Heroin Treatment May Help Difficult-to-Treat Opioid Addicts

A Canadian study shows that heroin maintenance keeps some patients in drug treatment longer than methadone therapy and reduces illegal behaviors in certain difficult-to-treat patients with chronic relapsing opioid addiction. Meanwhile, clinicians and other addiction experts continue to debate the efficacy of various addiction treatment approaches.

The new study, known as the North American Opiate Medication Initiative (NAOMI), was conducted by Eugenia Oviedo-Joekes, Ph.D., and colleagues at the University of British Columbia and the Université de Montréal and published in the August 20 New England Journal of Medicine. It was funded by the Canadian Institutes of Health Research, Canada Foundation for Innovation, Canada Research Chairs Program, the universities of British Columbia and Montreal, and provincial government agencies.

From 2005 to 2008 in Montreal and Vancouver, patients who had DSM-IV-diagnosed opioid dependence, injected heroin daily, and had failed at least two previous treatments including at least one methadone treatment were recruited for the study. Participants were randomized to receive either oral methadone (n=111) or diacetylmorphine injection (n=115) treatment for 12 months in an open-label design. Diacetylmorphine is the active ingredient in heroin and was self-administered by participants under medical supervision at the study clinics.

Nearly 88 percent of heroin-treated patients remained in the treatment at the end of one year, statistically significantly higher than the 54 percent retention rate for the methadone-treated patients.

In addition, 67 percent of heroin-treated patients met the criteria for responders in terms of reduced illicit-drug use or illegal activities, compared with 48 percent of methadone-treated patients, also a statistically significant difference. Patients were considered responders if they had at least a 20 percent reduction from baseline in either the illicit-drug use or the illegal-activity subscales of the European Addiction Severity Index.

The study protocol allowed participants to self-administer diacetylmorphine at a maximum of three times a day, with a dose of no more than 1,000 mg/day. The actual dose used by participants averaged 392 mg/day. The mean dose of methadone given in the study was 96 mg/day.

Diacetylmorphine use was associated with more serious adverse events, including overdose in 10 patients, which required immediate treatment with naloxone, and seizure in six patients.

The findings from this study were not unexpected and were similar to those from several studies conducted in Germany, Switzerland, the Netherlands, and Spain since the 1990s on heroin-maintenance treatment in chronically addicted patients. The most recent was a German study by Christian Haasen, M.D., and colleagues at the University Medical Center Eppendorf in Hamburg and published in the July 2007 British Journal of Psychiatry.

In these studies patients who received heroin-maintenance treatment in a supervised environment were found to do better than patients who received methadone on a number of outcome indicators such as improvement in physical health and decreased criminal behaviors. The Canadian study, however, is the first heroin study published in a major U.S. medical journal.

These studies do not demonstrate that heroin-maintenance treatment is more efficacious than methadone, Charles O'Brien, M.D., Ph.D., told Psychiatric News. Rather, the findings are limited to a small segment of opioid-addicted patients. “The [heroin-maintenance] approach represents a second-class therapy for people who refuse to get methadone treatment,” he said.

O'Brien is the Kenneth Appel Professor of Psychiatry at the University of Pennsylvania and chair of the DSM-V work group on areas related to addiction psychiatry. He also served as a consultant for the heroin-maintenance study in the Netherlands.

Commenting on the NAOMI study, O'Brien noted that the research protocol gave participants the option of a maximum of three injections of heroin a day. Maintaining opioid addicts on heroin as the Canadian researchers did “is a way of harm reduction, but [patients] were not motivated to change their lives,” he said. “They get high three times a day, which interferes with normal life.... Methadone or buprenorphine treatment can enable rehabilitation.”

Heroin maintenance is also prohibitively expensive, O'Brien emphasized. It would be unwise to adopt it widely in the U.S. health care context, where treatments for addiction, such as methadone and buprenorphine, are poorly funded in the first place. “We don't even have enough money for methadone therapy. We should put the funds into making methadone and buprenorphine treatment and proper counseling available to more people with opioid dependence, which will make a far bigger difference.”

Trends in opioid addiction treatment “often owe more to the politics of the situation” and to “professional factors” than to research evidence, Virginia Berridge, Ph.D., a professor in history and public health policy analysis at the London School of Hygiene and Tropical Medicine, University of London, wrote in an accompanying editorial. She pointed out that in countries where the opioid-addiction studies were conducted, Switzerland and the Netherlands have chosen to adopt heroin maintenance as a treatment option, but Germany and Spain have not.

An abstract of “Diacetylmorphine Versus Methadone for the Treatment of Opioid Addiction” is posted at<content.nejm.org/cgi/content/abstract/361/8/777>. An abstract of “Heroin-Assisted Treatment for Opioid Dependence: Randomised Controlled Trial” is posted at<bjp.rcpsych.org/cgi/content/abstract/191/1/55>.▪