Monday, 14 October, 2002, 13:45 GMT 14:45 UK
Hundreds of patients have been recruited to take part in clinical trials
of cannabis based in Devon.
The research, by Dr John Zajicek at the Peninsula Medical School, is to investigate the use of canaboids on the symptoms of multiple sclerosis (MS).
About 44 patients were recruited in Plymouth in January last year and now that figure has risen to 667 worldwide.
Thirty three medical centres worldwide are contributing to Dr Zajicek's research, which should be completed by February 2003.
Dr Zajicek's work is being funded by the Medical Research Council, which has contributed more than £1m.
Dr Zajicek said he thinks there may be real health benefits for MS patients and some people have responded very well to treatment.
After the results are released, he said it is then down to parliament to decide what to do.
Dr Zajicek said: "All the indications are that they're going to take a lot of notice of the results of this study.
"This is the biggest study into cannabis ever produced and I think it will inform the politicians and the regulators of medicines as to how useful these drugs are going to be.
"We're already looking at ways to get these drugs on the market."
But for those finishing trials, it could be a long wait before they have access to the medication.
Hazel Walker, from Plymouth, was among the first to be recruited to the trials.
She said the drug helped her but now she is having to manage without it because her part in the research has ended.
She also believes properly prescribed medication is the best way to treat MS.
She said: "I hope that it is made available because it did make a lot of difference in my life."
Cannabis still remains a controversial substance.
Despite plans to reclassify it from a Class B drug to Class C, the Home Office says recreational users can still be arrested for having it.
However, a man from west Wales was acquitted by magistrates after he said he used it for medical purposes last week.
Brad Stephens, who has the spinal condition cervical spondylosis, had been prescribed morphine.
He argued conventional medicines were not strong enough but cannabis
relieved "underlying ache and numbness" he suffered from.
© 2002, BBC