Haploidentical Stem Cell Transplantation for Patients With Hematologic Malignancies
Status:
Completed
Trial end date:
2009-01-01
Target enrollment:
Participant gender:
Summary
Blood and marrow stem cell transplant has improved the outcome for patients with high-risk
hematologic malignancies. However, most patients do not have an appropriate HLA (immune type)
matched sibling donor available and/or are unable to identify an acceptable unrelated HLA
matched donor through the registries in a timely manner. Another option is haploidentical
transplant using a partially matched family member donor.
Although haploidentical transplant has proven curative in many patients, this procedure has
been hindered by significant complications, primarily regimen-related toxicity including
graft versus host disease (GVHD) and infection due to delayed immune reconstitution. These
can, in part, be due to certain white blood cells in the graft called T cells. GVHD happens
when the donor T cells recognize the body tissues of the patient (the host) are different and
attack these cells. Although too many T cells increase the possibility of GVHD, too few may
cause the recipient's immune system to reconstitute slowly or the graft to fail to grow,
leaving the patient at high-risk for significant infection.
This research project will investigate the use of particular pre-transplant conditioning
regimen (chemotherapy, antibodies and total body irradiation) followed by a stem cell
infusion from a "mismatched" family member donor. Once these stem cells are obtained they
will be highly purified in an effort to remove T cells using the investigational CliniMACS
stem cell selection device. The primary goal of this study will be to determine the rate of
neutrophil and platelet engraftment, as well as the degree and rate of immune reconstitution
in the first 100 days posttransplant for patients who receive this study treatment.
Researchers will also study ways to decrease complications that may occur with a transplant
from a genetically mismatched family donor.