The Case For and Against Cannabis Treatment in MS: Where Did the Evidence Stand in 2004? | Research

The takeaway

A review noted that while animal studies and patient reports strongly supported cannabinoids for MS, objective clinical evidence remained lacking, with better-designed studies failing to show improvement on standard measures.

Read this if you want to understand why it took so long for cannabis-based MS treatments to gain approval despite patient enthusiasm.

Only 10 clinical reports with 78 patients worldwide; objective evidence lacking

What the researchers found

The review identified a gap between promising preclinical evidence and disappointing clinical results. Animal models of MS showed clear efficacy for cannabinoids in controlling spasticity, tremor, and clinical disease severity. Patient self-reports and anecdotal evidence also strongly suggested benefit. However, the translation to clinical proof was incomplete.

Only ten published clinical reports involving 78 patients existed at the time, with equivocal results. The somewhat better-designed studies had failed to demonstrate objective improvement on standard measures, even while patients reported subjective benefit. This disconnect between objective and subjective outcomes was a major challenge for the field.

Why it matters

This review captured the frustrating state of the field in 2004: compelling biological rationale and patient reports, but clinical trial results that did not convincingly demonstrate objective benefit. The honest assessment of this gap helped identify the need for better outcome measures and larger trials.

The numbers in context

Ten published clinical reports involving 78 individuals worldwide at the time of review.

How the study worked

This was a narrative review covering the endocannabinoid system, preclinical evidence from animal models, and clinical trial evidence for cannabinoid treatment of MS symptoms.

What this study cannot tell us

The review was written before the full results of the CAMS trial and other large studies were available. The small number of clinical reports (10, involving only 78 patients) limited the conclusions that could be drawn.

How to read the evidence

This is a narrative review honestly assessing the gap between preclinical promise and clinical evidence, providing moderate-level evidence through critical synthesis.

When this study was published

Published in 2004. The evidence base has grown substantially since, leading to Sativex approval for MS spasticity.

The bigger picture

The objective vs. subjective outcome gap identified here was subsequently addressed by the MUSEC trial and the development of patient-reported outcome measures as primary endpoints. Sativex was eventually approved based on a combination of objective and subjective evidence.

Questions still open

Were the objective measures used in early trials (like the Ashworth scale) appropriate for detecting cannabinoid effects? Has subsequent research resolved the objective-subjective disconnect?

Common questions

Why was it so hard to prove cannabis works for MS?

The standard measures used in clinical trials (like the Ashworth scale for spasticity) did not seem to capture what patients experienced. Patients reported feeling better, but the clinical scales did not show improvement. This led to a rethinking of how MS outcomes should be measured.

How many clinical studies existed for cannabis in MS in 2004?

Only ten published clinical reports existed worldwide, involving just 78 individuals total. This extremely limited evidence base was a major obstacle to establishing cannabis as a legitimate MS treatment.

Read the original research

Towards cannabis and cannabinoid treatment of multiple sclerosis.

Drugs of today (Barcelona, Spain : 1998), 40(8), 663-76

View on PubMed ↗

Citation

Croxford, J Ludovic; Miller, Stephen D. (2004). Towards cannabis and cannabinoid treatment of multiple sclerosis.. Drugs of today (Barcelona, Spain : 1998), 40(8), 663-76.