Assessment of the Pharmacokinetic Profile of Tacrolimus Medications and Their Relation to Effectiveness and Safety in Liver Transplant Patients

Inclusion Criteria: 1. Patients ≥ 18 years of age 2. Patients after liver- or simultaneous liver and kidney transplantation 3. Having received a tacrolimus containing immunosuppressant therapeutic regimen at least for four weeks (induction therapy), and TL is within 5-20 ng/ml before inclusion 4. Patients signed an informed consent form for use of their pseudonymised clinical data within the present non-interventional trial. Exclusion Criteria: 1. Participation in any clinical trial, 30 days prior to inclusion 2. The patients received liver allograft more than 6 months before inclusion 3. Hospitalisation due to infection, acute rejection, or graft disfunction 2 weeks prior to enrolment 4. Chronic graft insufficiency in the patient's history 5. Use of medications 2 weeks prior to enrolment, or the need for continuous use of medications that are known to significantly affect the pharmacokinetics of tacrolimus containing medications (as CYP3A4 inducers: rifampin, carbamazepine, phenobarbital, and phenytoin, or CYP3A4 inhibitors: erythromycin, ketoconazole, clarithromycin, and verapamil containing medication) 6. Presence of the following comorbidities: 1. Diseases affecting adherence to therapy (Chronic neurologic conditions, Psychiatric diseases) 2. Diseases affecting drug absorption and metabolism (Inflammatory bowel disease, Chronic inflammatory diseases of bile ducts, Presence of ascites due to any disease) 7. Patients on waiting list for re-transplantation