Marrow transplantation for thalassaemia following busulphan and cyclophosphamide.

30 patients with homozygous beta-thalassaemia aged 6 months to 7 years received allogeneic marrow transplants following busulphan (Bu) and cyclophosphamide (Cy). Post-transplant immunosuppression was with methotrexate (MTX) or MTX and Cy. The first 6 patients received 16 mg/kg Bu and 200 mg/kg Cy. 3 died of transplant-related complications and 3 survived without thalassaemia 701-762 days after transplantation. The subsequent 24 patients received 14 mg/kg Bu and 200 mg/kg Cy. 1 died on day 28 without engraftment and 23 survived 64-624 days after transplantation. 19 of the 23 surviving patients are without thalassaemia while 4 patients with initial engraftment became thalassaemic again in 32-46 days and survived 253-624 days after transplantation. The latest death was 50 days after transplantation. The probability of developing grade 2 or greater acute graft versus host disease (GVHD) in patients with sustained engraftment was 23%. 5 patients had chronic GVHD which is still active and causing disability in 3 patients 358, 456, and 477 days after transplantation. The actuarial survival was 86% and the actuarial disease-free survival was 73%.