Sirolimus in combination with low-dose extended-release tacrolimus in kidney transplant recipients

Introduction: Many challenges remain for long-term survival of renal allografts. Once-daily sirolimus (SRL) combined with low-dose extended-release tacrolimus (LER-TAC) may improve medication adherence and reduce the potential nephrotoxicity of calcineurin inhibitors (CNI) compared with standard immunosuppression regimens, thus potentially improving long-term graft survival.Methods: This retrospective, observational, single-center, propensity score matching (PSM) study compared conversion to SRL combined with low-dose ER-TAC and mycophenolic acid (MPA) combined with standard-dose TAC in kidney transplant recipients. After PSM, there were 56 patients in each group. Efficacy, safety, and medication adherence were evaluated over 12 months.Results: There was no significant difference between the two groups in terms of graft and recipient survival and incidence of biopsy-proven acute rejection (p = 1.000), and none of the recipients developed dnDSA after conversion. The mean eGFR improved in SRL + LER-TAC group after conversion compared to before conversion (51.12 +/- 20.1 ml/min/1.73 m(2) vs. 56.97 +/- 19.23 ml/min/1.73 m(2), p < 0.05). The medication adherence at 12 months after conversion was superior to before conversion (p = 0.002).Discussion: Our findings suggest that an immunosuppressive regimen of SRL combined with low-dose ER-TAC is no less effective and safe than standard immunosuppressive regimens for renal transplant recipients and may improve graft renal function and medication adherence.