Effect of early Switch to Belatacept As Primary Immunosuppressive Regimen Among Calcineurin Inhibitor–Intolerant Lung-Transplant Recipients: A single-center series

Early acute renal failure (ARF) is a common complication after lung transplantation (LTx), and is associated with higher long-term mortality. Calcineurins inhibitors (CNIs) toxicity play a major role in ARF in the early phase post-LTx, and alternate nonnephrotoxic immunosuppressive (IS) regimen are needed in LTx. Belatacept, a novel immunosuppressant that blocks a T-cell costimulation pathway, is a nonnephrotoxic drug indicated as an alternative to CNIs in kidney Tx. In LTx, a few cases of CNI-belatacept conversion have been reported so far, only in the late long-term follow-up (>3 years post-LTx). We here report a single-center series of 4 LTx recipients converted to a belatacept primary IS-regimen in the early-postoperative period after LTx (month [M] 2, M2, M2, M5). Causes of conversion were persistent severe renal failure, due to: [1] thrombotic microangiopathy; [2] CNI toxicity/acute tubular necrosis (ATN); [3] ATN/FSglomerulosclerosis; [4] CNI toxicity. Following belatacept-conversion, acute rejection (AR) episodes occurred in 2 high immunologic risk recipients, with detection of donor-specific antibodies (asymptomatic AR both in patient 1 [graded A2B0] and patient 2 [A2Bx], which were both resolved with pulsed steroids). All 4 recipients remained with stable pulmonary function and significant renal function improvement at last available follow-up postbelatacept (M2, M3, M3, and M4). Outcome at 9 months postbelatacept, including incidence of AR and chronic lung allograft dysfunction, graft survival, and renal function outcome will be presented at the ERS 2017 congress.