106 patients with resistant multiple sclerosis who had demonstrated adequate treatment response to Sativex (tetrahydrocannabinol and cannabidiol oromucosal spray) treatment in a 4-week trial phase were randomized to Sativex or placebo for 12 weeks after 1-4 week washout from the trial phase. The purpose of the study was to determine if tetrahydrocannabinol and cannabidiol oromucosal spray (THC:CBD group) significantly improve spasticity, pain, spasm frequency and severity, sleep disruption quality of life, and functional performance compared to placebo. The modified Ashworth scale, and Expanded Disability Status Scale were also used as outcome measures. Results indicate that THC:CBD treatment significantly improved spasticity, pain, sleep disruption, and spasm severity scores compared to placebo with a significantly higher proportion of responders to treatment, defined as minimum 30% improvement on a 0-10 spasticity numeric rating scale.