Tacrolimus (FK506) and methotrexate as prophylaxis for acute graft-versus-host disease in pediatric allogeneic stem cell transplantation

Currently, limited data exist on the role of tacrolimus (FK506) in pediatri c allogeneic marrow transplantation. Forty-one patients who received tacrol imus as prophylaxis were reviewed, with a median age of 9 years (range 0.2- 16 years). Twenty-one patients underwent related donor transplants and 20 u nderwent unrelated donor transplants. All patients received tacrolimus begi nning the day Drier to transplant at a dose of 0.03 mg/kg/day by continuous i.v. infusion, When clinically possible, patients were switched to oral th erapy in two divided doses, at four times the intravenous dose, Tacrolimus levels were monitored twice a week, and dosages adjusted to maintain serum levels 5-15 ng/ml, Common adverse effects included hypomagnesemia (98 %), h ypertension (49%), nephrotoxicity (34%), and tremors (32 %), Less common si de-effects (<10% cases) included seizures and hyperglycemia. The median tim e to ANC recovery (ANC >500 x 10(6)/l) was 15 days, For the related donor g roup, the incidence of grade II-IV acute GVHD was 33%, and grade III-IV GVH D 19%. For the unrelated donor group, the incidence of grade II-IV acute GV HD was 55%, and grade III-IV GVHD 30%. Overall, tacrolimus therapy was well tolerated as prophylaxis for acute? GVHD in pediatric patients undergoing allogeneic transplantation.