Buprenorphine transdermal system in adults with chronic low back pain: a randomized, double-blind, placebo-controlled crossover study, followed by an open-label extension phase.

Background: Buprenorphine is a mixed-activity, partial mu-opioid agonist. Its lipid solubility makes it well suited for transdermal administration.

Objective: This study assessed the efficacy and safety profile of a 7-day buprenorphine transdermal system (BTDS) in adult (age >18 years) patients with moderate to severe chronic low back pain previously treated with > or =1 tablet daily of an opioid analgesic.