Buprenorphine versus methadone maintenance therapy: a randomized double-blind trial with 405 opioid-dependent patients

Aims To assess the efficacy of buprenorphine compared with methadone maintenance therapy for opioid dependence in a large sample using a flexible dosing regime and the marketed buprenorphine tablet. Design Patients were randomized to receive buprenorphine or methadone over a 13‐week treatment period in a double‐blind, double‐dummy trial. Setting Three methadone clinics in Australia. Participants Four hundred and five opioid‐dependent patients seeking treatment. Intervention Patients received buprenorphine or methadone as indicated clinically using a flexible dosage regime. During weeks 1–6, patients were dosed daily. From weeks 7–13, buprenorphine patients received double their week 6 dose on alternate days. Measurements Retention in treatment, and illicit opioid use as determined by urinalysis. Self‐reported drug use, psychological functioning, HIV‐risk behaviour, general health and subjective ratings were secondary outcomes. Findings Intention‐to‐treat analyses revealed no significant difference in completion rates at 13 weeks. Methadone was superior to buprenorphine in time to termination over the 13‐week period (Wald χ² = 4.371, df = 1, P = 0.037), but not separately for the single‐day or alternate‐day dosing phases. There were no significant between‐group differences in morphine‐positive urines, or in self‐reported heroin or other illicit drug use. The majority (85%) of the buprenorphine patients transferred to alternate‐day dosing were maintained in alternate‐day dosing. Conclusions Buprenorphine did not differ from methadone in its ability to suppress heroin use, but retained approximately 10% fewer patients. This poorer retention was due possibly to too‐slow induction onto buprenorphine. For the majority of patients, buprenorphine can be administered on alternate days.