A double-blind, randomized, parallel group study to compare the efficacy, safety and tolerability of slow-release oral morphine versus methadone in opioid-dependent in-patients willing to undergo detoxification. Retention in a low-threshold methadone maintenance program.
Evaluation of the efficacy and safety of slow-release oral morphine (SROM) compared with methadone for detoxification from methadone and SROM maintenance treatment.
                Randomized, double-blind, double-dummy, comparative multi-centre study with parallel groups.
                Three psychiatric hospitals in Austria specializing in in-patient detoxification.
                Male and female opioid dependents (age > 18 years) willing to undergo detoxification from maintenance therapy in order to reach abstinence.
                Abstinence was reached from maintenance treatment by tapered dose reduction of either SROM or methadone over a period of 16 days.
                Efficacy analyses were based on the number of patients per treatment group completing the study, as well as on the control of signs and symptoms of withdrawal [measured using Short Opioid Withdrawal Scale (SOWS)] and suppression of opiate craving. In addition, self-reported somatic and psychic symptoms (measured using Symptom Checklist SCL-90-R) were monitored.
                Of the 208 patients enrolled into the study, 202 were eligible for analysis (SROM: n = 102, methadone: n = 100). Completion rates were 51% in the SROM group and 49% in the methadone group [difference between groups: 2%; 95% confidence interval (CI): -12% to 16%]. The rate of discontinuation in the study was high mainly because of patients voluntarily withdrawing from treatment. No statistically significant differences between treatment groups were found in terms of signs and symptoms of opiate withdrawal, craving for opiates or self-reported symptoms. SROM and methadone were both well tolerated.
                Detoxification from maintenance treatment with tapered dose reduction of SROM is non-inferior to methadone. In 370 opioid-dependent patients included consecutively in a low-threshold methadone maintenance program, the effect of different variables on the retention rate was assessed. The variables included the patients' age, sex, family situation, employment status, length of heroin use, current route of drug consumption, previous treatments, current consumption of cocaine, alcohol and benzodiazepines, needle sharing, HIV serostatus and methadone dose. The retention rate after 2 years of methadone maintenance was 72%. Dose of methadone > 80 mg/day, age > 30 years, living with family or stable partner and non-current use of alcohol were significant predictive variables for retention.
The present review did not identify sufficient evidence to assess the effectiveness of SROM for opioid maintenance because only three studies meeting our inclusion criteria have been identified. Two studies suggested a possible reduction of opioid use in people taking SROM. In another study, the use of SROM was associated with fewer depressive symptoms. Retention in treatment was not significantly different among compared interventions while the adverse effects were more frequent with the people given SROM.