The Effect of Cannabis-Based Medicine on Neuropathic Pain and Spasticity in Patients with Multiple Sclerosis and Spinal Cord Injury: Study Protocol of a National Multicenter Double-Blinded, Placebo-Controlled Trial

Disease or acquired damage to the central nervous system frequently causes disabling spasticity and central neuropathic pain (NP), both of which are frequent in multiple sclerosis (MS) and spinal cord injury (SCI). Patients with MS and SCI often request treatment with cannabis-based medicine (CBM). However, knowledge about effects, side effects, choice of active cannabinoids (Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD) alone or in combination), and doses of CBM remains limited. Using a double-blind, parallel design in a national multicenter cohort, this study examines the effect of CBM on spasticity and NP. Patients are randomized to treatment with capsules containing either THC, CBD, THC and CBD, or placebo. Primary endpoints are patient-reported pain and spasticity on a numerical rating scale. Other endpoints include quality of life and sleep, depression and anxiety, and relief of pain and spasticity. Side-effects of CBM are described. In a sub-study, the pharmacodynamics (PD) and pharmacokinetics (PK) of oral capsule CBM are examined. We expect that the study will contribute to the literature by providing information on the effects and side-effects of CBD, THC, and the combination of the two for central neuropathic pain and spasticity. Furthermore, we will describe the PD/PK of THC and CBD in a patient population.