A. Hsiao1, J. Ortiz1, G. Petrossian1, K. Addonizio1, L. Teixeira1, A. Chiodo Ortiz1, N. Koizumi2, D. Conti1, R. Plews1 1Albany Medical Center, Division Of Renal And Pancreatic Transplant Services, Albany, NY, USA 2George Mason University, Schar School Of Policy And Government, Fairfax, VA, USA
Introduction: Belatacept-based immunosuppression is commonly employed to minimize or eliminate Calcineurin Inhibitor (CNI) utilization and thus limit CNI-associated nephrotoxicity. Belatacept binds to CD80/CD86 on antigen-presenting cells, competitively blocking T cells from binding to APCs through CD28/CD152. While BK Viremia is a potential consequence of immunosuppression, limited data exists regarding the relationship between maintenance Belatacept therapy and BK Viremia in renal transplantation.
Methods: Between 8/6/2011 and 6/4/2021, 143 kidney transplant patients at a single academic medical center were treated with a maintenance therapy regimen that included Belatacept in addition to low-dose Tacrolimus and Mycophenolate Mofetil. Past histories of cardiovascular disease (atrial fibrillation, heart failure, pulmonary embolus, valve/coronary disease), hypertension, hyperlipidemia, diabetes, and obesity were obtained. BK Viremia was tested using real-time PCR with a positive value of over 100 copies/mL.
Results: In this cohort of 143 participants, 93 were male and 50 were female. The average age was 50.13 years. 99 patients identified as white (69.2%), 31 as African American (21.7%), 5 as Latinx (3.5%), and 8 as Asian (5.6%). 56 (39.1%) individuals had a history of CVD, 141 (98.6%) had history of HTN, 92 (64.3%) had HLD, 44 (30.7%) had diabetes, and 63 (44.1%). were obese. 28 (19.6%) subjects experienced delayed graft function after transplantation, defined as the need for dialysis within one week of transplant. Of note, the patients who contracted BK viremia were found to be taking a significantly higher dose of Belatacept (436 mg vs. 401 mg, p=0.04). In this cohort, Asian patients treated with Belatacept were 6 times more likely to develop BK viremia (p=.01), and individuals with CVD were 3 times more likely to develop BK viremia (p=.04).
Conclusion: Preliminary data from this cohort demonstrate that higher doses of Belatacept are associated with greater incidence of BK Viremia. Analyses within this population also suggest that transplant patients of Asian descent and those with a history of CVD are at an increased risk of BK viremia when treated with a Belatacept-based immunosuppression regimen. Future research should be done to explore the course of BK Viremia and the potential implications on graft function in patients receiving Belatacept therapy compared to those receiving CNI maintenance therapy alone.