Sativex® as Add-on therapy Vs. further optimized first-line ANTispastics (SAVANT) in resistant multiple sclerosis spasticity: a double-blind, placebo-controlled randomised clinical trial.

Purpose/aim: To evaluate the efficacy of tetrahydrocannabinol [THC]:cannabidiol [CBD] oromucosal spray (Sativex®) as add-on therapy to optimized standard antispasticity treatment in patients with moderate to severe multiple sclerosis (MS) spasticity.

METHODS:

Sativex as Add-on therapy Vs. further optimized first-line ANTispastics (SAVANT) was a two-phase trial. In Phase A, eligible patients received add-on THC:CBD spray for 4 weeks to identify initial responders (≥ 20% improvement from baseline in spasticity 0-10 numerical rating scale [NRS] score). Following washout, eligible initial responders were randomised to receive THC:CBD spray or placebo for 12 weeks (double-blinded, Phase B). Optimization of underlying antispasticity medications was permitted in both groups across all study periods.

RESULTS:

Of 191 patients who entered Phase A, 106 were randomised in Phase B to receive add-on THC:CBD spray (n = 53) or placebo (n = 53). The proportion of clinically-relevant responders after 12 weeks (≥ 30% NRS improvement; primary efficacy endpoint) was significantly greater with THC:CBD spray than placebo (77.4 vs 32.1%; P < 0.0001). Compared with placebo, THC:CBD spray also significantly improved key secondary endpoints: changes in mean spasticity NRS (P < 0.0001), mean pain NRS (P = 0.0013), and mean modified Ashworth’s scale (P = 0.0007) scores from Phase B baseline to week 12. Adverse events, when present, were mild/moderate and without new safety concerns.

CONCLUSIONS:

Add-on THC:CBD oromucosal spray provided better and clinically relevant improvement of resistant MS spasticity compared with adjusting first-line antispasticity medication alone.