Safety and Efficacy of a FAAH-Inhibitor to Treat Cannabis Withdrawal

FAAH-Inhibitor for Cannabis Dependence

Cannabis dependence is associated with changes in the brain's cannabinoid system. When cannabis dependent individuals try to quit using cannabis, some of them experience problems that make it difficult for them to achieve and maintain abstinence. Therefore, reducing the problems related to quitting cannabis may facilitate abstinence. One way to do this is by harnessing the brain's capacity to make its own cannabis-like substances - endocannabinoids. One of the main endocannabinoids is anandamide. The study is based on the hypothesis that the problems related to quitting cannabis use will be reduced by increasing the brain levels of anandamide. Furthermore, by reducing the problems related to quitting cannabis, people will be less likely to relapse. Brain anandamide levels will be increased by blocking the breakdown of anandamide using a fatty acid amide hydrolase inhibitor (FAAH-I). The effects of a novel FAAH-I cannabis withdrawal and relapse in cannabis dependent subjects will be studied in a double-blind, randomized, controlled, proof-of-concept study. Cannabis-dependent subjects will receive placebo or the FAAH-inhibitor PF-04457845 in a 2:1 randomization. The trial consists of a 1 week inpatient stay to achieve abstinence, a 3 week outpatient treatment phase. Cannabis withdrawal will be measured during the inpatient phase. Cannabis use and urinary THC-COOH levels will be measured during the entire study. The treatment phase will be followed by a safety follow up phase of 8 weeks.

Inclusion Criteria:

1. Male
2. Ages 18-55 (inclusive)
3. Cannabis Dependence

Exclusion Criteria:

1. Allergies or intolerance to FAAH-Inhibitors
2. Current significant medical or other comorbidities