Aims. To evaluate the effectiveness of buprenorphine compared with methadone maintenance therapy in opiate addicts over a treatment period of 24 weeks. Design. Subjects were randomized to receive either buprenorphine or methadone in an open, comparative study. Setting. Subjects were recruited and treated at the drug addiction outpatient clinic at the University of Vienna. Participants. Sixty subjects (19 females and 41 males) who met DSM-IV criteria for opioid dependence and were seeking treatment. Intervention. Subjects received either sublingual buprenorphine (2-mg or 8-mg tablets; maximum daily dose 8 mg) or oral methadone (racemic D 2 / 1 L-methadone; maximum daily dose 80 mg). A stable dose was maintained following the 6-day induction phase. Measurement. Assessment of treatment retention and illicit substance use (opiates, cocaine and benzodiazepines) was made by urinalysis. Findings. The retention rate was signi® cantly better in the methadone maintained group (p , 0.05) but subjects completing the study in the buprenorphine group had signi® cantly lower rates of illicit opiate consumption (p 5 0.04). Conclusion. The results support the superiority of methadone with respect to retention rate. However, they also con® rm previous reports of buprenorphine use as an alternative in maintenance therapy for opiate addiction, suggesting that a speci® c subgroup may be bene® ting from buprenorphine. This is the ® rst comparative trial to use sublingual buprenorphine tablets: previously published comparison studies refer to 30% solutions of buprenorphine in alcohol.

Buprenorphine appears to be well accepted by mother and fetus, and associated with a low incidence of NAS. Further investigation of buprenorphine as a maintenance agent for opioid-dependent pregnant women is needed.

Oral slow-release morphine is as effective as methadone in the treatment of opioid dependency, with comparable safety and tolerability and a greater benefit on patient wellbeing. Greater pharmaceutical diversity represents a modern development in mainstream medicine. Slow-release morphine might represent a future treatment option that will improve long-term outcomes for this target group.

To our knowledge this is the first report detailing the pregnancies of women treated with buprenorphine at the time of conception and investigated in a prospective study. The NAS noted in neonates born to buprenorphine-maintained mothers appears to be less severe than the NAS observed in neonates born to methadone-maintained mothers. These preliminary data indicate that, in our patient cohort, buprenorphine maintenance at the time of conception and during pregnancy did not seem to affect birth outcome measurements such as pregnancy complications, week of delivery, birth weight, length, umbilical pH or neurodevelopmental progress. Future prospective studies with larger study populations are warranted.

Both methadone and morphine are suitable maintenance agents for pregnant opiate addicts. Maintenance agents that result in a less prolonged NAS should be studied in further trials.