CBD and multiple sclerosis: what the research establishes

INSERM indicates that around 110,000 people are affected in France, with 4,000 to 6,000 new cases per year, one man for every three women in the relapsing-remitting form, and an onset around age 30 on average. It is the leading cause of severe non-traumatic disability in young adults.

Spasticity is a frequent complication of the disease. Its management belongs to a neurologist, and personal questions should be addressed to one.

The product behind the favourable data is called nabiximols, marketed under the name Sativex. It is not cannabidiol: it is a medicine, each spray of which delivers 2.7 mg of delta-9-THC and 2.5 mg of cannabidiol. It therefore contains THC, and it is classified as a narcotic.

Its marketing authorisation was granted in France on 8 January 2014. Its indication covers symptoms linked to moderate to severe spasticity due to multiple sclerosis, in adults who have not responded sufficiently to other antispastic treatments, as an add-on and not a replacement.

A decisive fact many articles omit: this medicine is not marketed in France. A government answer to a written question, published on 28 February 2023, confirms that it remains unavailable despite its authorisation in seventeen other European countries, the price negotiations having failed and the manufacturer having withdrawn its reimbursement application. Around 5,000 French patients could be concerned.

The opinion of the Transparency Committee of the Haute Autorité de santé, issued on 22 October 2014, is severe and deserves to be quoted precisely. The medical benefit is judged low, and the improvement in medical benefit non-existent, that is, level V. The committee notes a modest balance between efficacy and adverse effects, and considers that the impact on quality of life is not demonstrated.

The detail of the pivotal trials sheds light on that judgement. The first showed a difference of 0.52 points on a spasticity scale rated from 0 to 10, below the gap set out in the protocol. The second, conducted in 337 patients, was negative on its primary endpoint. The third rested on an enriched design: of 572 patients who received the product open-label, only the 241 who were already responders were randomised.

A technical point runs through all three trials: the Ashworth scale, rated by the clinician, was not significant in any of them. Only the patient-reported scales moved. The committee estimated the benefit clinically relevant in around 10 to 20% of insufficiently relieved patients.

The Cochrane review published in May 2022 on cannabinoids in multiple sclerosis brings together 25 randomised trials and 3,763 participants. On patient-reported spasticity, nabiximols probably increases the number of people reporting an important reduction, with an odds ratio of 2.51 and a 95% confidence interval of 1.56 to 4.04, at a moderate level of certainty.

On health-related quality of life, by contrast, the standardised mean difference is minus 0.08, confidence interval minus 0.17 to 0.02: no effect. The risks are documented, with an odds ratio of 2.41 for withdrawals linked to an adverse event, 2.61 for nervous system disorders and 1.94 for psychiatric disorders.

The essential limitation is this: the 25 trials concern THC or a THC-CBD combination. None tests cannabidiol alone.

It was published in 2025 in Naunyn Schmiedeberg's Archives of Pharmacology. Conducted in Iran in 49 patients receiving up to 80 mg of purified cannabidiol per day for one month, it concludes that cannabidiol does not significantly reduce the severity of spasticity. Differences appear on two secondary endpoints, timed walking and pain.

Caution is required: a single-centre trial, 49 participants, four weeks, and positive secondary endpoints while the stated target was negative. This work formulates a hypothesis; it does not demonstrate one.

On disease progression, the CUPID trial published in 2013 in The Lancet Neurology followed 498 patients for three years on oral THC. The hazard ratio for disability progression was 0.92, confidence interval 0.68 to 1.23, p-value 0.57. The authors conclude that there is no overall effect on progression.

On spasticity itself, a phase III trial completed in 2022 in 68 patients, comparing nabiximols with placebo on a clinician-rated measure, did not meet its primary endpoint: a difference of 0.04, confidence interval minus 0.16 to 0.23, p-value 0.7152.

Cannabis-based medicines are emerging from the experimentation phase. The Haute Autorité de santé was referred the matter in March 2025 and retains five indications, including the painful spasticity of multiple sclerosis, smoked forms being excluded. Its final opinion was awaited and we had not verified its publication at the date of this article. Our articles on medical cannabis in France and on the sale of therapeutic cannabis follow this file.

One distinction to finish: cannabidiol sold freely is not a medicine, and the only cannabidiol-based specialty authorised in the European Union concerns rare epilepsies. Our articles on clinical studies and on the differences between CBD and THC clarify these boundaries.

Does shop-bought CBD act on spasticity?

No data allow that claim. The 2022 Cochrane review, which brings together 25 trials, contains no trial of cannabidiol alone, and the only trial of purified cannabidiol published since, in 49 patients, concludes that there is no significant reduction in spasticity.

Is Sativex available in France?

No. It has held a marketing authorisation since 8 January 2014, but it has never been marketed, the price negotiations having failed. A government answer of February 2023 confirms this unavailability, while it is authorised in seventeen other European countries.

Do cannabinoids slow the progression of the disease?

No, according to the available data. The CUPID trial, conducted in 498 patients over three years, showed no overall effect on disability progression, with a hazard ratio of 0.92 and a p-value of 0.57. No trial supports a disease-modifying role.