CANNABIS STUDY ENCOURAGING FOR MS

The biggest UK study of cannabis-based drugs has shown evidence for a
long-term benefit in easing the symptoms of multiple sclerosis (MS).

"There is some evidence of a long-term effect," Dr John Zajicek, who
heads the trial, confirmed to the BA Festival of Science at Exeter
University.

He also said the data so far "were consistent" with the idea the drugs
could arrest nerve death in sufferers.

He was presenting results that update a study published in The Lancet
last year.

This 15-week research project revealed patients using cannabinoid
compounds could find relief from some of the painful symptoms of MS.

But an analysis of the data suggested there was little reduction in
spasticity among the research subjects - one of the key tests used to
assess the drugs.

Spasticity refers to feelings of stiffness and a wide range of
involuntary muscle spasms or sudden movements.

Speaking at the annual British Association meeting, Dr Zajicek, from
the Peninsula Medical School in Devon, said this assessment might have
been premature.

Longer-term monitoring, he said, had now shown patients experiencing
significant improvement in this area.

Continued Support

In MS, the protective sheath that surrounds nerves (myelin) wastes
away, leaving scar tissue known as a sclerosis. Sometimes the nerve
fibre itself is damaged.

This disrupts the ability of the nerves to conduct electrical impulses
to and from the brain, producing the various symptoms of MS. These
include pain, deadening fatigue, problems with sight, mobility and
coordination.

"We have generated some very interesting results which suggest there
may be a potential long-term benefit from these drugs," Dr Zaijcek
told journalists.

"There was evidence of an effect on spasticity and on
disability."

Asked whether cannabis might work by arresting the death of nerve
cells in MS sufferers, Dr Zajicek answered: "Our results are certainly
consistent with that hypothesis."

Patients were given up to 25mg per day of either whole cannabis
extract in pill form, a tetrahydrocannabinol (THC) pill, or a placebo.
The first trial, with 667 volunteers, lasted 15 weeks and was
published in The Lancet in November.

These subjects were then asked if they wanted to participate in a
further 52-week trial. About two-thirds of the original participants
signed up for this long-term study.

A strong beneficial effect on symptoms of the disease was reported by
patients throughout the 15-week trial and the one-year study. But this
did not by itself demonstrate an underlying physical basis for this
effect, Dr Zajicek admitted.

"What we've been trying to do is to have some objective, independent
evidence of that," said Dr Zajicek.

Test of Safety

Asked whether he thought cannabis should be approved as a medicine, Dr
Zajicek answered: "I think the licensing agencies need to assess all
the evidence and we need further, long-term studies before we make
that decision."

"This comes with lots of caveats. The experiment was only designed for
a 15-week trial. We followed the subjects up expecting to find out
only whether cannabis was safe in the longer term.

"But some of the experimental data emerged over the course of our
study."

In the last 15 years, scientists have discovered a variety of
cannabis-like chemicals (or cannabinoids) in the brain.

They reduce the amount of neurotransmitters that mediate communication
between nerve cells.

Certain cannabinoids may have more of an effect than others, Dr
Zajicek said.

These cannabis-like chemicals have been used as treatments for
increasing appetite associated with cancer and Aids, as well as
various movement disorders.