Combined THC/CBD Extracts for MS Spasticity: What the Clinical Trials Show | Research

The takeaway

A systematic review of six randomized trials found a trend toward reduced spasticity with THC/CBD extracts in MS patients, with significant subjective improvement but no significant changes on objective measures.

Read this if you have MS and are evaluating cannabis-based treatments for spasticity.

Subjective improvement was significant; objective measures showed trends but not significance

What the researchers found

Six randomized controlled trials of combined THC and CBD extracts for MS-related spasticity were systematically reviewed.

A consistent trend of reduced spasticity in treated patients was observed across studies. However, the pattern of results differed between measurement types.

Objective measures of spasticity (clinical scales, physiological tests) showed improvement trends but no statistically significant changes.

Subjective assessments of symptom relief often showed statistically significant improvement.

Adverse events were reported in every study, but combined THC/CBD extracts were generally considered well-tolerated.

Why it matters

The disconnect between subjective and objective spasticity measures raises important questions about what outcomes matter most. Patients may experience meaningful relief even when clinical scales do not detect significant changes.

The numbers in context

Six RCTs were included. All six reported adverse events. Subjective measures often showed significant improvement. Objective measures showed trends but no significant changes.

How the study worked

Systematic review of MEDLINE/PubMed, Ovid, and CENTRAL databases for randomized controlled trials using combined THC and CBD extracts with pre- and post-treatment spasticity assessments. Six studies met inclusion criteria.

What this study cannot tell us

Only six studies met inclusion criteria. Variation in outcome measures across studies made direct comparison difficult. The review was limited to combined THC/CBD extracts, excluding other cannabinoid preparations.

How to read the evidence

Systematic review of six RCTs. The included trials varied in design and outcome measures, limiting the strength of combined conclusions.

When this study was published

Published in 2009. Sativex has since been approved in multiple countries for MS spasticity based on accumulating evidence, including larger subsequent trials.

The bigger picture

This review documented the evidence base at the time Sativex was being considered for regulatory approval. The subjective-objective disconnect is a recurring theme in cannabis therapeutics research and raises questions about outcome measurement in clinical trials.

Questions still open

Why do subjective and objective spasticity measures diverge? Are current objective measures sensitive enough to detect meaningful changes? Should regulatory decisions prioritize patient-reported outcomes?

Common questions

Does Sativex help with MS spasticity?

This review found patients reported meaningful improvement, but objective clinical measures did not show statistically significant changes. Subsequent larger trials have provided additional data, and Sativex has been approved for MS spasticity in several countries.

Why would patients feel better if objective measures do not change?

Spasticity is a complex symptom. Objective measures like the Ashworth scale may not capture all aspects of what patients experience. Reduced pain, improved comfort, and better sleep quality can all contribute to subjective improvement even if muscle tone measurements appear unchanged.

Read the original research

Whole plant cannabis extracts in the treatment of spasticity in multiple sclerosis: a systematic review.

BMC neurology, 9, 59

View on PubMed ↗Publisher’s paper ↗

Citation

Lakhan, Shaheen E; Rowland, Marie. (2009). Whole plant cannabis extracts in the treatment of spasticity in multiple sclerosis: a systematic review.. BMC neurology, 9, 59. https://doi.org/10.1186/1471-2377-9-59