Kidney transplant rejection rates and renal graft outcomes have dramatically improved over the past 15 years due to the use of antibody induction therapy and calcineurin inhibitors (CNIs). Unfortunately, the potent immunosuppression induced by these drugs increases the risk of malignancies, infections and nephrotoxicity. While current clinical protocols try to reduce CNI exposure, little is known about the safety of antibody induction avoidance and CNI withdrawal.
A recent study by researchers at Washington University and St. Louis University led by Assistant Professor of Medicine Tarek Alhamad found that calcineurin inhibitors could be withdrawn in a certain low-risk population of kidney transplant patients: white patients who receive 2-haplotype HLA-matched living kidney grafts. Published in Transplantation Direct, the study confirms earlier research, but extends the findings to also show that this patient group does not need antibody-induction therapy and that CNIs can be withdrawn between 6 to 12 months post-transplant.
The risk of kidney transplant failure is determined by a variety of factors, both epidemiological (race, age) and immunological (panel-reactive antibody levels, ABO and HLA compatibility). White patients who receive 2-haplotype HLA-matched living kidney grafts are among one of the most low-risk immunologic risk groups of kidney transplant patients.
“This study was the largest single-center experience of induction avoidance in this population of kidney transplantation,” says Dr. Alhamad. “The unique thing about this study is that we compared our single-center experience with a large pool of patients with and without induction captured in the national Organ Procurement and Transplantation Network registry.”
Results of this study may help clinicians tailor a personalized therapeutic strategy for this population of kidney transplant patients. “We will continue to work to find new strategies that will prolong the graft survival and reduce the side effects of immunosuppression medications,” says Dr. Alhamad.
Rowena Delos Santos
The article, The Privilege of Induction Avoidance and Calcineurin Inhibitors Withdrawal in 2 Haplotype HLA Matched White Kidney Transplantation, can be read in full here. Authors: Zaid Brifkani, MD; Daniel C. Brennan, MD; Krista L. Lentine, MD, PhD; Timothy A. Horwedel; Andrew F. Malone, MD; Rowena Delos Santos, MD; Thin Thin Maw, MD; and Tarek Alhamad, MD, MS.