Clinical trial: switch to combined mycophenolate mofetil and minimal dose calcineurin inhibitor in stable liver transplant patients--assessment of renal and allograft function, cardiovascular risk factors and immune monitoring

BACKGROUND: Calcineurin inhibitor (CNI)-related nephrotoxicity significantly contributes to chronic renal failure after liver transplantation. METHODS: In this prospective study, liver transplantation patients with renal dysfunction were randomized either to receive mycophenolate mofetil (MMF) followed by stepwise reduction of CNI with defined minimal CNI-trough levels (MMF group), or to continue their maintenance CNI dose (control group). Immune monitoring was performed in a subgroup of the patients. RESULTS: In the MMF group (n = 50), renal function assessed by serum creatinine improved >10% in 62% of patients, was stable in 36% and deteriorated >10% in 2% after 12 months compared with baseline values. Mean serum creatinine levels (+/- s.d.) significantly decreased from 1.90 +/- 0.44 mg/dL to 1.61 +/- 0.39 mg/dL and the corresponding calculated glomerular filtration rate significantly increased from 38.8 +/- 9.6 mL/min/1.73 m(2) to 47.0 +/- 11.8 mL/min/1.73 m(2) over a 12-month follow-up period. Blood pressure and levels of liver enzymes significantly decreased. In the control group (n = 25), there were no significant changes with respect to the investigated parameters. The MMF group had significantly lower numbers of circulating cytotoxic T cells compared with the controls; whereas regulatory T cells significantly increased. CONCLUSION: Combined MMF and minimal dose CNI therapy after liver transplantation is nephroprotective and may promote allograft tolerance.