Trials of a controversial treatment for MS are set to begin, giving hope to Canadians with the disease — including several hundred in the Kamloops region.

But a representative of the Multiple Sclerosis Society of B.C. cautioned Friday there will be high demand for only 100 spaces across Canada.

Health Minister Leona Aglukkaq said Friday the Canadian trial is set to begin and will soon recruit patients. About 100 will be enrolled in the study, based initially in Vancouver and Montreal.

The trial will assess the safety of the procedure to unblock narrowed neck veins and its efficacy in improving MS symptoms.

The condition — dubbed chronic cerebrospinal venous insufficiency, or CCSVI — has been proposed as a possible cause of MS by Italian vascular surgeon Paolo Zamboni.

More than three years ago, Zamboni hypothesized that narrowed and twisted veins in the neck and chest create a back-up of blood in the brain, resulting in iron deposits that could cause the brain lesions typical of MS.

The disease causes the destruction of myelin, the protective sheath around nerves throughout the body, leading to progressive physical and cognitive disability. An estimated 55,000 to 75,000 Canadians have MS, and the county has one of the highest rates of the incurable disease in the world.

“This is really good news for people with MS,” said Multiple Sclerosis Society of Canada’s B.C. spokeswoman Suzanne Jay. “The society has spent several million assessing whether CCSVI is an option.”

Those wishing to enroll in the study should study the criteria, Jay recommended.

“There’s only 100 patients, spread over two sites,” Jay said, predicting demand will be high.

Dr. Russell Mosewich, a Kamloops neurologist, estimated upwards of 15 per cent of his patients have independently had surgery done in another country. Those patients are not eligible for the trial.

“Many of the rest would be candidates,” he said.

Mosewich welcomed the trial, saying he gets frequent questions from patients about the procedure, but there is a lack of good research to back up claims.

Dr. Anthony Traboulsee, medical director of UBC Hospital’s MS Clinic, will lead the $6-million study. Medical and ethical approval is also being sought for parts of the trial to be conducted in Quebec City and Winnipeg.

“It’s going to be a randomized-control study where patients who have the presence of CCSVI will be randomly selected to either have the venoplasty, which is dilation of the vein, or a sham treatment, which is not an actual dilation, just a pretend dilation,” Traboulsee said Friday from Vancouver.

“And after a year, the groups will switch so that everybody eventually gets the dilation of the vein.”

A venoplasty to widen veins is the same technique as an angioplasty used to expand coronary arteries; a tiny balloon is fed into the blood vessel, then expanded.

None of the participants will know which treatment they received or during which half of the study, Traboulsee said.

“The patients won’t know when they’re getting the dilation, the first time or the second time, so it doesn’t bias their interpretation of benefit,” he said.

Thousands of Canadians with MS have reportedly travelled to clinics outside the country, paying thousands of dollars for the vein-dilating procedure since Zamboni’s theory first made headlines in late 2009.

Many patients — but by no means, all — reported their symptoms had improved following CCSVI treatment, fuelling insistent calls by MS patients and their advocates to allow doctors to perform the procedure in Canada.

But with several deaths and complications attributed to the vein-widening surgery — and studies on CCSVI around the world showing mixed results at best — an expert medical panel advised Ottawa to first mount a clinical trial to test Zamboni’s theory.

Richie Kohorst, who traveled from Kamloops to Mexico in 2010 to have the procedure done, said he experienced good initial results but is suffering from some worsening symptoms since. He said news of the study will be welcome to patients and their families.

“It’s about time. I think they should give it to everybody. I know it would cost millions and millions but Canadians are doing it out of their own pocket.”

Traboulsee’s group, whose study design was chosen from among three proposals, said the research is meant to establish both safety and efficacy of the treatment.

“Safety is really important. We’ve been surveying patients who have gone out of the country for the treatment and we found a complication rate of 11 to 12 per cent. That’s what patients are reporting,” he said.

“My impression is it’s mostly related to stents and we’re not going to be using stents in our study. We don’t think the stents are the best idea at this point.”

Stents are small mesh cylinders that are inserted into blood vessels to keep them propped open. Their use in veins is controversial, as the stents can cause blot clots or migrate from their original site in some cases. Even Zamboni does not advocate their use in his CCSVI treatment.

“There has been a lot of controversy around it,” Traboulsee said of the procedure. “That’s why I think it’s important to move this forward and get some final answers to it.

Dr. Alain Beaudet, president of the Canadian Institutes of Health Research (CIHR), said MS patients will be drawn from the three provinces where the research is being conducted.

Beaudet said the study is among only a handful worldwide that are blinded, randomized-control trials, the gold standard of medical research.

“Which is critical here because we’re wondering if it’s a true effect. Is it a placebo effect? Is there really an effect?” he said from Halifax.

“I think we’re getting to the point where we need to know one way or the other, and I hope that this will bring us the answer that we’re all after.”