Interindividual variability in pharmacokinetics of generic nucleoside reverse transcriptase inhibitors in TB/HIV-coinfected Ghanaian patients: UGT2B7*1c is associated with faster zidovudine clearance and glucuronidation

J Clin Pharmacol. 2009 Sep;49(9):1079-90. doi: 10.1177/0091270009338482. Epub 2009 Jul 23.

Abstract

There are limited data on the pharmacokinetics of generic nucleoside reverse transcriptase inhibitors (NRTIs) in native African populations, in whom they are commonly used. The authors characterized the pharmacokinetics of lamivudine (n = 27), zidovudine (n = 16), and stavudine (n = 11) in human immunodeficiency virus (HIV)/tuberculosis (TB)-coinfected Ghanaians and evaluated associations between zidovudine metabolism and UDP-glucuronosyltransferase (UGT) 2B7 polymorphisms. Lamivudine, zidovudine, and stavudine apparent oral clearance (CL/F) values (mean +/- SD [% coefficient of variation [CV]) were 7.3 +/- 2.8 (39%), 31.9 +/- 33.6 (106%), and 16.4 +/- 5.8 (35%) mL/min/kg, respectively, whereas half-life values were 4.2 +/- 1.9 (46%), 8.1 +/- 7.9 (98%), and 1.5 +/- 1.0 (65%) hours, respectively. Zidovudine CL/F was 196% higher (P = .004) in UGT2B7*1c (c.735A>G) carriers versus noncarriers. This was confirmed using human liver bank samples (n = 52), which showed 48% higher (P = .020) zidovudine glucuronidation and 33% higher (P = .015) UGT2B7 protein in UGT2B7*1c carriers versus noncarriers. In conclusion, generic NRTI pharmacokinetics in HIV/TB-coinfected Ghanaians are similar to other populations, whereas the UGT2B7*1c polymorphism may explain in part relatively high interindividual variability in zidovudine clearance.

Publication types

  • Clinical Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • AIDS-Related Opportunistic Infections / drug therapy
  • Adult
  • Drug Combinations
  • Drug Therapy, Combination
  • Drugs, Generic / pharmacokinetics
  • Drugs, Generic / therapeutic use
  • Female
  • Ghana
  • Glucuronides / metabolism
  • Glucuronosyltransferase / genetics
  • HIV Infections / complications
  • HIV Infections / drug therapy
  • Half-Life
  • Humans
  • Lamivudine / administration & dosage
  • Lamivudine / pharmacokinetics*
  • Lamivudine / therapeutic use
  • Liver / metabolism
  • Male
  • Middle Aged
  • Polymorphism, Genetic
  • Reverse Transcriptase Inhibitors / administration & dosage
  • Reverse Transcriptase Inhibitors / pharmacokinetics*
  • Reverse Transcriptase Inhibitors / therapeutic use
  • Stavudine / administration & dosage
  • Stavudine / pharmacokinetics*
  • Stavudine / therapeutic use
  • Tuberculosis / drug therapy
  • Tuberculosis / etiology
  • Zidovudine / administration & dosage
  • Zidovudine / pharmacokinetics*
  • Zidovudine / therapeutic use

Substances

  • Drug Combinations
  • Drugs, Generic
  • Glucuronides
  • Reverse Transcriptase Inhibitors
  • Lamivudine
  • Zidovudine
  • Stavudine
  • UGT2B7 protein, human
  • Glucuronosyltransferase