To investigate changes in health-related patient-reported outcome measures (PROMs) and adverse events in patients prescribed cannabis-based medicinal products (CBMPs) for multiple sclerosis (MS).

MS is an autoimmune condition of the central nervous system characterised by several motor, sensory, autonomic and psychiatric symptoms. Despite treatment, many patients continue to experience substantial functional impairment. Existing literature has demonstrated CBMPs having broad therapeutic effects. However, there is a paucity of long-term studies assessing their use in MS.

This observational case series included patients with MS enrolled on the United Kingdom Medical Cannabis Registry. Changes in PROMs (MS Quality of Life-54 (MSQOL-54), Generalised Anxiety Disorder-7 (GAD-7), Single-Item Sleep Quality Scale (SQS) and EQ-5D-5L) were investigated from baseline up to 24 months. All reported adverse events were graded by severity.

Of the 203 patients included, 164 (80.79%) were current or previous cannabis users, with a median lifetime cannabis consumption of 5.00 [2.00-20.00] gram years. At 24 months, the median cannabidiol and (−)-trans-Δ⁹-tetrahydrocannabinol dose was 31.00[16.50-65.88]mg/day and 148.50[33.00-253.25]mg/day, respectively. Improvements in eight MSQOL-54 domains (change in health, energy, health distress, pain, physical function, physical role limitations, mental health composite, physical health composite), SQS score and EQ-5D-5L index value were seen at all follow-up times compared to baseline (p<0.050). Twenty-six patients (12.81%) reported adverse events, with fatigue (n=27, 13.30%), spasticity (n=17, 8.37%) and generalised muscle weakness (n=16, 7.88%) being the most commonly reported.

CBMP treatment up to 24 months was associated with improvements in many MS symptoms, sleep and health-related quality of life. Future studies should aim to investigate causality through randomised controlled trials and further assess CBMP treatment in cannabis naive populations.