Medical treatments for opioid use disorder in Iran: a randomized, double-blind placebo-controlled comparison of buprenorphine/naloxone and naltrexone maintenance treatment.

AIMS: With the broad goals of developing a clinical research and training program and disseminating effective opioid use disorder treatments in Iran, this pilot clinical trial compared the effectiveness of oral naltrexone (NTX) and sublingual buprenorphine/naloxone (BNX). DESIGN: Twelve-week single-site, two-group parallel randomized double-blind clinical trial. SETTING: An out-patient clinical research program in Tehran, Iran. PARTICIPANTS: Following medically assisted withdrawal, participants with opioid use disorder were assigned randomly to NTX (n = 51) or BNX (n = 51). INTERVENTION: Medications were administered three times per week, double-blind, double-dummy for 12 weeks. All participants received weekly group drug counseling. MEASUREMENTS: The primary outcome was initial duration of opioid abstinence verified by urine toxicology tests. Secondary outcomes included the number of opioid-negative urine tests, treatment retention and proportions with sustained, verified opioid-abstinence for 12 weeks. FINDINGS: Mean [95% confidence interval (CI)] number of days of initial duration of verified abstinence was 28.8 (20.0-37.5) with BNX and 21.6 (14.4-28.7) with NTX (P = 0.205). The mean (95% CI) number of opioid-negative urine tests was 19.7 (17.7-21.6) with BNX and 15.4 (13.1-17.8) with NTX (P = 0.049). The mean (95% CI) number of days in treatment was 70.6 (63.6-77.7) with BNX versus 56.5 (47.8-65.3) with NTX (P = 0.013). The rate of sustained, 12-week opioid abstinence was 16% (8/51) in the BNX group and 8% (4/51) in the NTX group (P = 0.219). CONCLUSIONS: Among patients with opioid use disorder in Iran, sublingual buprenorphine/naloxone was associated with a greater number of opioid-negative urine tests and treatment retention than oral naltrexone, but not significantly greater initial abstinence duration or proportions with sustained abstinence.