European Journal of Clinical Pharmacology

, Volume 66, Issue 11, pp 1119–1130

Effects of uridine diphosphate glucuronosyltransferase 2B7 and 1A7 pharmacogenomics and patient clinical parameters on steady-state mycophenolic acid pharmacokinetics in glomerulonephritis

  • Melanie S. Joy
  • Tammy Boyette
  • Yichun Hu
  • Jinzhao Wang
  • Mary La
  • Susan L. Hogan
  • Paul W. Stewart
  • Ronald J. Falk
  • Mary Anne Dooley
  • Philip C. Smith
Pharmacogenetics

DOI: 10.1007/s00228-010-0846-x

Cite this article as:
Joy, M.S., Boyette, T., Hu, Y. et al. Eur J Clin Pharmacol (2010) 66: 1119. doi:10.1007/s00228-010-0846-x

Abstract

Purpose

The role of pharmacogenomics, clinical and demographic parameters in pharmacokinetic predictions was evaluated in patients receiving mycophenolic acid (MPA).

Methods

A cohort study design of patients with glomerulonephritis secondary to lupus nephritis and anti-neutrophil cytoplasmic antibody (ANCA) vasculitis was employed. Forty-six patients with lupus nephritis and ANCA vasculitis who were receiving MPA were recruited from the nephrology clinic. The study assessed the relative single and combined roles of genomic, clinical, and demographic characteristics on pharmacokinetic parameters using general linear models. The study focused on polymorphisms in UGT1A7, UGT2B7, and ABCB1/MDR1; all of which have limited data available concerning MPA pharmacokinetics. All patients had pharmacokinetic assessments for MPA and glucuronide metabolites (MPAG, AcMPAG). Genotyping was performed for known variants of UGTs (UGT1A9, UGT1A7, UGT2B7), and multidrug resistance protein (ABCB1/MDR1), involved in MPA disposition. Analyses included univariate and multivariate linear modeling.

Results

In univariate analyses, UGT2B7 heterozygosity (coefficient 0.3508; R2=0.0873) and UGT1A7 heterozygosity (coefficient 0.3778; R2=0.0966) predicted increased apparent oral clearance of MPA. UGT1A7 heterozygosity (coefficient −0.4647; R2 0.0897) predicted lower MPA trough concentrations. In multivariate assessments, higher urinary protein excretion, lower serum creatinine, and increased weight predicted greater apparent oral clearance of MPA (p < 0.0001). White race and higher serum creatinine predicted higher MPA trough concentrations (p < 0.0001). Higher exposure to MPA was predicted by decreased urinary protein excretion and increased serum creatinine.

Conclusions

Clinical and demographic parameters were 2–4 times more important in MPA disposition than genotypes and explained 30–40% of the pharmacokinetic parameters.

Keywords

Mycophenolic acidUGT2B7UGT1A7ABCB1MDR1Glomerulonephritis

Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Melanie S. Joy
    • 1
    • 2
    • 4
  • Tammy Boyette
    • 1
  • Yichun Hu
    • 1
  • Jinzhao Wang
    • 1
  • Mary La
    • 1
  • Susan L. Hogan
    • 1
  • Paul W. Stewart
    • 3
  • Ronald J. Falk
    • 1
  • Mary Anne Dooley
    • 1
  • Philip C. Smith
    • 2
  1. 1.School of Medicine, UNC Kidney CenterUniversity of North CarolinaChapel HillUSA
  2. 2.Eshelman School of PharmacyUniversity of North CarolinaChapel HillUSA
  3. 3.School of Public HealthUniversity of North CarolinaChapel HillUSA
  4. 4.Division of Nephrology and Hypertension, Kidney Center, School of MedicineUniversity of North CarolinaChapel HillUSA