To improve the chances that hard-core heroin addicts will stick with their treatment for opioid dependence and forgo the use of illicit drugs, they should take … heroin.

That’s the controversial conclusion of a study being published in Thursday’s edition of the New England Journal of Medicine.

The study focused on addicts who took heroin for at least five years and had already failed two attempts at treatment. One of those attempts had to involve methadone, which helps manage heroin cravings and blocks the drug’s euphoric effects.

The goal wasn’t necessarily to get study participants to stop using heroin altogether, but to turn their addiction into a manageable fact of life instead of a source of high-risk, illegal and/or anti-social behavior.

Canadian researchers randomly assigned 115 addicts in Vancouver and Montreal to receive diacetylmorphine – the active ingredient in heroin – and 111 others to a control group that got standard methadone treatment. Those who took diacetylmorphine injected themselves up to three times a day in treatment clinics with medical supervision. Then they had to remain in the clinic for 30 minutes so they could be monitored for overdoses, seizures and other serious problems.

Overall, the addicts who took diacetylmorphine did better than the ones who took methadone.

After one year, 88% of those in the diacetylmorphine group were still in treatment, compared with 54% in the methadone group. They were also more likely to curb their illegal behavior – including use of illicit drugs – by a margin of 67% to 48%.

Patients treated with diacetylmorphine also saw bigger reductions in their illicit heroin use. They had taken the drug for an average of 26.6 days in the month before the study started, and that number fell to 5.3 days by the end of the study. In the methadone group, illicit heroin use fell from an average of 27.4 days per month to 12.0 days per month during the course of the study.

The researchers also reported that addicts who were treated with diacetylmorphine “had greater improvements with respect to medical and psychiatric status, economic status, employment situation, and family and social relations,” according to the study.

One patient from the methadone group died of an opioid overdose during the 12-month trial. But overall, serious adverse events were more than 2½ times more common among the diacetylemorphine group. Sixteen of those participants experienced a life-threatening seizure or overdose; all received prompt treatment at their clinic and recovered.

The researchers emphasized that most heroin addicts should continue to be treated with methadone. But when methadone doesn’t cut it, they concluded, “prescribed, supervised use of diacetylmorphine appears to be a safe and effective adjuctive treatment for this severely affected population of patients who would otherwise remain outside the health care system.”

That advice may sound radical, but it has already been followed in several European countries. Switzerland, the Netherlands and Great Britain currently treat some heroin addicts with diacetylmorphine, according to an editorial accompanying the study.

In the United States, only methadone has the imprimatur of a “medical” drug, writes Virginia Berridge of the London School of Hygiene and Tropical Medicine at the University of London. That bias may help explain why the Canadian researchers were unable to collaborate with their colleagues south of the border. Perhaps, Berridge speculates, the Canadian results will have more influence on American policymakers since the study was practically “homegrown.”

-- Karen Kaplan

Photo: Methadone helps many heroin users stay off the drug, but it’s not powerful enough for all addicts. Credit: Los Angeles Times