A Phase 2B, 8-Week, Randomized, Double-Blind, Placebo-Controlled, Parallel Group Study to Evaluate the Efficacy, Safety and Tolerability of the Fatty Acid Amide Hydrolase (FAAH) Inhibitor PF-04457845 in Adults with DSM-5 Current Cannabis Use Disorder (CUD)

The efficacy, safety and tolerability of the FAAH Inhibitor PF-0447845 in reducing cannabis use will be studied in a 4-site randomized, double-blind, placebo-controlled, parallel-group, outpatient clinical trial comparing PF-04457845 (4mg) and placebo in DSM-5 CUD individuals. Participants will be randomized in a 1:1 ratio to either PF-04457845 or placebo using random block sizes of 2 and 4, stratified by site and degree of cannabis use. Participants will receive motivational interviewing for 2 weeks before being randomized to receive study medication to make a quit attempt within the first week of treatment. Participants will receive active or placebo PF-04457845 for 8 weeks during which time they will be evaluated weekly in face to face visits. In addition, daily assessment of adherence to study medication and cannabinoid use will be conducted daily by cellphone. Measures of cannabinoid exposure (self-reported and urine toxicology), and problems related to the use of cannabis, will be assessed.

Inclusion Criteria:

1. Ages 18-60 years, inclusive.
2. Male or Female.
3. Individuals with DSM-V criteria for Cannabis Use Disorder .
4. Positive for urinary THC-COOH at both screening visits.
5. Must express a willingness at screening to set a date within the first week of randomization to attempt to quit using cannabis.

Exclusion Criteria:

1. Clinically significant unstable medical disorders (as determined by the site investigator).
2. Laboratory tests with clinically significant abnormalities (as determined by the site investigator)
3. Pregnancy by history and or laboratory confirmation (serum HCG).
4. Lactation.
5. Physiological dependence on another substance.

The adverse events reported were collected throughout the treatment phase of the study (randomization to the end of week 8; i.e. the beginning of the treatment phase of the study through the end of the treatment phase of the study).