Double-Blind Study Compares Angioplasty to Sham to Treat CCSVI in MS
March 8, 2017—The University of British Columbia (UBC) announced findings from a study showing that venoplasty to open narrowed veins from the brain and spinal cord is not effective in treating multiple sclerosis (MS). UBC stated, "The conclusions about the so-called liberation therapy, which thousands of people with MS have undergone since 2009, represent the most definitive debunking of the claim that patients could achieve dramatic improvements from a one-time medical procedure." The Can$5.4 million study was jointly funded by the Canadian Institutes of Health Research (CIHR), the MS Society of Canada, and the Provinces of British Columbia, Manitoba, and Quebec.
The study was led by investigators from UBC and Vancouver Coastal Health in Vancouver, British Columbia. Lindsay Machan, MD, Associate Professor of Radiology at UBC, presented the findings at the Society of Interventional Radiology (SIR) 2017 annual scientific meeting in Washington, DC. The investigators are now preparing an article for publication in a peer-reviewed journal.
As noted by UBC, the theory of using venoplasty as an MS treatment was put forward by Paolo Zamboni, MD, who asserted that narrowing of the veins in the neck could be causing iron to accumulate in the brain and spinal cord, triggering an autoimmune response. Dr. Zamboni called his theory "chronic cerebrospinal venous insufficiency (CCSVI)" and cited several dozen cases of patients who improved after he performed venoplasty procedures on them.
Upon learning of Dr. Zamboni's anecdotal results through the news media, many patients in Canada and Europe asked for imaging of their veins and for subsequent venoplasty. But almost all Canadian physicians, citing the lack of supporting evidence, would not perform it, prompting some patients to seek the treatment in the United States, Latin America, and Eastern Europe, according to the UBC statement.
In the UBC announcement, Dr. Machan commented, "Despite the negative findings of that diagnostic study, many patients wanted to know if the venous dilation procedure could help. We were committed to meticulously evaluating this treatment with robust methods and patient-focused outcomes."
Investigator Anthony Traboulsee, Associate Professor of Neurology and Director of the MS Clinic at the Djavad Mowafaghian Centre for Brain Health, stated, "We hope these findings, coming from a carefully controlled, 'gold standard' study, will persuade people with MS not to pursue liberation therapy, which is an invasive procedure that carries the risk of complications, as well as significant financial cost. Fortunately, there are a range of drug treatments for MS that have been proven, through rigorous studies, to be safe and effective at slowing the disease progression."
In 2013, a study supported by the MS Society of Canada was published by Dr. Traboulsee et al in The Lancet (2014;383:138–145). The investigators sought to determine if narrowed veins were a distinct feature of MS and found that narrowing was just as common in people without the disease.
In the current study presented at the SIR meeting, investigators enrolled 104 people in Vancouver, Winnipeg, Montreal, and Quebec City. All patients had MS and narrowing of the jugular vein, which drains blood from the brain, or the azygos vein, which drains blood from the spinal cord. The study was double-blinded so neither the patients nor the physicians who evaluated them knew who was receiving the actual treatment or the sham procedure.
Of the 104 patients in the study, 49 underwent venoplasty and 55 patients were in a sham arm. All patients were placed under minor sedation, and all of them had a catheter threaded through an incision in the groin to the area of vessel narrowing. For those who underwent the actual treatment, the balloon was inflated once or twice; for those in the sham arm, the catheter simply remained in the narrowed area for the same amount of time, about 1 minute.
At 1-year follow-up, the venoplasty group's results were statistically the same as those in the sham group, as measured by brain imaging, standard assessments of MS symptoms, and the patients' own self-assessments.
Using MRIs of the patients' brains to count the number of new lesions in their myelin, the investigators found no difference after 6 months or 1 year between the treatment group and the sham group.
The investigators found no statistically significant difference between the treatment group and the sham group in patient symptoms, either as reported by the patients or as determined by physicians, 3 days after the procedure and a year later. Patients in both groups reported slight but equal improvements a year later; physician assessments showed no improvement in either group.
Presentation of the study prompted CIHR's Scientific Expert Working Group on MS and CCSVI to issue a statement on March 8 to communicate these findings to all interested parties and advise that CIHR does not support the use of vein dilation therapy in the management of patients with MS.
On March 8, the US Food and Drug Administration (FDA) also issued a safety communication for providers and patients regarding lack of evidence for experimental procedures ("Transvascular Autonomic Modulation") that use balloon angioplasty devices to treat autonomic dysfunction, including MS and other conditions. This safety communication supplements a 2012 FDA safety communication and an FDA warning letter addressing the risk of serious injuries and death associated with a similar experimental procedure, using the same medical devices, to treat CCSVI.