Is there a need for heroin substitution treatment in Vancouver's Downtown Eastside?

The North American Opiate Medication Initiative (NAOMI) was a randomized controlled trial conducted in Vancouver and Montreal comparing heroin substitution treatment (HST) to methadone treatment (MT) for heroin addicts. The HST group had a higher treatment retention rate and lower illicit heroin use than the MT group. Despite the rigour with which the study was designed, systematic flaws have affected the interpretation of the results. In the MT arm, the dose was titrated slowly, contributing to the high early dropout rate. The mean maintenance dose was suboptimal. The investigators did not calculate on-treatment retention rates; by the end of the trial, more subjects were on MT than HST. Life-threatening events were more common in the HST than the MT group. Overall, the only clear advantage of HST over MT was its greater initial treatment attractiveness, resulting in more early drop-outs in the MT group. HST is intended for treatment-refractory addicts who have no other option but to use street heroin. Yet for most NAOMI subjects, the safest and most cost-effective approach is comprehensive MT or buprenorphine with optimal dosing, flexible program policies, and the provision of integrated primary care and social services. These proven strategies, currently lacking in Vancouver's Downtown Eastside, should be implemented before diverting already insufficient resources to HST, given its risks, cost and uncertain efficacy.