Despite pressure from patients to fund studies into a controversial theory on multiple sclerosis, the federal health minister says there is not enough evidence to move ahead with any more studies.

Health Minister Leona Aglukkaq said Wednesday she accepted recommendations made this week by the Canadian Institutes of Health Research not to fund further studies on the "liberation treatment."

She said the federal government will instead assemble a working group to study data from seven studies of the treatment now underway.

"To ensure that we have the evidence to support this procedure, we need to do the research," Aglukkaq said.

"And once we have that, we will proceed -- if there is enough evidence from the seven research projects already underway around this subject -- we will proceed with pan-Canadian clinical trials. We will support that.

"At this point in time, we do not have the evidence to proceed."

Many MS patients have been urging quick study on the controversial treatment and the CCSVI theory behind it, which contends that blocked neck veins contribute to MS.

The CIHR said on Tuesday that, after reviewing the research so far on CCSVI and the liberation treatment, "there was unanimous agreement from the scientific experts that it is premature to support pan-Canadian clinical trials on the proposed 'liberation procedure'."

Agency President Dr. Alain Beaudet said the team of experts they consulted wasn't convinced that the CCSVI theory was sound, nor that the liberation procedure is safe nor effective.

In response to question from reporters Wednesday, Beaudet explained that the liberation treatment, which involved threading a needle into neck veins to open them, carries risk.

"Balloon angioplasty is relatively safe -- and I think we have to insist on relatively," he said. "Any procedure where you inject a catheter in a vein, where you compress the vein, where you risk damage to the internal sheath of the vein is not without risk."

Aglukkaq said she looked forward to the outcome of studies currently underway, which are expected to take two years to complete.

"These studies will inform decisions about moving forward with any pan-Canadian clinical trials on a treatment to unblock veins. I will immediately establish a scientific expert working group to monitor and keep me informed of progress on these and other studies. More details on this working group will be available in the near future," she said.

But many MS patients and some doctors are angry with that approach. Cardiovascular thoracic surgeon Dr. Sandy McDonald, who has researched the "liberation treatment," says the federal government's decision is a disappointment.

McDonald believes that Canadian researchers would have been best positioned to answer some of the important questions about the procedure and CCSVI.

"We have a world-class health organization, we have world-class facilities, and we should be doing world-class research by people who know how to do it," McDonald told CTV's Canada AM from Barrie, Ont. Wednesday.

He conceded that there hadn't been much research so far on the treatment, but notes that more research is about to be published. He wondered: if the agency didn't think there was enough research, why didn't it want to fund studies of its own?

"What we're saying is that the research that has been done is flawed and is not good enough, and yet we're not prepared to do the research ourselves," he said.

"If the research others are doing isn't good enough, then we need to do the research here."

McDonald says while he cautions patients from going abroad for medical treatment, he understands that patients who can afford to -- and even those who can't -- will go wherever they have to, to try this treatment.

"I personally don't endorse medical tourism," he said. "But the sad part is that the stance the CIHR has taken actually puts people in the position where they're forced to look at medical tourism for a procedure that should be available in Canada, at least on a compassionate basis."