NCJ Number
196561
Journal
American Journal on Addictions Volume: 11 Issue: 1 Dated: Winter 2002 Pages: 66-74
Date Published
2001
Length
9 pages
Annotation
Methadone pharmacokinetics were determined in an open-label, within-subject study in 16 methadone-maintained, non-HIV-infected subjects prior to and following administration of one lamivudine 150-mg/zidovudine 300-mg combination tablet to determine whether this antiretroviral therapy alters methadone serum concentrations.
Abstract
Male and female subjects could be enrolled in this study if they were HIV-seronegative by antibody enzyme-linked immunosorbent assay (ELISA), were 18 to 55 years of age, weighed a minimum of 110 pounds if male and 90 pounds if female, met DSM-IV criteria for opioid dependence, and were enrolled in a certified methadone maintenance program with a current methadone dose that had been unchanged for at least 21 days prestudy. The study was open-label and within-subject design, with subjects serving as their own controls. All 16 subjects completed the study. Methadone serum concentrations were determined by high-performance liquid chromatography. Methadone pharmacokinetic parameters were evaluated for each subject after taking methadone only and after the same dose taken concomitantly with a single dose of the lamivudine/zidovudine combination tablet. This tablet has been introduced for twice-daily use in an effort to reduce pill burden and thereby facilitate improved adherence in patients on antiretroviral therapy. This study detected no differences in the mean area under the serum concentration-time curve, oral clearance, oral volume of distribution, maximum serum concentration, or terminal elimination half-life. These findings suggest that methadone dose change is not likely to be necessary for patients treated with lamivudine/zidovudine combination pharmacotherapy. 1 table, 1 figure, and 35 references