Hematologic and clinical responses of thalassemia intermedia patients to hydroxyurea during 6 years of therapy in Iran.

Hydroxyurea (HU) is a well-known chemotherapeutic agent that has been used largely for the treatment of various myeloproliferative conditions over the past 20 years. In beta-thalassemia, the role for HU is much less clear and remains controversial. This study was undertaken to describe the hematologic and clinical responses of thalassemia intermedia patients to HU treatment during 6 years in Southern Iran. One hundred sixty-three thalassemia intermedia patients were selected among the 3,000 cases of beta-thalassemia in Southern Iran from 1998 to 2003. All patients underwent laboratory tests and quantitative hemoglobin electrophoresis. Group 1 comprised patients receiving regular blood transfusions (after age 2 years old). Group 2 comprised those without any history of blood transfusions suffering from chronic anemia or long-interval transfusions. The state of energy, fatigability, and mood were recorded before the trial. Facial change was compared before and after treatment with HU. Electrocardiogram and echocardiography were carried out before and during treatment with HU. All patients were treated with HU; the starting dose was 8 to 12 mg/kg/d given orally once a day. Of the 163 patients, 149 tolerated the HU well and showed a dramatic response to the drug. Eighty-three of 106 transfusion-dependent patients (group 1) became completely transfusion-free, and 23 had one or two transfusions throughout the study. Sixteen of 43 patients (group 2) who were on long-interval transfusions became transfusion-free and 27 group 2 patients were transfusion-free, with developing acceptable hemoglobin levels. After treatment, 97% of patients described an increase in exercise tolerance, and no significant facial change was observed after therapy. No change in spleen size was observed in 83% of the patients. HU therapy was also associated with a marked increase in hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin. HU may be administered in thalassemia intermedia patients to minimize or even obviate the need for regular transfusions and concomitant iron overload, and HU therapy appears to be safe and effective when administered in thalassemic patients.