Cannabis Extract Capsules Reduced Spasticity in MS Patients Who Took Enough of the Medication | Research

The takeaway

In a crossover trial of 57 MS patients, cannabis extract capsules showed no benefit in the full group, but the 37 patients who took at least 90% of their prescribed dose had significantly fewer spasms and improved mobility.

Read this if you have MS-related spasticity and want to know what clinical trials have shown about cannabis extract capsules.

Spasm frequency improved significantly (P = 0.013) in patients who took at least 90% of prescribed dose

What the researchers found

Researchers enrolled 57 MS patients with poorly controlled spasticity into a randomized, double-blind, placebo-controlled crossover study during inpatient rehabilitation. Patients received capsules standardized to 2.5 mg THC and 0.9 mg CBD each, escalated from 15 to a maximum of 30 mg THC per day.

In the full intention-to-treat analysis of 50 patients, there were no statistically significant differences between cannabis extract and placebo. However, trends favoring active treatment appeared for spasm frequency, mobility, and getting to sleep.

In the 37 patients who took at least 90% of their prescribed dose (the per-protocol analysis), improvements in spasm frequency (P = 0.013) and mobility (P = 0.01) reached statistical significance. Minor adverse events were slightly more frequent during active treatment but were generally mild.

Why it matters

The split between intention-to-treat and per-protocol results highlights a common challenge in cannabis research: dosing compliance matters. When patients took enough of the medication, measurable benefits emerged. This distinction is important for understanding how cannabis-based medicines might work in clinical practice.

The numbers in context

57 patients enrolled. 50 included in intention-to-treat analysis. 37 completed per-protocol analysis (took 90%+ of dose). Capsules contained 2.5 mg THC and 0.9 mg CBD each. Spasm frequency improvement P = 0.013 in per-protocol set. Mobility improvement P = 0.01 in per-protocol set.

How the study worked

This was a prospective, randomized, double-blind, placebo-controlled crossover study conducted during inpatient rehabilitation. Fifty-seven MS patients received standardized cannabis extract capsules (2.5 mg THC and 0.9 mg CBD each) with dose escalation from 15 to 30 mg THC daily. Outcomes included daily self-reported spasm frequency, Ashworth Scale, Rivermead Mobility Index, 10-m timed walk, nine-hole peg test, and cognitive tests.

What this study cannot tell us

The intention-to-treat analysis did not show significant benefits. The per-protocol analysis, while positive, excludes patients who could not tolerate the full dose, potentially inflating the apparent benefit. The crossover design during inpatient rehabilitation may not reflect real-world use. Sample size was relatively small.

How to read the evidence

Randomized, double-blind, placebo-controlled crossover trial, but the primary intention-to-treat analysis was not significant. Positive results come from the per-protocol subset.

When this study was published

Published in 2004. Cannabis-based medicines for MS have continued to be studied, with Sativex (nabiximols) receiving approval in several countries since this trial.

The bigger picture

This trial is part of a body of research from the early 2000s testing cannabis-based medicines for MS spasticity. The finding that benefits only reached significance in compliant patients is a pattern seen across several cannabis trials, suggesting that adequate dosing is necessary for therapeutic effects to emerge.

Questions still open

Why did some patients not complete the full dosing regimen? Would longer treatment periods or different dosing schedules produce significant benefits in the full treatment group?

Common questions

Did the cannabis extract help all MS patients with spasticity?

Not in the full analysis. When all patients were included regardless of how much medication they took, no statistically significant benefit was found. Benefits only reached significance in the subset who took at least 90% of their prescribed dose.

What side effects did patients experience?

Minor adverse events were slightly more frequent during active treatment, and toxicity symptoms were more pronounced during the active phase, but effects were generally described as mild.

Read the original research

Efficacy, safety and tolerability of an orally administered cannabis extract in the treatment of spasticity in patients with multiple sclerosis: a randomized, double-blind, placebo-controlled, crossover study.

Multiple sclerosis (Houndmills, Basingstoke, England), 10(4), 417-24

View on PubMed ↗

Citation

Vaney, C; Heinzel-Gutenbrunner, M; Jobin, P; Tschopp, F; Gattlen, B; Hagen, U; Schnelle, M; Reif, M. (2004). Efficacy, safety and tolerability of an orally administered cannabis extract in the treatment of spasticity in patients with multiple sclerosis: a randomized, double-blind, placebo-controlled, crossover study.. Multiple sclerosis (Houndmills, Basingstoke, England), 10(4), 417-24.