Buprenorphine implants reduce opioid use of opioid-dependent patients

In a new randomized, placebo-controlled clinical trial published in the October 13, 2010 Journal of the American Medical Association, trial investigators demonstrated that the use of buprenorphine implants (Probuphine, Titan Pharmaceuticals) could reduce opioid use over a 24-week study period.  In fact, opioid-dependent patients receiving buprenorphine implants were 30% more likely to have a negative urine sample test for illicit opioid than those receiving placebo implants.

“The introduction of buprenorphine into clinical practice is arguably the most significant improvement in the treatment of opioid addiction in the last decade; however, physicians excited with the clinical success of buprenorphine are also rightfully concerned about medication adherence and diversion-and potential for abuse-of the sublingual formulations of buprenorphine,” said Walter Ling, MD, professor of psychiatry and director, Integrated Substance Abuse Programs at the David Geffen School of Medicine at UCLA and the paper’s lead author. “Probuphine does away with these concerns by eliminating the need for take-home doses. He continued, “Additionally, by providing a sustained blood level of active medication, Probuphine helps diminish the daily fluctuation of the medication effects-and potentially side effects-and reduces the total exposure of buprenorphine over time.”

After a 4-week run-in phase using sublingual buprenorphine/naloxone tablets, trial investigators randomly assigned a total of 163 opioid-dependent adults to receive 4 (or 5 if needed) buprenorphine implants (n=108) containing 80 mg of drug per implant or placebo implants (n=55), both in conjunction with personalized drug counseling. 

The trial investigators noted in their paper, “Of particular clinical importance are the favorable urinalysis toxicology results and the good patient retention.” 

Patients receiving the buprenorphine implants had significantly more urine samples test negative for illicit opioid use during weeks 1 to 16 (40.4% vs 28.3% P=.04), the trial’s primary end point. Similar results were seen during the full 24 weeks trial period (36.6% vs 22.4%, P=.01).

Moreover, patients receiving buprenorphine implants were more than twice as likely to complete the trial (65.7% vs 30.9%, P<.001), report less withdrawal symptoms (P=.004) and cravings (P<.001), and exhibit superior improvements in clinician global ratings of severity of opioid dependence (P<.001) and improvement (P<.001).

In regard to safety, minor implant site reactions were the most common adverse events reported and were seen in similar proportions of buprenorphine and placebo implant participants (56.5% vs 52.7%, P=.65). Serious adverse events occurred in fewer than 2% of buprenorphine implant participants.

According to the World Health Organization (WHO), more than 2 million Americans are addicted to prescription opiates and nearly 3 million individuals in the United States and Europe are addicted to illicit opiates.