Dr. Martin Schechter says Vancouver's NAOMI clinic should be re-opened. (CBC News)

A University of B.C. epidemiologist says there is now evidence to support a heroin-assisted addictions therapy clinic in Vancouver.

The North American Opiate Medication Initiative, or NAOMI, study was a Vancouver and Montreal-based clinical trial assessing how patients respond to heroin, methadone and other opiate treatment.

The three-year study treated 251 of the most chronically addicted in both Vancouver and Montreal who have not responded well to other treatment options.

"These people are out in the alleys, injecting heroin of unknown quality and quantity," said Dr. Martin Schechter, the study's principal investigator. "They're committing crimes, they're involved in sex work to pay for that, and they're certainly, in that situation, not going to get better."

The study was funded by an $8.1-million research grant from the Canadian Institutes of Health Research and was approved by Health Canada.

The study's participants received methadone, injected heroin or an opiate known as hydromorphone.

The study found illicit heroin use among participants fell by almost 70 per cent, the proportion of participants involved in illegal activity fell to 36 per cent from 70 per cent, and participants who were once spending on average $1,500 per month on drugs reported spending between $300 and $500 per month by the end of the treatment phase.

Schechter said that is enough evidence to show heroin-assisted therapy is a safe and effective treatment for the chronically addicted, and he wants to reopen the heroin-assisted therapy clinic in Vancouver that was used in the study.

"It could treat 200 of the most severely affected people who, right now, are completely outside of the treatment system," he said. "Rather than having them out on the street, costing society approximately $50,000-$60,000 a year, we can treat them in this type of clinic at $25 per person per day which is far, far less."

However, what surprised researchers most was the effectiveness of hydromorphone, which could be used as an effective substitute for heroin or oral methadone. Of the 25 recipients given the legal opiate, only one was able to correctly identify that he or she wasn't getting heroin.

The findings may not sit well with a tough-on-crime federal government, Schechter said, but politicians ignore this science at their peril.

"If governments are interested in reducing crime, this type of treatment offers them an excellent way to do so," he said.

However, B.C.'s health minister said in a press release it will take time for the provincial government to decide whether to fund a heroin-assisted clinic in Vancouver.

Harm reduction is a priority, George Abbott said, and the government will look carefully at the results of the NAOMI study over the next few weeks before making any decisions about funding.