Pharmacokinetic comparison of the buprenorphine sublingual liquid and tablet

Buprenorphine is a mu opioid partial agonist being developed as a treatment for opioid dependence. Buprenorphine, usually administered as a sublingual liquid, is now being developed as a sublingual tablet for clinical use. The present study compared participants' plasma concentrations after daily maintenance on three buprenorphine liquid doses (2, 4 and 8 mg) and one tablet dose (8 mg). Fourteen opioid-dependent individuals (11 males, three females) participated. Plasma samples were collected over a 24-h period after at least 7 days of maintenance on each dose. Results showed that the liquid doses produced dose-related increases in plasma concentrations. The 8-mg tablet produced mean plasma concentrations significantly lower than those of the 8-mg liquid, although there was substantial individual variability. Thus, the buprenorphine tablet dose might have to be adjusted to produce plasma concentrations equivalent to those of the liquid. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.