Cognitive Outcomes in Stable Renal Transplant Patients Switched fromTacrolimus to Envarsus XR™

Patients with chronic kidney disease most commonly show cognitive impairments involving attention, memory, executive functions, and mental processing speed. Although data have demonstrated improvements in cognition following kidney transplant and the reversibility of the memory problems evidenced in dialysis, neurotoxicity in transplant patients occurs in \>40-50% of the patients treated with tacrolimus. Attention and working memory impairment have been observed in patients treated with sirolimus or tacrolimus, while cyclosporine-treated patients demonstrated performance similar to that of healthy volunteer controls, which may indicate that the cognitive deficit found was partly related to treatment. ENVARSUS XR is a new FDA-approved formulation of tacrolimus. A hallmark difference between ENVARSUS XR and other forms of once- and twice-daily tacrolimus products is the unique, proprietary MeltDose® drug delivery technology (Veloxis Pharmaceuticals, Hørsholm, Denmark) which reduces tacrolimus' particle size to a molecular level. The decreased surface area of the drug particles results in complete absorption and increased bioavailability in a once-daily dosing formulation. In stable kidney transplant patients, ENVARSUS XR pharmacokinetics are characterized by a steadier and more consistent concentration time profile over 24 hours, reduced peak and peak-to-trough fluctuations and similar exposure while benefiting from \~ 20% less total daily dose than twice daily tacrolimus. This open-label, prospective phase clinical trial is designed to evaluate whether switching patients from TAC-IR to ENVARSUS XR treatment improves cognitive function.