The Separate and Combined Effects of Vivitrol and Opiate Abstinence Reinforcement in the Treatment of Opioid Dependence

Injection heroin use is a chronic problem that fuels the transmission of HIV/AIDS through
risky injection behaviors. Methadone and buprenorphine can reduce heroin use and risky
injection behavior; however, they have abuse potential, produce physical dependence, can
produce lethal overdose, are highly regulated, and some patients simply do not want agonist
treatment. Opiate detoxifications can serve as an alternative to agonist treatment, but many
injection drug users relapse to heroin use and resume risky injection behaviors after
detoxification. Vivitrol®, an extended release formulation of naltrexone, was recently
approved by the FDA for the treatment of opioid dependence, but its clinical utility is
uncertain given the reluctance of many opioid-dependent adults to maintain its long-term use,
and the fact that some patients continue to use opiates while under naltrexone blockade. The
investigators research in the first period of this grant showed that employment-based
reinforcement can be highly effective in promoting long-term adherence to Vivitrol®.
Employment-based reinforcement may be ideally suited to address the limitations of extended
release naltrexone by capitalizing on its potential to simultaneously reinforce naltrexone
adherence and opiate abstinence. This grant will evaluate the effectiveness of
employment-based reinforcement to simultaneously promote high rates of Vivitrol® adherence
and increase opiate abstinence. After an opioid detoxification and induction onto oral
naltrexone, participants will be invited to attend the Therapeutic Workplace for 24 weeks
(where they can work and earn wages) and will be randomly assigned to one of four groups that
will differ in whether they receive Vivitrol®, employment-based opiate abstinence
reinforcement, both or neither. Participants in Vivitrol® conditions will be required to take
scheduled injections to work and earn wages. Participants exposed to opiate abstinence
reinforcement will receive a temporary decrease in their workplace pay if they fail to
provide an opiate-free urine sample. The study will assess the effects of the interventions
on weekly opiate urinalysis results, and on measures of injection drug use and cocaine use.
If this study shows that the combined use of Vivitrol® and employment-based reinforcement of
adherence and opiate abstinence is effective in maintaining long-term opiate abstinence, this
model of employment-based addiction pharmacotherapy could be integrated into community
workplaces to disseminate the effective use of Vivitrol®; it could be used to enhance the
utility of other new antagonist-like addiction medications; and it could provide an effective
means of reducing injection drug use in individuals who persist in injecting heroin and
exposing themselves and others to the risk of acquiring or transmitting HIV infection due to
their continued injection drug use and risky injection behaviors.

Inclusion Criteria:

1. meet the DSM-IV criteria for opioid dependence,

2. report using heroin at least 21 of the last 30 days while living in the community,

3. are unemployed,

4. are 18-65 years old,

5. are medically approved for naltrexone,

6. live in or near Baltimore, MD.

Exclusion Criteria:

1. have current DSM-IV major Axis I disorders

2. have current suicidal or homicidal ideation

3. express interest in methadone treatment

4. are required to use opioids for medical purposes

5. earned over $200 in taxable income over the previous 30 days while living in the
community

6. have physical limitations that prevent them from using a keyboard

7. are pregnant or breastfeeding

8. have serum aminotransferase levels over three times normal

9. have known intolerance and/or hypersensitivity to naltrexone, carboxymethylcellulose,
or poly (lactide-co-glycolide) (PLG) or any other components of the diluents;

10. are participating in any other clinical study.