NCT05669001 (ASCEND) tests a CNI-free regimen vs standard of care in de novo kidney transplant. Experimental: TCD601 (siplizumab), a monoclonal antibody against CD2 (biologic), depleting/modulating CD2+ T and NK cells and blocking T-cell co-stimulation/adhesion, plus belatacept, a CTLA4-Ig fusion protein (biologic) that blocks CD80/86–CD28 co-stimulation on APCs, with mycophenolic acid (small-molecule antimetabolite, IMPDH inhibitor) to curb lymphocyte proliferation, and corticosteroids (steroidal immunosuppressants, glucocorticoid receptor–mediated cytokine suppression). Comparator: ATG (polyclonal antibody, T-cell depletion) + tacrolimus (small-molecule calcineurin inhibitor, NFAT/IL‑2 blockade) + MPA + steroids. Targets: CD2, CD80/86–CD28, calcineurin–NFAT, de novo purine synthesis, glucocorticoid pathways, primary cells: T cells (and NK cells).