Interferon Alpha 2A in the Treatment of Chronic Myelogenous Leukemia in Chronic Phase. Results of the Spanish Group

Abstract

Fifty-one patients with CML in chronic phase, less than two years after diagnosis, were included in one multicentric study aiming to assess the therapeutic value of interferon alpha 2a (IFN alpha 2a) in this setting. The therapeutic scheme was biphasic: The patients were first treated with hydroxyurea, and afterwards only received IFN alpha 2a, at a planned dose of 5MU/m2/day, s.c. Thirty-eight patients (81%) achieved an hematologic response, which was complete in 57% of the total group. The median time to response was of 42 days. In the last evaluation, a complete hematologic response was sustained in 21 patients (47%). Philadelphia suppression was obtained in 44% of the patients who achieved hematologic responses; major cytogenetic responses were obtained in 16% of the patients. The patients who obtained genetic responses were significantly younger and had a shorter interval from diagnosis to IFN than the patients who did not respond. At the moment of evaluation, 90% of the patients are alive, but the median follow-up of the series (217 days, range 21-1150) is too short to analyze any impact of IFN over survival. Six patients (12%) discontinued IFN because of toxicity, three of them because of severe flu-like syndrome. Leukopenia and thrombocytopenia were frequent, but rarely severe. Hypertriglyceridemia has been a very frequent finding.