A Study of The Abuse Liability Potential of RO4917838 in Recreational Drug Users

Study Overview
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Brief Summary
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This randomized, placebo- and active-controlled, crossover study will evaluate the abuse liability potential of RO4917838 in recreational drug users. In a pre-study (Part 1), subjects will receive a single dose of either diazepam or placebo in an inpatient crossover design, with a wash-out period of at least 10 days between treatments. Subjects who are clearly able to distinguish the positive control from placebo will be enrolled in the main study (Part 2) and will be randomized to single oral doses of RO4917838 (3 dose levels), diazepam and placebo in a double-blind, double-dummy inpatient crossover design. Washout-periods between the 5 treatment periods in Part 2 will be at least 10 days.

Official Title
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Human Abuse Liability Study in Recreational Drug Users to Investigate the Abuse Liability Potential of RO4917838

Conditions
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Healthy Volunteer

Intervention / Treatment
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* Drug: Placebo
* Drug: RO4917838
* Drug: diazepam


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy male or female volunteers, 18 to 55 years of age inclusive Recreational drug abuse experience (>/= 10 times lifetime abuse of a CNS depressant, >/= 1 abuse of CNS depressant in the previous 3 months Body mass index (BMI) 18 to 30 kg/m2 inclusive Main study (Part 2): Able to differentiate between diazepam and placebo Exclusion Criteria: History of any significant disease or disorder History or current diagnosis of substance dependence (excluding caffeine and nicotine) Currently seeking or history of participating in treatment for substance-related disorders, including successful completion of such treatment Any confirmed significant allergic reactions against any drug, or multiple allergies in the judgement of the investigator Positive for hepatitis B, hepatitis C or HIV infection Pregnant or lactating women Participation in an investigational drug or device study within the last 30 days prior to Day 1 of the study Confirmed positive drug screening at screening / any Day -1 (allowed positive THC at screening and any Day -1 and positive benzodiazepine at screening only) Positive alcohol breath test at screening / any Day -1 Heavy smoker (> 20 cigarettes, > 8 pipefuls or > 8 cigars per day)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: A<br> | Drug: diazepam<br>* Single dose<br>|
| Placebo Comparator: B<br> | Drug: Placebo<br>* Single dose<br>|
| Experimental: C<br> | Drug: RO4917838<br>* Single doses (3 dose levels)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pharmacodynamics: Abuse potential measured by Visual analogue scales (VAS) |  | approximately 11 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Safety: Incidence of adverse events |  | approximately 11 months | 
| Pharmacokinetics: plasma concentrations of RO4917838 |  | approximately 11 months | 
| Pharmacodynamics: Addiction Research Center Inventory (ARCI) subscales |  | approximately 11 months |