New Data on Sativex for MS Spasticity: No Cognitive Decline and No Driving Impairment | Research

The takeaway

Additional studies involving over 1,000 MS patients found Sativex did not cause cognitive decline after 12 months and did not impair standard driving ability.

Read this if you use or are considering Sativex for MS spasticity and want to know about long-term safety.

No cognitive decline after 12 months; real-world doses (5-6 sprays/day) lower than trials (8+)

What the researchers found

A randomized, placebo-controlled long-term trial demonstrated that THC:CBD spray (Sativex) was not associated with cognitive decline, depression, or significant mood changes after 12 months of treatment. This addressed a key concern about long-term cannabinoid therapy.

A prospective observational pilot study of 33 patients (ages 33-68) found that Sativex did not adversely influence standard driving ability in patients with moderate to severe MS spasticity.

Patient registry data from the UK, Germany, and Spain reinforced the efficacy and safety observed in Phase III trials. Notably, patients in real-world practice used lower average doses than those in clinical studies (5-6.4 vs. >8 sprays/day), and effectiveness was maintained. In the German/UK registry, 45% of patients had been treated for over 2 years with no additional safety concerns identified.

Why it matters

Long-term safety data is essential for medicines used to treat chronic conditions like MS spasticity. The absence of cognitive decline after 12 months and the lack of driving impairment are reassuring findings for patients and prescribers concerned about chronic cannabinoid use.

The numbers in context

Over 1,000 additional patients studied. No cognitive decline at 12 months. Driving not impaired in 33-patient pilot. Real-world dosing: 5-6.4 sprays/day (vs. >8 in trials). 45% of registry patients treated for >2 years.

How the study worked

This is a review of multiple new data sources available in 2013: a randomized placebo-controlled long-term follow-up trial, a prospective observational driving study, and patient registries from the UK, Germany, and Spain. Together, these sources covered approximately 1,000 additional patients beyond the original Phase III trials.

What this study cannot tell us

The driving study was a small pilot (n=33). Registry data is observational and subject to selection bias (patients who continue medication may be those who tolerate it well). The cognitive study assessed specific standardized measures and may not capture all aspects of cognitive function. The review was published in a supplement likely supported by the manufacturer.

How to read the evidence

This review combines data from an RCT, observational study, and patient registries, providing moderate overall evidence for long-term safety.

When this study was published

Published in 2014. Long-term registry data on Sativex has continued to accumulate since.

The bigger picture

These post-marketing data strengthen the safety profile of Sativex for long-term use in MS spasticity. The finding that real-world doses are lower than trial doses while maintaining effectiveness suggests the drug may be more efficient in practice than clinical trials indicated.

Questions still open

Does the lower real-world dosing pattern reflect patients finding their optimal dose or under-dosing due to side effects? Would even longer follow-up (5+ years) reveal delayed effects? How do these cognitive findings compare to other MS treatments?

Common questions

Does Sativex impair driving?

A pilot study of 33 patients found no adverse effect on standard driving ability. However, individual responses vary, and patients should exercise caution, especially when starting treatment or adjusting doses.

Why do patients use lower doses in practice than in clinical trials?

Clinical trials often titrate to maximum tolerated doses. In practice, patients tend to find a lower dose that provides adequate symptom relief with fewer side effects. This pattern is common across many medications.

Read the original research

THC:CBD spray and MS spasticity symptoms: data from latest studies.

European neurology, 71 Suppl 1, 4-9

View on PubMed ↗Publisher’s paper ↗

Citation

Rekand, Tiina. (2014). THC:CBD spray and MS spasticity symptoms: data from latest studies.. European neurology, 71 Suppl 1, 4-9. https://doi.org/10.1159/000357742