Population pharmacokinetic characteristics of tacrolimus in Chinese lung transplant recipients and optimisation of dosing regimen during the early post-transplantation phase
摘要
This study aimed to establish a population pharmacokinetic model and optimise tacrolimus dosing regimens in Chinese lung transplant recipients.
MethodsA total of 988 tacrolimus trough concentrations and clinical data of 142 adult lung transplant recipients were collected. Population pharmacokinetic analysis was performed using a nonlinear mixed effects model. A Monte Carlo simulation was conducted to determine the optimal dosing regimen.
ResultsThe pharmacokinetics of tacrolimus could be best described by a one-compartment model with first-order absorption and elimination. The typical population parameter estimates of apparent clearance and apparent volume of distribution were 7.58 L·h−1 and 701.39 L, respectively. The clearance of tacrolimus in rapid and intermediate metabolisers of CYP3A5 was 2.72-fold and 1.87-fold higher, respectively, than in poor metabolisers of CYP3A5. The concurrent use of voriconazole, posaconazole, and itraconazole led to a reduction in tacrolimus clearance by 38.21%, 26.30%, and 57.98%, respectively. Recommended dose regimens were obtained by Monte Carlo simulation based on the established model.
ConclusionRecipients with the CYP3A5*3/*3 genotype, elevated haematocrit levels, short postoperative days, and concurrent administration of azole antifungal drugs needed a reduced maintenance dose to reach the therapeutic window, which provided a reference for the formulation of individualised tacrolimus regimen during the early post-transplantation phase.