title: Effect of CYP3A4*22, CYP3A5*3, and CYP3A Combined Genotypes on Cyclosporine, Everolimus, and Tacrolimus Pharmacokinetics in Renal Transplantation.
abstract: Cyclosporine, everolimus, and tacrolimus are the cornerstone of immunosuppressive therapy in renal transplantation. These drugs are characterized by narrow therapeutic windows, highly variable pharmacokinetics (PK), and metabolism by CYP3A enzymes. Recently, the decreased activity allele, CYP3A4*22, was described as a potential predictive marker for CYP3A4 activity. This study investigated the effect of CYP3A4*22, CYP3A5*3, and CYP3A combined genotypes on cyclosporine, everolimus, and tacrolimus PK in renal transplant patients. CYP3A4*22 carriers showed a significant lower clearance for cyclosporine (-15%), and a trend was observed for everolimus (-7%) and tacrolimus (-16%). Patients carrying at least one CYP3A5*1 allele had 1.5-fold higher tacrolimus clearance compared with noncarriers; however, CYP3A5*3 appeared to be nonpredictive for everolimus and cyclosporine. CYP3A combined genotype did not significantly improve prediction of clearance compared with CYP3A5*3 or CYP3A4*22 alone. These data suggest that dose individualization of cyclosporine, everolimus, or tacrolimus therapy based on CYP3A4*22 is not indicated.CPT: Pharmacometrics Systems Pharmacology (2014); 3, e100; doi:10.1038/psp.2013.78; published online 12 February 2014.
authors: 1] Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands [2] Department of Nephrology, Leiden University Medical Center, Leiden, The Netherlands.
authors: D J A R
authors: DJ
authors: Moes
authors: 1] Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands [2] Department of Nephrology, Leiden University Medical Center, Leiden, The Netherlands.
authors: J J
authors: JJ
authors: Swen
authors: Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands.
authors: J
authors: J
authors: den Hartigh
authors: Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands.
authors: T
authors: T
authors: van der Straaten
authors: Department of Nephrology, Academic Medical Center, Amsterdam, The Netherlands.
authors: J J Homan
authors: JJ
authors: van der Heide
authors: Department of Nephrology, University Medical Center Groningen, Groningen, The Netherlands.
authors: J S
authors: JS
authors: Sanders
authors: Department of Nephrology, Academic Medical Center, Amsterdam, The Netherlands.
authors: F J
authors: FJ
authors: Bemelman
authors: Department of Nephrology, Leiden University Medical Center, Leiden, The Netherlands.
authors: J W
authors: JW
authors: de Fijter
authors: Department of Clinical Pharmacy and Toxicology, Leiden University Medical Center, Leiden, The Netherlands.
authors: H J
authors: HJ
authors: Guchelaar