Program: Oral and Poster Abstracts
Session: 112. Thalassemia and Globin Gene Regulation: Poster II
All patients engrafted and achieved evidence of donor haemopoiesis on day +28 and achieved transfusion-independence and donor haematological values. No patient suffered primary or secondary graft failure. There was one death, one on day +257 due to idiopathic pneumonia syndrome in a patient with b thalassaemia major. Acute GvHD ≥ grade 2 occurred in 5 patients (41.7%). Chronic limited GvHD did not occur in any patient, but extensive occurred in the 5 patients developing acute GvHD. None of the patients had chronic GvHD at 18 months. VOD occurred in 4 patients (33.3%) and responded to standard measures and defibrotide treatment. The median neutrophil engraftment was 13 days (range 9 to 22). Patient with sickle cell disease had the platelet count maintained >50 x 109/L at all times. The median platelet engraftment >50 x 109/L was 37 days (range 15 to 86) and >50 x 109/L was 32 days (range 15 to 111). The median time to cessation of immunosuppression was 134 days (68-219).
Chimerism studies on day +28 demonstrated 100% in whole blood (WB) and 88.9% in T cells (T) >95%, and 0% WB and 11.1% T >50-89% [n=11]; day +90: 91.7% WB and 91.7% T >95%, 8.3% WB and 0% T >50-89%, 0% WB and 8.3% T <50% [n=12]; day +180: 91.7% WB and 91.7% T >95%, and 8.3% WB and 8.3% T >50-89% [n=12]; and day +365: 50% WB and 50% T >95%, 25% WB and 25% T >90-95%, and 25% WB and 25% T >50-89% [n=4].
In conclusion, unrelated bone marrow transplantation for all haemoglobinopathies is feasible and the overall survival and disease-free survival is 90.9%. FTTA leads to early and sustained engraftment with low rate of graft failure, and whilst the occurrence of VOD despite adequate chelation pre-transplantation and the incidence of GvHD was significant, these complications resolved with standard therapies and long-term outcomes approach those of related transplantation with no treatment required by 18 months.
Disclosures: No relevant conflicts of interest to declare.
See more of: Thalassemia and Globin Gene Regulation
See more of: Oral and Poster Abstracts