2019: Articles in Press
Research Article

Tacrolimus Pharmacokinetics in Living-Donor and Deceased-Donor Liver Transplant in Saudi Patients

Abou-Auda HS
College of Pharmacy, King Saud University, Riyadh, Saudi Arabia
Qaddour E
College of pharmacy, Riyadh Elm University, Riyadh, Saudi Arabia
Alsisi H
Liver Transplant Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
Ajlan A
Solid organ Transplant, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
Alsebayel M
Liver Transplant Department, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia
Published April 8, 2019

Abstract

Introduction: Tacrolimus is a macrolide immunosuppressant. It has a narrow therapeutic index and serious side effects which necessitate monitoring of tacrolimus blood concentration. The trough concentration of the drug may also differ based on the type of liver transplant. This study was conducted to investigate differences in pharmacokinetics between transplant types and to determine tacrolimus population pharmacokinetic in liver transplant recipients in Saudi Arabia.
Method: Patients on tacrolimus, as the main immunosuppressant, who underwent liver transplant throughout2012-2014 were retrospectively studied. Demographic characteristic, tacrolimus blood trough concentrations, liver, renal, biochemistry, and hematology lab results were all collected. The pharmacokinetic parameters were estimated assuming one compartment model.
Results: Tacrolimus pharmacokinetic parameters were found to be as following; elimination rate constant () 0.094 ±  0.0123, apparent volume of distribution () 112.48±63.033 L/hr, elimination half-life () 7.46± 1.01 hr and apparent total body clearance () 10.27± 5.69 L/hr (mean ± SD). Statistically significant difference was found between living-donor and deceased-donor liver transplant with respect to apparent clearance and apparent volume of distribution. Living-donor liver transplant recipients have apparent volume of distribution of 97.39±47.00 L (mean ± SD) and an apparent clearance of 8.89±4.24L/hr (mean± SD). On the other hand, deceased-donor liver transplant has an apparent clearance of 12.97±7.09L/hr (mean ± SD) and an apparent volume of distribution of 142.17± 78.65 L (mean ± SD).
Conclusions: Tacrolimus pharmacokinetics parameters were accurately determined in liver transplant recipients in Saudi Arabia. The results of the present study can be clinically used in the therapeutic drug monitoring of tacrolimus in the individualization of drug dosage and taking the appropriate clinical decisions to prevent allograft rejection.