SUSTAINED INCREASE IN HEMOGLOBIN AND RBC FOLLOWING LONG-TERM ADMINISTRATION OF RECOMBINANT-HUMAN-ERYTHROPOIETIN TO PATIENTS WITH HOMOZYGOUSBETA-THALASSEMIA

Recombinant human erythropoietin (rHuEPO) was given subcutaneously thr ee times per week in an escalating dose from 500 u/kg to 950 u/kg toge ther with ferrous fumarate 305mg and folic acid 5mg/d, to 10 patients from four unrelated Arab families with homozygous beta-thalassaemia. S ix splenectomized patients showed a mean (+/-standard error) increase in haemoglobin from 7.1+/-0.1 to 9.3+/-0.1 g/dl (P = 0.0001), in RBC f rom 4.0 to 5.0 x 10(12)/l (P = 0.0001) and in nucleated RBC from 32+/- 7 x 10(10)/l to 82+/-6 x 10(10)/l while receiving 750 u/kg three times per week which persisted for 4-11 months, In two patients there was n o need for further blood transfusions, In three out of four unsplenect omized patients there were no changes in Hb and RBC despite dose escal ation, There were no significant changes in MVC, MCH and reticulocyte count, serum bilirubin, LDH, malonyldialdehyde (MDA) and vitamin E lev els. After 13 weeks of rHuEPO there was a mean increase in the percent age of F cells from 31+/-10% to 86+/-16% (P < 0.003) in three splenect omized patients and in one unsplenectomized patient from 56.4% to 80% without changes in the levels of Hb F. Globin chain synthesis ratios d id not change in four responding patients. Mean serum iron and transfe rrin saturation index did not change, whereas mean serum ferritin incr eased from 299+/-45 mu g/l to 480+/-20 mu g/l (P < 0.001). In seven re sponding patients an accelerated linear growth was indicated by positi ve changes in height standard deviation score for chronological age, S ide-effects were minimal throughout the treatment period.