Opium tincture versus methadone for opioid agonist treatment: a randomized controlled trial.

AIM: To test if opium tincture (OT) was non-inferior to methadone in retaining participants in opioid agonist treatment (OAT). DESIGN: A Phase III, multi-centre, parallel-group, non-inferiority, double-blind randomized controlled trial with an allocation ratio of 1:1. Participants were provided treatment and followed for a period of 85 days. SETTING: Four OAT clinics in Iran. PARTICIPANTS: Two hundred and four participants with opioid use disorder [mean age (standard deviation) = 37.4 (9.3); female 11.3%] recruited between July 2017 and January 2018. INTERVENTIONS: Participants were assigned to either OT (102) or methadone (102) using a patient-centred flexible dosing strategy. MEASUREMENTS: Treatment retention over 85 days was the primary outcome. Self-reported opioid use outside treatment and occurrence of adverse events (AEs) were the secondary outcomes. FINDINGS: Remaining in treatment at the end of the follow-up were 68.6% in the methadone arm and 59.8% in the OT arm. The relative retention rate of methadone to OT was 1.15 (0.97, 1.36) in both intent-to-treat and per-protocol analyses; non-inferiority was not supported statistically, as the upper bound of the confidence interval exceeded our pre-specified non-inferiority margin (1.25). Opioid use outside treatment was reported by 30.3% of OT (n = 152) and 49.4% of methadone (n = 168) patients, a difference in proportions of -19%: 90% confidence interval (-28%, -10%). The total count of AEs in the OT arm (22 among nine individuals) was significantly higher (P = 0.04) than that in the methadone arm (three among two individuals). Nausea was the most common side effect. CONCLUSION: While this study could not conclude the non-inferiority of opium tincture (OT) to methadone for retaining patients in opioid agonist treatment, OT retained 60% of participants to end of follow-up (85 days) and was superior to methadone in reducing self-reported opioid use outside treatment.

Substance of choice, impact of heroin or opium on treatment retention in a multicentre randomised controlled trial in Iran.

INTRODUCTION: In the Middle East and Asia, illicit opioid use exists across a spectrum between heroin and opium. The impact of primary opioid of choice on opioid agonist treatment retention has not been well evaluated previously, especially for opium tincture, an increasingly popular form of opioid agonist treatment in Iran. This study investigates the relationship between primary opioid of choice, namely heroin or opium, and retention in opium tincture and methadone treatment. METHODS: Participants with opioid use disorder (n = 204) were randomised to receive opium tincture or methadone. All participants were categorised as mainly using opium or heroin. Bivariate analyses between treatment retention and primary opioid of choice (P < 0.05) and logistic regression were conducted. RESULTS: Among the 191 participants included in this analysis, heroin was the primary substance of choice for 135 participants (70.7%) and opium for 56 (29.3%). Bivariate analysis showed that the opium group was more likely to be satisfied with family situation, employed and retained in treatment than the heroin group while less likely to experience incarceration and use multiple substances. When adjusting for covariates, primary opioid of choice was not significantly associated with retention in either methadone or opium tincture treatment arm. DISCUSSION AND CONCLUSIONS: Positive factors, such as employment, housing and family support, seem to collectively explain the higher retention in treatment among those who primarily use opium compared to those who use heroin. To optimise retention in opioid agonist treatment, biopsychosocial care models should be further evaluated to improve psychosocial functioning.