Pharmacokinetics of mycophenolic acid in live donor liver transplant patients vs deceased donor liver transplant patients

The exposure of mycophenolic acid in live donor liver transplant patients (those receiving a partial hepatic volume) in comparison to deceased donor liver transplant patients (those receiving the whole hepatic volume) after administration of mycophenolate mofetil has not been reported earlier. The aim of the present study is to compare the pharmacokinetics parameters of mycophenolic acid and mycophenolic acid glucuronide in live donor liver transplant patients versus deceased donor liver transplant patients. Twelve live donor liver transplant and 12 deceased donor liver transplant recipients were studied over a dosing interval after intravenous administration of mycophenolate mofetil. The maximum concentration (C_max) and the area under the plasma concentration versus time curve (AUC) for mycophenolic acid in live donor liver transplant patients were significantly higher than in deceased donor liver transplant patients (C_max/AUC: live donor liver transplant patients: 16.1 ± 6.6 μg/mL/43.9 ± 12.6 μg/mL·h vs deceased donor liver transplant patients: 10.7 ± 2.0 μg/mL/28.9 ± 7.1 μg/mL·h; P =.046/.002). The volume of distribution was higher in the deceased donor liver transplant patients compared with live donor liver transplant patients. However, the mean plasma concentration at 12 hours (C_last), drug disposition rate constant, half-life (t_1/2), and mean residence time were similar in both groups. The mean plasma concentration of mycophenolic acid glucuronide was 1.4 to 2.0 times higher in deceased donor liver transplant patients compared with live donor liver transplant patients. These observations point to the need to use a lower dosage (approximately 30%) of mycophenolate mofetil in live donor liver transplant patients compared with deceased donor liver transplant patients.