Factors associated with altered pharmacokinetics in substance users and non-substance users receiving lopinavir and atazanavir

Niamh Higgins, Barry S. Zingman, Judianne Slish, Richard C. Reichman, Margaret A. Fischl, Barbara Gripshover, Kelly Tooley, Naomi Boston, Alan Forrest, Dan Brazeau, Linda M. Catanzaro, Robin DiFrancesco, Francesco Lliguicota, Qing Ma, Gene D. Morse

Research output: Contribution to journalArticle

10 Scopus citations


Substance use is highly prevalent in HIV-infected individuals in the United States, and clinical management is complicated by the need for antiretroviral treatment, addiction therapy, variable medication adherence, and co-morbidities. The interrelation between HIV and substance use prompted our investigation to examine substance use and self-reported medication adherence in patients receiving the HIV-1 protease inhibitors, atazanavir (ATV) or lopinavir (LPV). ATV and LPV pharmacokinetics were determined by measuring plasma concentrations in subjects with active substance use (SU group) or with no active substance use (NSU group). No difference in adherence was observed between groups (p > 0.05). The mean SU ATV trough was 0.550±0.45 μg/mL; the mean NSU ATV trough was 0.780±0.590 μg/mL (p > 0.05). The mean SU LPV trough was 4.02±2.39 μg/mL; the mean NSU LPV trough was 6.67±0.910 μg/mL (p = 0.01). Co-factors found to be associated with variation in ATV and LPV concentrations included concurrent methadone use, cigarette smoking, and substance use status. These data indicate that chronic HIV treatment may be assisted with plasma concentration monitoring to identify those patients who may require dosage modification and/or regimen adjustment in order to optimize antiretroviral effects.

Original languageEnglish (US)
Pages (from-to)488-494
Number of pages7
JournalAmerican Journal on Addictions
Issue number6
Publication statusPublished - Nov 1 2007


ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Clinical Psychology
  • Psychiatry and Mental health

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