Fludarabine-based protocol for human umbilical cord blood transplantation in children with fanconi anemia

Purpose: A novel conditioning regimen of fludarabine monophosphate (FLM), anti-T-lymphocyte globulin (ATG), and low-dose cyclophosphamide with no irradiation for human umbilical cord blood transplantation (HUCBT) for the treatment of Fanconi anemia (FA) is described. Patient and Methods: A 12- year-old girl with FA received a human umbilical cord blood transplant from a fully matched sibling donor. After the HUCBT, the patient was given granulocyte colony stimulating factor in combination with erythropoietin. Pretransplant conditioning consisted of FLM (30 mg/m²/d) from day -10 to day -5, cyclophosphamide (10 mg/kg/d) on day -7 and -6, and rabbit ATG (ATG- Frasenius, 10 mg/kg/d) from day -4 to day -1. Cyclosporin A (3 mg/kg/d) was administered from day -1 as graft-versus-host disease prophylaxis. Cord blood from a sibling donor was used as a source of hematopoietic stem cells. Results: Engraftment was normal and sustained. The regimen was well tolerated with very mild toxicity and no major transplant-related complications or >grade II graft-versus-host disease. Chimerism was 100% donor origin as determined by restriction fragment length polymorphism. Conclusions: It is possible to achieve sustained engraftment and only mild toxicity in FA after HUCBT with a conditioning regimen of FLM, ATG, and cyclophosphamide with no irradiation. These preliminary results with this novel conditioning protocol are encouraging and should be evaluated in a larger group of patients with FA undergoing HUCBT.