Wood/Korthuis—Vivitrol study

Rick Cluff: Local doctors who work in addiction services are getting $3 million in additional funding from the province. Those funds will go towards the clinical trial of a drug called Vivitrol, which is an injection that blocks the effects of alcohol or heroin. Now, this study comes at a time when there are many criticisms of current heroin addiction treatments, from changes to the methadone program to the Conservative government's opposition to prescribed heroin. Dr Evan Wood says the study is a great fit, particularly for Vancouver.

Evan Wood: Normally a patient who is coming off of heroin, we know that their likelihood of relapse to heroin use after detoxification is about 80%, and if someone gets a Vivitrol injection, even if they relapse to heroin injection, it'll have no effect upon them.

Cluff: Now, for more on Vivitrol, on the line now is Dr Todd Korthuis, who is an addiction specialist based in Oregon who has studied this drug extensively. We have reached him this morning at the airport.

Doctor, good morning.

Todd Korthuis: Good morning.

Cluff: What's the difference between Vivitrol versus other treatments for heroin addiction like methadone?

Korthuis: Extended release naltrexone is interesting in that it blocks opioid receptors instead of activating them, and so someone who is taking extended release naltrexone experiences no effects if they use heroin or other medicines like it.

Cluff: What are the benefits to the patient, then?

Korthuis: For the patients there are two big benefits. First of all, it decreases cravings, so people feel less like using, and second of all, it's a one-a-month injection as opposed to most other treatments like methadone or buprenorphine that have to taken daily.

Cluff: Once a month? It would last that long, then?

Korthuis: That's right, yes, and because it's also integrated into regular health care, any primary care doctor can provide this. It's just like going and getting any other medication once a month.

Cluff: Would it work together with other forms of treatment?

Korthuis: Well, any form of treatment for drug or alcohol dependence should always be accompanied by some sort of psychosocial counselling and group therapy and other supports, but extended use naltrexone can't be combined with things like methadone and buprenorphine because those also activate the opioid receptors.

Cluff: How common is Vivitrol, or as you call it, extended release naltrexone, in the United States?

Korthuis: It's just starting to be prescribed more widely. It's been available for several years, but people are starting to use it more now.

Cluff: Why the hesitancy? If it's been there for a number of years, why are they just starting to use it now?

Korthuis: That's a great question. I think part of the problem is that there's somewhat limited experience using it, and one of the purposes of our study is to expand, experience and learn better what patients prefer and providers prefer in terms of treatment of opiate dependence.

Cluff: Now, you oversee the CHOICES study in which Vancouver was involved. They are part of this study. What was the goal of the study?

Korthuis: The goal of the study is exactly what we were just talking about. It's to test the feasibility of doing this in regular practice. We're focusing on HIV clinics and seeing what the acceptability is among patients and also among the doctors in those clinics for providing extended release naltrexone.

Cluff: Yet the drug is not available here in Canada.

Korthuis: Yes, we're hoping that that will change during the course of the study, but this provides data that Health Canada and other policy makers can use about the acceptability and feasibility of doing this in Canada.

Cluff: As you might know, the federal Conservative government of this country has a philosophy opposed to treatments like prescribed heroin, as we saw in the NAOMI studies, or supervised sites. They're against that as well. Do you think a treatment like this, extended use naltrexone, or Vivitrol, would be easier to accept for those who are normally opposed?

Korthuis: Well, I think the decision about acceptance really resides with the patient and the provider. What we're trying to do with the CHOICES study is to expand the range of treatment options that patients and their treatment providers have for effective treatment. In the case of extended release naltrexone, this means treatment with a non-narcotic medicine, which is very attractive to many patients and providers.

Click here to listen to the full interview (August 12, 2014, skip to 1:52:16)