Combination therapy with interferon-alpha-2b and hydroxyurea in patients with chronic myelogenous leukemia

Abstract

Background: Interferon-α-2b (INF-α) has been able to achieve hematological and cytogenetic remission in chronic myelogenous leukemia (CML) patients and has a beneficial effect in patients who have relapsed after bone marrow transplantation (BMT). Hydroxyurea (HU) is the optimal conventional drug for treatment of CML in the chronic phase. IFN-α-based combinations have attempted to improve the results of single agent trials. Methods: Thirty previously untreated patients (16 males and 14 females, 26–70 years old), newly diagnosed as having CML (Philadelphia chromosome-positive) from a single hematology center, were treated with a combination of IFN-α and HU. The initial dose of IFN-α was 3×10 6 daily (not corrected for body surface). HU was administered at a dose of 40 mg/kg daily. The maintenance dosage was adjusted to the white blood cell (WBC) count. Results: The median observation time was 5.2 years. Twenty-seven patients maintained the prescribed dose of IFN-α, while three patients received IFN-α at a dose of 5×10 6 due to persistent elevated WBC count. Complete hematological remission was achieved in 20 patients (66.6%) and partial remission in the other 10 patients (33.3%). Two patients achieved complete cytogenetic remission and three patients partial cytogenetic remission. During the study period, 20 patients died (median survival 5.1 years). The youngest patient (26 years old) died during BMT. Ten patients are still alive (median survival 5.37 years). Side effects from IFN-α included fever (100%) and flu-like syndrome (80%); two patients had tumor cell lysis syndrome. Conclusions: Combination INF-α and HU therapy is well tolerated and effective for the treatment of CML patients, resulting in a rapid control of the disease with only minor side effects.