A Study of T-Cell Replete, HLA-Mismatched Haploidentical Bone Marrow Transplantation With Post-Transplant Cyclophosphamide for Patients With Severe Aplastic Anemia Lacking HLA-Matched Related Donor
Severe aplastic anemia is a rare and serious form of bone marrow failure related to an immune-mediated mechanism that results in severe pancytopenia and high risk for infections and bleeding. Patients with matched sibling donors for transplantation have a 80-90% chance of survival; however, a response rate with just immunosuppression for those patients lacking suitable HLA-matched related siblings is only 60%. With immunosuppression, only 1/3 of patients are cured, 1/3 are dependent on long term immunosuppression, and the other 1/3 relapse or develop a clonal disorder. Recent studies have shown that using a haploidentical donor for transplantation has good response rates and significantly lower rates of acute and chronic GVHD.
• Availability of 3/6 - 5/6 matched (HLA-A, B, DR) related donor who must have negative HLA cross-match in the host vs. graft direction
• Age \<= 65 years for previously treated and \<= 75 years for previously treated patients
• KPS \>= 70%
• Aplastic Anemia that meets the following criteria:
⁃ Peripheral Blood (must fulfill 2 of 3):
• \<500 PMN/mm3
• \<20,000 platelets
• absolute reticulocyte count \<40,000/microL
⁃ Bone Marrow (must be either):
• markedly hypocellular (\<25% of normal cellularity)
• moderately hypocellular with 70% non-myeloid precursors and patient meets peripheral blood criteria above