title: Pharmacokinetics of buprenorphine: a comparison of sublingual tablet versus liquid after chronic dosing.
abstract: Although buprenorphine is approved for use in the outpatient treatment of opioid addiction in 2 tablet formulations, a monoproduct containing buprenorphine only (Subutex) and a buprenorphine/naloxone combination product (Suboxone), much of the clinical data that support the approval by the U.S. Food and Drug Administration were generated by using a sublingual liquid. To interpret the literature in prescribing parameters for tablet buprenorphine, this study was designed to determine steady state buprenorphine plasma levels for the 2 formulations and to assess the relative bioavailability of each. A randomized, double-blind, crossover study with dose increases was conducted during a 12-week period at an outpatient treatment clinic. Of the 184 subjects initially randomized to treatment, 133 (72.3%) were evaluated for the steady-state trough plasma concentration, 16 (8.7%) for relative bioavailability, and 31 (16.8%) for dose proportionality. At steady state, differences in the trough plasma concentrations of buprenorphine between the 2 formulations were found across all the dose levels. Average plasma concentration (Cavg) of the tablet at twice the milligram dose of the liquid was twice that of the liquid; intersubject variability was greater for the tablet. At double the dose of tablet, there is no difference in steady state plasma concentrations. The bioavailability seems equivalent for the 2 formulations across all the dose levels.
authors.affiliation: From the UCLA School of Nursing (PC), Los Angeles, CA; UCLA Integrated Substance Abuse Programs (WL, DL, CC), Los Angeles, CA; Division of Pharmacotherapies and Medical Consequences of Drug Abuse (CNC), National Institute on Drug Abuse, Bethesda, MD; Center for Human Toxicology (DEM), University of Utah, Salt Lake City, UT; and University of Washington (AH), Drug and Alcohol Institute, Seattle, WA.
authors.forename: Peggy
authors.initials: P
authors.lastname: Compton
authors.forename: Walter
authors.initials: W
authors.lastname: Ling
authors.forename: C Nora
authors.initials: CN
authors.lastname: Chiang
authors.forename: David E
authors.initials: DE
authors.lastname: Moody
authors.forename: Alice
authors.initials: A
authors.lastname: Huber
authors.forename: Debbie
authors.initials: D
authors.lastname: Ling
authors.forename: Charles
authors.initials: C
authors.lastname: Charuvastra