Pretransplant desensitization of donor-specific anti-HLA antibodies with plasmapheresis and immunoglobulin produces equivalent outcomes to patients with no donor specific antibodies in haploidentical hematopoietic cell transplant
Hunter Cassidy Cochran, MD, Hematology-Oncology Fellow, was recently published in Leukemia & Lymphoma.
In many hematologic malignancies, hematopoietic cell transplant (HCT) is the only curative option. The likelihood of finding an optimal donor for whites of European descent is 75%, compared to those of African descent, where the probability of finding a full matched donor is less than 20%. In those without a fully matched donor available, HLA mismatched HCTs between relatives, or haploidentical HCTs, have become a potential life-saving option.
However, the presence of pre-existing antibodies to donor HLA (i.e donor-specific antibodies or DSAs) is an increasingly recognized impediment to successful use of HLA-mismatched donors. The manuscript depicts a protocol for desensitizing patients with donor specific antibodies (DSAs) by using a median of 6 sessions of Intravenous Immunoglobulin (IVIg) and plasmapheresis pre- and post-transplant.
The results of the retrospective study show that using IVIg and plasmapheresis in patients with DSAs have similar overall survival (OS) and progression free survival (PFS) when compared to patients without DSAs. This gives patients without an optimal donor pool, primarily minorities, the ability to receive hematopoietic cell transplants. It also mitigates the added risk of rejection, relapse, while maintaining similar rates of overall survival when compared to patients without donor specific antibodies.
“This analysis tackles a common problem in haplo-identical stem cell transplants—what do you do when the recipient has pre-formed antibodies to their only potential stem cell donor AKA donor specific antibodies (DSAs)? Our data tells us that using desensitization (IVIg and plasmapheresis) in patients with DSAs leads to outcomes very similar to patients getting haplo stem cell transplants without the pre-formed antibodies. This can be vital in patients without great donor options.”