Cannabis study: disappointing results for progressive MS

Research announced today has shown a cannabis-based drug, THC, didn't slow disability progression in people with progressive MS.

The CUPID study, conducted by researchers from Plymouth University and co-funded by the MS Society, investigated whether the main active constituent of cannabis (tetrahydrocannabinol, or THC) is effective in slowing the course of progression in MS.

Disappointingly, the study found that overall THC didn't slow disability progression. However, there was some evidence there was a beneficial effect in people who were at the lower end of the disability scale at the beginning of the study.

This benefit was only found in a small group of people, so further studies would be needed to find out how beneficial THC would be for this group.

The study

Researchers studied nearly 500 people with progressive MS from 27 centres around the UK. Participants were randomised to receive either a THC tablet or a dummy (placebo) tablet for three years. They were carefully followed to see how their MS changed or progressed over this period.

Disability progression was measured using two scales:

• a disability scale administered by neurologists (the Expanded Disability Status Scale)
• a patient report scale of the impact of MS on people with the condition (the Multiple Sclerosis Impact Scale 29)

Research continues 

Dr Doug Brown, Head of Biomedical Research at the MS Society, said: "There are currently no treatments for people with progressive MS to slow or stop the worsening of disability. The MS Society is committed to supporting research in this area and this was an important study for us to fund."

"While this study sadly suggests THC is ineffective at slowing the course of progressive MS, we will not stop our search for effective treatments. We are encouraged by the possibility shown by this study that THC may have potential benefits for some people with MS and we welcome further investigation in this area."

The CUPID study was co-funded by the MS Society, the National Institute for Health Research (NIHR) and the MS Trust.