Buprenorphine implant may improve opioid abstinence over daily sublingual buprenorphine

Buprenorphine implants may be an effective alternative relapse prevention treatment for stable, opioid-dependent adults who use 8 mg or less of sublingual buprenorphine daily, an industry-funded study found.

To determine whether 6-month buprenorphine implants were noninferior to daily sublingual buprenorphine as maintenance treatment for opioid-dependent patients with stable abstinence, 177 opioid-dependent outpatients were randomly assigned to sublingual buprenorphine with placebo implants (n=90) or to buprenorphine implants (4 simultaneously placed, 26×2.5-mm implants of buprenorphine hydrochloride, 80 mg each, expected efficacy of 24 weeks) with sublingual placebo (n=87). The 24-week, double-blind, double-dummy study was conducted at 21 U.S. sites from June 2014 through May 2015.

The primary end point was between-group difference in proportion of responders (≥4 of 6 months without opioid-positive urine test result, monthly and 4 times randomly, and self-report). The secondary end points included cumulative percentage of negative opioid urine results, abstinence, and time to first illicit opioid use.

This study was funded by Braeburn Pharmaceuticals, and researchers reported financial and nonfinancial support or employment from pharmaceutical companies, including Braeburn. Results appeared in the July 19 JAMA.

Eighty-one of 84 patients (96%) receiving buprenorphine implants and 78 of 89 (88%) receiving sublingual buprenorphine responded to treatment, as confirmed by urine tests and self-report. Over 6 months, 72 of 84 (86%) receiving buprenorphine implants and 64 of 89 (72%) receiving sublingual buprenorphine maintained opioid abstinence. Non-implant-related and implant-related adverse events occurred in 48% and 23% of the buprenorphine implant group and in 53% and 13.5% of participants in the sublingual buprenorphine group, respectively.

The researchers noted that, while buprenorphine is an effective treatment for opioid dependence, adhering to daily dosing for management of chronic disorders is challenging. “Among adults with opioid dependence maintaining abstinence with a stable dose of sublingual buprenorphine, the use of buprenorphine implants compared with continued sublingual buprenorphine did not result in an inferior likelihood of remaining a responder,” researchers wrote. “However, the study population had an exceptionally high response rate in the control group, and further studies are needed in broader populations to assess the efficacy in other settings.”

An editorial noted that the implants may support patients' decision-making deficits, which are a core component of the addiction. The FDA recently approved them for up to 1 year of treatment for patients who have already achieved and sustained prolonged clinical stability while receiving low to moderate doses of oral transmucosal buprenorphine.

“Even so, this novel approach to delivering care may open up treatment for new, previously difficult-to-reach populations or for those in the criminal justice system,” the editorialists wrote. “Although further research is needed to determine which populations would benefit the most from these new formulations, the potential of these agents to have a positive role in the current opioid crisis is undeniable.”