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When prepared for transplantation with busulfan (BU) 14 mg/kg and cyclophosphamide (CY) 120 to 160 mg/kg, patients with thalassemia in risk class 3, aged younger than 17 years, who receive transplants from HLA-identical donors, had a 30% incidence of transplant rejection with recurrence of thalassemia. This, relatively poor, outcome was ascribed to insufficient immune suppression or to inadequate eradication of the thalassemic marrow, or both. In an attempt to enhance both immune suppression and eradication of the thalassemic clones, hydroxyurea, azathioprine, and fludarabine were added to the BU and CY. This regimen, called protocol 26, was applied to 33 consecutive patients with class 3 thalassemia aged younger than 17 years and was well tolerated with 93% survival. The incidence of recurrent thalassemia after the transplantation decreased from 30% to 8%.

In thalassemia after successful bone marrow transplantation (BMT), iron overload remains an important cause of morbidity. After BMT, patients have normal erythropoiesis capable of producing a hyperplastic response to phlebotomy so that this procedure can be contemplated as a method of mobilizing iron from overloaded tissues. A phlebotomy program (6 mL/kg blood withdrawal at 14-day intervals) was proposed to 48 patients with prolonged follow-up (range, 2 to 7 years) after BMT. Seven patients were not submitted to the program (five because of refusal and two because of reversible side effects). The remaining 41 patients (mean age, 16 +/- 2.9 years) were treated for a mean period of 35 +/- 18 months. All were evaluated before and after 3 +/- 0.6 years of follow-up. Values are expressed as mean +/- standard deviation (SD) or as median with a range (25 to 75 percentile). Serum ferritin decreased from 2,587 (2,129 to 4,817) to 417 (210 to 982) microg/L (P < .0001), total transferrin increased from 2.34 +/- 0.37 to 2.7 +/- 0.58 g/L (P = .0001), transferrin saturation decreased from 90% +/- 14% to 50% +/- 29% (P < .0001). Liver iron concentration evaluated on liver biopsy specimens decreased from 20.8 (15.5 to 28.1) to 4.2 (1.6 to 14.6) mg/g dry weight (P < .0001). Aspartate transaminase decreased from 2.7 +/- 2 to 1.1 +/- 0.6 (P < .0001) and alanine transaminase from 5.2 +/- 3.4 to 1.7 +/- 1.2 (P < .0001) times the upper level of normality. The Knodell score for liver histological activity decreased from 6.9 +/- 3 to 4.9 +/- 2.8 (P < .0001). These data indicate that phlebotomy is safe, efficient, and widely applicable to ex-thalassemics after BMT.

Background: Thalassemia patients with heavy iron overload risk further increase of body iron stores after bone marrow transplantation (BMT) due to intensive red-cell transfusions in the post BMT course and to massive mobilization of iron deposits from marrow cells following the conditioning regimen. Nevertheless, iron chelation has not yet been used during the transplant period, mainly for concerns related to the toxicity and antiproliferative properties of the drug., Methods: Fifteen thalassemic patients received desferrioxamine (DFO) before and during BMT according to two different schedules (first: from day -9 to day +60, and second: from day -9 to day -2, then from day +28 to day +60) at a dose of 40 mg/kg/day as a 24-hour intravenous infusion., Results: The median time to neutrophil, platelet and erythrocyte recovery showed no difference between DFO-treated patients and the control group (18 days vs. 15, 16 vs. 18 and 22 vs. 23, respectively; p: N.S.). The incidence of acute GVHD was 23% in the DFO group and 13% in controls (p: N.S.). The median serum ferritin (SF) at 6 months after BMT was significantly lower in the DFO-treated patients (2081 versus 4187; p: 0.007) than in the control group. This difference continued to be evident, though not statistically significant, during longer follow-up., Conclusions: Intravenous DFO therapy during BMT does not seem to have affected the engraftment parameters or the incidence of infections or GVHD. No adverse effects were observed during the therapy. Therefore thalassemic patients with heavy iron overload can be candidates for a course of i.v. chelation during the transplant period. This therapy could also be followed by post-BMT iron removal (i.e. phlebotomies or desferrioxamine) to accelerate the clearance of body iron deposits.