A Saskatchewan advocate for the so-called liberation multiple sclerosis therapy says now is not the time to back away from testing the procedure.

Michelle Walsh, who has MS, said Tuesday she was disappointed and saddened to learn that a clinical trial for the therapy has been cancelled.

"I believe that we owe it to our patients of this province to continue forth and not back down," Walsh said from her home in Beechy, Sask. "There is something to this."

Liberation treatment involves opening up neck veins with balloon angioplasty, the same procedure used to unblock coronary arteries.

The treatment is based on a hypothesis by Italian vascular surgeon Dr. Paolo Zamboni that a condition he dubbed chronic cerebrospinal venous insufficiency, or CCSVI, may be linked to multiple sclerosis. The theory suggests that narrowed neck veins create a backup of blood that can lead to lesions in the brain and inflammation.

Saskatchewan had planned to spend $2.2 million to have 86 patients join a double-blind trial at a medical centre in Albany, N.Y. Half of those participating would have received liberation therapy and half would get a placebo procedure. The patients would not know which one they got for several years.

The centre has told the province the trial has been cancelled because it couldn't get enough volunteers for a valid result.

Just under 200 people were needed. So far, six patients from Saskatchewan had joined the trial.

Walsh underwent liberation therapy in Bulgaria in 2010 and wasn't eligible for the clinical trial.

She said the results of a trial would be important, noting the high MS rate in Saskatchewan. Canada has one of the highest rates of MS in the world at 240 cases per 100,000 people. In the Prairies, the rate is even higher at 340 per 100,000 people.

"I was hoping like everyone else that this would proceed through and we would have some more answers because this is really leading Canada in the way of the science," she said.

Some studies have raised doubts about the effectiveness of liberation therapy and have questioned the benefits when weighed against the risks of complications from the operation.

A small clinical trial out of the University of Buffalo found in March that the intervention did not improve symptoms.

The study of 30 MS patients concluded that the treatment is safe, but researchers said it showed no benefit on numerous measures of symptoms, disease progression or quality of life.

As well, MRI scans showed some patients had increased brain lesions, one of the hallmarks of the progressive neurological disease, after undergoing the procedure.

But Walsh is a believer.

She said MRIs showed no new lesions on her brain after treatment and existing lesions were smaller.

"I now have the living proof that my MS has not progressed for three years and I'm still not in that wheelchair they fitted me for."

Saskatchewan was the first province to pledge clinical trials when it put up $5 million and issued a call for proposals in October 2010. The goal was to proceed with clinical trials by the spring of 2011. A few months later it was revealed that only one proposal had been received and it didn't meet criteria set by an expert panel.

Premier Brad Wall announced in January 2012 that the province would join the Albany clinical trial.

Saskatchewan Health Minister Dustin Duncan said Monday that the province would like to be involved in another double-blind study. He said MS research may also continue outside of liberation therapy.

Walsh said she's putting together a proposal for Duncan.

"Oh, I'm not done yet. I'm far from over. This file is definitely not closed," she said.

"I'm trying to get a meeting with the health minister to just really go back to the drawing board and see what we can do now."