Medication-assisted treatment for opioid addiction: Methadone and buprenorphine

Among agents for opioid addiction treatment, methadone is a full μ-opioid receptor agonist, whereas buprenorphine is a partial agonist. Both are long-acting agents. Buprenorphine has a superior safety profile. Methadone is formulated for oral administration and buprenorphine is formulated for sublingual administration. The U.S. Food and Drug Administration is considering for approval a subdermal buprenorphine implant that has a six-month duration of action. Both medications reduce mortality rates and improve other outcomes. Data from a recent randomized, controlled comparison study (N = 1269) of both medications show better treatment retention with methadone, but reduced illicit opioid use early in treatment with buprenorphine. Risk behaviors for human immunodeficiency virus (HIV) were measured by using the Risk Behavior Survey at baseline, at 12 weeks, and at 24 weeks for study completers. In the 30 days prior to entering treatment, 14.4% of the completers (n = 340) who were randomized to treatment with buprenorphine had shared needles and 14.1% of the completers (n = 391) who were randomized to methadone treatment had shared needles. In the 30 days prior to Week 24, the percentage of patients sharing needles decreased to 2.4% for the buprenorphine group and 4.8% for the methadone group (p < 0.0001). In the 30 days prior to entering treatment, 6.8% of the completers randomized to buprenorphine and 8.2% of the completers randomized to methadone had multiple sexual partners; at Week 24, only 5.2% and 5.1%, respectively, reported multiple partners (p < 0.04).