Most illicit opioid use is heroin use and it is estimated that there are 12.6 million injecting drug users (IDUs) worldwide. Around 10% of HIV infections are associated with injecting drug use and users are also exposed to a high risk of hepatitis B and C. Treatment of heroin dependence is therefore of high public health relevance.

Both buprenorphine and methadone are effective for the treatment of heroin dependence (1, 2). However, methadone maintenance therapy at appropriate doses is the most effective in retaining patients in treatment and suppressing heroin use (3). Methadone is less costly than buprenorphine. It was reported that the cost of buprenorphine per patient per year varied from US$ 300-600 for the generic product to approximately US$ 1750-3500 as a branded product. Besides conventional randomized controlled trials with abstinence rate as an outcome, there is evidence of effectiveness in various societal effects (such as a reduction in criminality) which should also be taken into consideration.

The Expert Committee noted that the use of methadone reduces seroconversion of HIV/AIDS and interacts with antiretroviral medicines, but that this only affects the serum level of methadone, requiring adjustment to the patient response. The Committee therefore recommended that methadone (and buprenorphine, as being within the same pharmacological class) be added to the complementary list, within a new subsection 24.5 "Medicines used in substance dependence programmes" and a note that these products should only be used within an established support programme.

References

1. Mattick RP, Kimber J, Breen C, Davoli M. Buprenorphine maintenance versus placebo or methadone maintenance for opioid dependence. The Cochrane Database of Systematic Reviews 2003, Issue 2. http://www.cochrane.org/cochrane/revabstr/AB002207.htm,

2. Mattick RP, Breen C, Kimber J, Davoli M. Methadone maintenance therapy versus no opioid replacement therapy for opioid dependence. The Cochrane Database of Systematic Reviews 2003, Issue 2. http://www.cochrane.org/cochrane/revabstr/AB002209.htm.

3. Amato L, Davoli M, Ferri M, Perucci C, Effectiveness of opiate maintenance therapies: an overview of systematic reviews. Cochrane Colloquia, Ottawa 2004 http://www.cochrane.org/colloquia/abstracts/ottawa/P-004.htm.