[Molecular response with triple therapy in patients with chronic myeloid leukemia].

BACKGROUND: Chronic myeloid leukemia is a myeloproliferative disorder which results from the translocation t(9;22)(q34;q11). Imatinib mesylate is an inhibitor of kinase tyrosine that has proved to be useful in patients with chronic myeloid leukemia. Our aim was to evaluate the major molecular response to 12 months with triple therapy, analyze the evolution of these patients, and the hematological and non-hematological toxicity.

METHODS: It was performed a longitudinal study in patients with diagnosis of chronic myeloid leukemia who were treated with sequential triple therapy: Pegylated interferon alpha 2a (90 μg/week for four weeks) + imatinib (800 mg a day for 30 days) + cytarabine (20 mg/m2 from day 1 to 10). Molecular and hematologic responses at 12 months of treatment were analyzed.

RESULTS: Thirty eight patients with chronic myeloid leukemia were eligible; the mean age was 43.4 years and the medians of hemoglobin levels, leukocyte and platelet counts at diagnosis were 10 g/dL (5.1 to 16.0 g/dL), 208 000/μL3 (10 600 to 529 000/μL3) and 573 500/μL3 (130 000 to 4 272 000/μL3), respectively. According to the Sokal score, 68.4 % had low risk, 26.3 % intermediate and 5.3 % high risk.

CONCLUSIONS: The hematologic response was similar to that reported in the IRIS study, but the molecular response was greater in more cases. The adverse hematological effects grades 3-4 and non-hematological were significative: 45 % and 87 %, which forces to continous monitoring. The combination of interferon alpha 2a, cytarabine and a high-dose of imatinib induced the major molecular response, of 68.4 %, at 12 months.