Reinforcing Effects of Intranasal (IN) Buprenorphine Versus Buprenorphine/Naloxone

Phase 3

Completed

Conditions: Heroin Dependence

Interventions: Drug: Intranasal challenge drug

Registration Number: NCT01760473

Lead Sponsor: New York State Psychiatric Institute

Brief Summary: The study is designed to compare the abuse liabilities of intranasal buprenorphine and buprenorphine/naloxone in individuals who are physically dependent on sublingual buprenorphine. The investigators hypothesize that the abuse liability of buprenorphine/naloxone is lower than that of buprenorphine alone.

Detailed Description: Although sublingual buprenorphine is an effective treatment for opioid addiction, the medication itself has abuse liability and, in some countries, has largely replaced heroin as the opioid drug of choice. In response to the reports of diversion and abuse of sublingual (SL) buprenorphine, a potentially less abusable formulation of buprenorphine that contains naloxone is being marketed in several countries. However, the relative abuse liability of buprenorphine alone and the buprenorphine/naloxone combination in buprenorphine-dependent individuals is unclear. Preliminary data from a study funded by Schering-Plough Corporation suggest that the buprenorphine/naloxone combination, when given intravenously (IV), does indeed have less abuse liability than IV buprenorphine in buprenorphine-dependent individuals. In addition to IV abuse of buprenorphine, epidemiological data suggest that buprenorphine is widely abused by the intranasal (IN) route. However, no data exist on the abuse liability of either IN buprenorphine alone or the buprenorphine/naloxone combination. Several studies have shown that naloxone is an effective antagonist of opioid agonist effects when given intravenously, but it is not clear whether naloxone given intranasally is as effective as when it is given by other routes of administration. Some studies have suggested that they are equally effective (Loimer et al., 1994), but others have shown that naloxone given intranasally is less effective (i.e., has a slower onset of effects) than when given by other routes of administration (Kelly et al., 2005). How this may impact on the ability of naloxone to reduce the reinforcing effects of IN buprenorphine is unclear. The primary aim of the current study proposal is to compare the reinforcing effects of IN buprenorphine and buprenorphine/naloxone in IN opioid abusers who are maintained on SL buprenorphine using a study design parallel to that used in our recent studies of the abuse liability of IV buprenorphine and buprenorphine/naloxone. Placebo, heroin, and naloxone will be used as neutral, positive, and negative controls, respectively. Secondary aims are to compare the subjective, performance, and physiological effects of IN buprenorphine and buprenorphine/naloxone. Overall, this study will complement our investigations of IV buprenorphine products by allowing for a complete overview within the same laboratory self-administration model of both the intravenous and intranasal abuse liability of buprenorphine versus buprenorphine/naloxone in individuals maintained on buprenorphine. The primary aim of the study is to compare the reinforcing effects of IN buprenorphine and IN buprenorphine/naloxone in opioid abusers maintained on different doses of sublingual buprenorphine. Secondary aims of the study are to compare the subjective, performance and physiological effects of IN buprenorphine and IN buprenorphine/naloxone. IN-administered placebo (lactose powder), naloxone alone, and heroin alone will be tested as neutral, negative, and positive control conditions, respectively. Participants (N=12 completers) will reside on an inpatient unit (5-South) during a 7 to 8-week study. This research will provide useful information to clinicians treating opioid dependent individuals with buprenorphine, and importantly, will provide information about the abuse potential and effects of buprenorphine on multiple measures of human functioning.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 27

Inclusion Criteria

DSM IV criteria for heroin dependence
No major mood, psychotic, or anxiety disorder
Physically healthy
Able to perform study procedures
21-45 years of age
Normal body weight
Current use of opioids in amounts and/or frequencies that meet or exceed those used in the proposed study (e.g., 1-2 bags of heroin per occasion at least twice per day)
Self-administer IN buprenorphine above placebo levels during the qualification phase (see below)

Exclusion Criteria

DSM IV criteria for dependence on drugs other than opioids, nicotine or caffeine
Participants requesting treatment
Participants on parole or probation
Pregnancy or lactation
Birth, miscarriage or abortion within 6 months
Current or recent history of significant violent behavior
Current major Axis I psychopathology, other than opioid dependence (e.g., mood disorder with functional impairment or suicide risk, schizophrenia), that might interfere with ability to participate in the study
AST or ALT > 3 times the upper limit of normal
Significant suicide risk
Current chronic pain
Sensitivity, allergy, or contraindication to opioids
Current or recent (past 30 days) physical dependence on or treatment with methadone, buprenorphine, or the buprenorphine/naloxone combination

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Bup/Nal 8/8	Intranasal challenge drug	Intranasal challenge drug: 8 mg of Buprenorphine administered intranasally with 8 mg of Naloxone.
Heroin	Intranasal challenge drug	Intranasal challenge drug: 24 mg of heroin administered intranasally.
Naloxone 4 mg	Intranasal challenge drug	Intranasal challenge drug: Intranasal Naloxone 4mg.
Bup/Nal 8/16	Intranasal challenge drug	Intranasal challenge drug: 8 mg of Buprenorphine administered intranasally with 16 mg of Naloxone.
Bup 8	Intranasal challenge drug	Intranasal challenge drug: 8 mg of Buprenorphine administered intranasally.
Placebo	Intranasal challenge drug	Intranasal challenge drug: Intranasal lactose powder.
Bup 16	Intranasal challenge drug	Intranasal challenge drug: 16 mg of Buprenorphine administered intranasally.
Bup/Nal 16/4	Intranasal challenge drug	Intranasal challenge drug: 16 mg of Buprenorphine administered intranasally with 4 mg of Naloxone.
Bup/Nal 8/2	Intranasal challenge drug	Intranasal challenge drug: 8 mg of Buprenorphine administered intranasally with 2 mg of Naloxone.

Primary Outcome Measures

Name	Time	Method
Drug Self-administration	Throughout the testing sessions (approximately 9 weeks).	The maximum number of responses (clicks on a computer mouse) the participant was willing to perform in order to receive a dose of the intranasal challenge drug under investigation.

Secondary Outcome Measures

Name	Time	Method
SOWS	Throughout the testing sessions (approximately 9 weeks).	Subjective opioid withdrawal scale (SOWS) measure (0-64). Greater score indicates more severe withdrawal.