Fixed or Self-Titrated Dosages of Sativex on Cannabis Users

This will be a one year pilot/feasibility study, assessing the effects of fixed or self-titrated dosages of SATIVEX® (Δ9-tetrahydrocannabinol /cannabidiol combination in a buccal spray) on withdrawal from cannabis and craving among cannabis dependent subjects. Subjects in this study will undergo an 8-week double-blind, placebo-controlled trial. Subjects will be regular cannabis-users who are not currently seeking treatment for cannabis dependence. Subjects will participate in each of 8 conditions, lasting 5 weekdays each (an ABACADAE study design); four smoke as usual conditions (SAU) and four cannabis abstinence conditions. During each abstinence condition (B, C, D, E conditions), subjects will be allocated to one condition including self-titration of placebo, fixed dose of placebo, self-titration of SATIVEX (up to a max of 40 sprays per day, equal to 108mg THC) or fixed dose of SATIVEX (40 sprays per day). Each medication phase will be followed by a washout period where individuals will be requested to smoke cannabis as usual (A condition). The experimental conditions will be: type of SATIVEX® spray used (active vs placebo), and titration regimen (fixed or self-titrated). This pilot study will allow us to demonstrate the feasibility of our approach and to determine the sample size to use secondarily for a larger study. Our ultimate goal is to determine optimal conditions to use for a subsequent randomized controlled trial assessing the efficacy of SATIVEX® in treatment of Cannabis dependence among treatment-seeking subjects.