1-111 weeks). Nine patients (56%) experienced blast crisis again and had a median survival of 12.9 weeks (range 5.1-59.3 weeks). Three patients (18.8%) died of septic complications during marrow aplasia. The median overall survival was 16.1 weeks (range 2.6-111 weeks) with no significant difference between responders and nonresponding patients. We conclude that AraC/idarubicin is as effective as other intensive regimens in inducing second chronic phase in patients with myeloid blast crisis of CML. Remission duration and survival are comparable to previous results. Further studies to improve survival are required.