THC:CBD spray and MS spasticity symptoms: data from latest studies.

New clinical experience with 9-delta-tetrahydocannabinol (THC) and cannabidiol (CBD) oromucosal spray (Sativex®) involving more than an additional 1,000 patients with MS spasticity (approximately 150 in clinical studies and 900 in post-marketing surveillance studies) have become available in 2013 and are reviewed. A randomized, placebo controlled long-term follow-up clinical trial with THC:CBD spray versus placebo demonstrated that it was not associated with cognitive decline, depression or significant mood changes after 12 months of treatment. Furthermore, in a prospective observational pilot study involving 33 patients (60% female) aged 33-68 years and a mean disease duration of 6.6 years, THC:CBD oromucosal spray did not adversely influence standard driving ability in patients with moderate to severe MS spasticity. Other new long term observational data about the use of THC:CBD oromucosal spray in clinical practice are available from patient registries in the UK, Germany and Spain. Findings to date reinforce the efficacy and safety observed in Phase III clinical trials. It is of interest that in practice average dosages used by patients tended to be lower than those reported in clinical studies (5-6.4 vs. >8 sprays/day), and effectiveness was maintained in the majority of patients. Importantly, no additional safety concerns were identified in the registry studies which included findings from patients who have been treated for prolonged periods (in the German/UK registry 45% of patients had >2 years exposure). Thus, these new data support a positive benefit-risk relationship for THC:CBD oromucosal spray during longer-term use.