FDA Warns MS Stent Treatment Unproven, Possibly Deadly

The U.S. Food & Drug Administration (FDA) just issued a warning alert that a multiple sclerosis (MS) stent treatment is both unproven and potentially deadly.

Health care professionals and patients are being warned about injuries and deaths linked to use of an experimental procedure, sometimes referred to as “liberation therapy” or “liberation procedure,” used in the treatment of chronic cerebrospinal venous insufficiency (CCSVI). CCSVI is characterized by a narrowing (stenosis) of veins in the neck and chest; some experts believe that CCSVI is precursor or contributor to MS, impairing brain and upper spinal cord blood drainage.

The experimental procedure uses balloon angioplasty devices or stents to widen narrowed chest and neck veins; however, the agency has been advised of incidents of death, stroke, stent detachment and migration, damage to the treated vein, blood clots, cranial nerve damage, and abdominal bleeding linked to the experimental procedure. Specifically, the FDA announced that at least two people died from the experimental procedure, said Reuters. Another patient is now permanently paralyzed, and others suffered bleeding in the brain, suffered strokes, blood clots, or other side effects.

Stents are steel mesh coils that prop open arteries; balloon angioplasties utilize a balloon at the tip of a catheter, which opens blocked blood vessels, Reuters explained. Balloon angioplasty devices and stents are not FDA-approved for use in treating CCSVI. Because this is an unapproved procedure, there is no data on adverse events, said the FDA, wrote Reuters. Complications following CCSVI treatment can be reported through MedWatch, the FDA Safety Information and Adverse Event Reporting program.

Meanwhile, studies into the MS-CCSVI link have been inconclusive and the CCSVI diagnosis criteria have not been fully established. “Because there is no reliable evidence from controlled clinical trials that this procedure is effective in treating MS, FDA encourages rigorously-conducted, properly-targeted research to evaluate the relationship between CCSVI and MS,” said William Maisel, M.D., M.P.H., chief scientist and deputy director for science in the FDA’s Center for Devices and Radiological Health. “Patients are encouraged to discuss the potential risks and benefits of this procedure with a neurologist or other physician who is familiar with MS and CCSVI, including the CCSVI procedures and their outcomes,” Dr Maisel added.

The FDA is also advising physicians and clinical investigators planning or conducting clinical trials that use medical devices to treat CCSVI, that they must comply with FDA regulations for investigational devices. Procedures conducted are considered significant risk clinical studies and require FDA “investigational device exemption” approval. This February, the FDA sent a warning letter to a sponsor/investigator conducting a clinical study of CCSVI treatment without this mandated approval. The sponsor/investigator voluntarily closed the study.

Reuters noted that the FDA could not immediately identify the stent models involved in the unapproved treatment.

MS is a progressive, immune-mediated brain and spinal cord disorder that involves injury to nerve fiber lining—sometimes, actual nerve fibers—which leads to severe, disabling neurological symptoms. The underlying cause of MS remains unknown and there is no cure. About 2.5 million people worldwide have been diagnosed with MS.