Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


UK trial results on value of cannabis for multiple sclerosis patients


Researchers funded by the UK Medical Research Council (MRC) have found mixed evidence about the value of cannabis-derived treatments for people with Multiple Sclerosis (MS) but conclude that such treatments may be of benefit for some patients.

The researchers found little objective evidence that cannabis benefits people with MS but, subjectively, a majority of patients felt cannabis improved some of their symptoms.

The results of the world’s largest study to assess the medicinal potential of cannabinoids to treat MS patients are published in this week’s edition of The Lancet.

The research team based at the Peninsula Medical School and the University of Plymouth was led by Dr. John Zajicek, Consultant Neurologist and Associate Medical Director of Research and Development at Plymouth Hospitals NHS Trust. The other principal investigator was Professor Alan Thompson, Consultant Neurologist at the National Hospital for Neurology and Neurosurgery, University College Hospitals, London. The trial that involved 33 neurology and rehabilitation centres across the UK was funded by the MRC and supported by the MS Society.

The three year trial of more than 600 patients from across the UK set out to look at whether cannabinoids can reduce muscle stiffness, known as spasticity, in the arms and legs of MS patients and to assess their general wellbeing in relation to other symptoms.

Participants in the trial were randomly assigned to oral capsules containing either cannabis extract, Tetrahydrocannabinol (THC, - an active compound found in cannabis), or a placebo and treated for 15 weeks. No patient was left without medication to manage their illness. The trial treatments were administered in addition to participants’ own standard MS medication. The patients were not told which treatment they were taking.

The researchers found that when spasticity was assessed clinically using a well-established measure known as the Ashworth scale1 there was no overall detectable change in spasticity in the patients.

Four secondary measures were also used in the study: time to walk ten metres for mobile patients; a range of scales to assess disability and well-being; some measures of specific symptoms; and finally face-to face questions about the value of medication at the end of the study.

In face-to-face interviews, 576 patients provided answers to the end of study questions. Around two thirds of patients on the cannabis-based treatments said they felt their spasticity had improved, as did almost half of the patients taking a placebo, or dummy pill.

A benefit of cannabis-based medicine was also seen in results from the walking time. There was no benefit seen in any of the scales measuring general disability or wellbeing.

Patients were also asked to complete self assessment questionnaires about a range of symptoms associated with MS including irritability, depression, tiredness, spasticity, shake/tremor, pain, sleeplessness, spasms and lack of energy. Just over half the patients who completed the questionnaires on the cannabis-based treatments said spasticity had improved, but just over a quarter of these patients said they felt their symptoms had got worse. Overall, more patients taking active treatment said they experienced improvement in spasticity, pain, spasms and sleep compared to those taking placebo.

The researchers said that the results needed to be interpreted with caution as around three-quarters of patients in the active treatment group correctly guessed that they were taking active medication, compared to around half of the placebo group, who guessed they were not.2

Dr. Zajicek said: "The results of this study present an interesting and complex picture of the value of cannabis-derived medicines for treating MS. The primary aim of the trial was to measure, as objectively as possible, the actual physical changes in limb spasticity in MS patients, and we found no evidence of this.

"Although we based the study around spasticity, we also wanted to capture any treatment effects among the other important symptoms described by people with MS. When patients were asked to describe how they felt their symptoms, including spasticity, had been affected, the picture was very different. They felt some of the impact of their painful and distressing symptoms had been eased.

"We did see a high ’placebo effect’ in this trial and it may be indicative of how much patients gain by taking part in clinical trials, irrespective of the treatment they are given.

"Patients experienced very few side-effects from the treatments and, given that how a patient feels is an important part of improving health, cannabis-based treatments may be of benefit to some patients."

Professor Colin Blakemore, Chief Executive of the Medical Research Council, said: "Science isn’t always black and white and this work underlines the importance of funding large-scale clinical trials of possible treatments so the evidence can be weighed up.

"Clinical research is at the heart of the MRC’s aim to improve health and we will continue to use clinical trials to put treatment theories to the test, across all areas of health."

1. The Ashworth scale is a score of spasticity. It is an assessment of biological impairment, rather than disability or handicap and is dependent upon the estimation of the physician or physiotherapist.

2. Patients’ guesses were not confirmed to them. It was important to keep the trial ’blinded’ to retain the integrity of the data, so for the duration of the trial patients were not told what treatments they were receiving.

3. The Medical Research Council (MRC) is a national organisation funded by the UK tax-payer. Its business is medical research aimed at improving human health; everyone stands to benefit from the outputs. The research it supports and the scientists it trains meet the needs of the health services, the pharmaceutical and other health-related industries and the academic world Web site at:

4. The MRC grant for the CAMS (Cannabinoids in MS) trial was awarded in December 1999.

5. Cannabinoids are natural chemicals found in cannabis, that all have a similar chemical structure and which have been shown to act on specific targets found in the body. The cannabis extract contains 60 different cannabinoids. THC is commonly believed to be the most active compound in cannabis.

6. It is estimated that around 85, 000 people in the UK have multiple sclerosis, the most common disabling neurological disease affecting young adults in the Western world.

7. The Lancet is an international general medical journal.

Source: Medical Research Council Media Release

Chris Pook | EurekAlert!
Further information:

More articles from Health and Medicine:

nachricht Advanced analysis of brain structure shape may track progression to Alzheimer's disease
26.10.2016 | Massachusetts General Hospital

nachricht Indian roadside refuse fires produce toxic rainbow
26.10.2016 | Duke University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel light sources made of 2D materials

Physicists from the University of Würzburg have designed a light source that emits photon pairs. Two-photon sources are particularly well suited for tap-proof data encryption. The experiment's key ingredients: a semiconductor crystal and some sticky tape.

So-called monolayers are at the heart of the research activities. These "super materials" (as the prestigious science magazine "Nature" puts it) have been...

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Prototype device for measuring graphene-based electromagnetic radiation created

28.10.2016 | Power and Electrical Engineering

Gamma ray camera offers new view on ultra-high energy electrons in plasma

28.10.2016 | Physics and Astronomy

When fat cells change their colour

28.10.2016 | Life Sciences

More VideoLinks >>>