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

Abstract

Aims: Evaluation of the efficacy and safety of slow-release oral morphine (SROM) compared with methadone for detoxification from methadone and SROM maintenance treatment.

Design: Randomized, double-blind, double-dummy, comparative multi-centre study with parallel groups.

Setting: Three psychiatric hospitals in Austria specializing in in-patient detoxification.

Participants: Male and female opioid dependents (age > 18 years) willing to undergo detoxification from maintenance therapy in order to reach abstinence.

Interventions: Abstinence was reached from maintenance treatment by tapered dose reduction of either SROM or methadone over a period of 16 days.

Measurements: 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.

Findings: 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.

Conclusions: Detoxification from maintenance treatment with tapered dose reduction of SROM is non-inferior to methadone.

Figure 1

Dose reduction scheme of slow-release oral morphine (SROM) and methadone (level 1 , level 2 ▴, level 3 ×, level 4 ♦)

Figure 2

Schematic representation of patient flow throughout the study (n = 208)

Figure 3

Kaplan–Meier plot of patient discontinuations during the study [slow-release oral morphine (SROM) —, methadone - - -]

Figure 4

Craving for opiates, alcohol, cocaine and cannabis [self-assessment via visual analogue scale (VAS) 0 = no craving, 100 = most intense craving][slow-release oral morphine (SROM) ▴, methadone ♦]