On 10 May 2012, the US Food and Drug Administration (FDA) released an alert about injuries and death associated with the use of an experimental procedure using balloon angioplasty devices or stents, sometimes called “liberation therapy” or the “liberation procedure”, to treat chronic cerebrospinal venous insufficiency (CCSVI).
Some researchers believe that CCSVI, which is characterised by stenosis of veins in the neck and chest, may cause multiple sclerosis or may contribute to the progression of the disease by impairing blood drainage from the brain and upper spinal cord. However, the FDA stated, studies exploring a link between multiple sclerosis and CCSVI are inconclusive, and the criteria used to diagnose CCSVI have not been adequately established.
“Because there is no reliable evidence from controlled clinical trials that this procedure is effective in treating multiple sclerosis, FDA encourages rigorously-conducted, properly-targeted research to evaluate the relationship between CCSVI and multiple sclerosis,” said William Maisel, 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 multiple sclerosis and CCSVI, including the CCSVI procedures and their outcomes.”
The experimental procedure uses balloon angioplasty devices or stents to widen narrowed veins in the chest and neck. However, the FDA has learned of death, stroke, detachment and migration of the stents, damage to the treated vein, blood clots, cranial nerve damage and abdominal bleeding associated with the experimental procedure. Balloon angioplasty devices and stents have not been approved by the FDA for use in treating CCSVI.
The FDA is notifying physicians and clinical investigators who are planning or conducting clinical trials using medical devices to treat CCSVI that they must comply with FDA regulations for investigational devices. Any procedures conducted are considered significant risk clinical studies and require FDA approval, called an investigational device exemption.
In February 2012, the FDA sent a warning letter to a sponsor/investigator who was conducting a clinical study of CCSVI treatment without the necessary approval. The sponsor/investigator voluntarily closed the study.
The FDA has also announced that complications following CCSVI treatment can be reported throughMedWatch, the FDA Safety Information and Adverse Event Reporting program.
The FDA said that it will continue to monitor reports of adverse events associated with “liberation therapy” or the “liberation procedure” and keep the public informed as new safety information becomes available.
On 10 May, in response to the FDA’s alert, the Society of Interventional Radiology (SIR) stated: “SIR supports and agrees with the FDA’s recommendations to encourage research on CCSVI and the current knowledge regarding the safety and effectiveness of treatment procedures. SIR also agrees that clinical research of CCSVI should be performed through well-designed clinical trials, which should require approval through the FDA investigational device exemption programme”.
On 17 April 2012, the 34th Charing Cross International Symposium, London, UK, held a session on CCSVI which opened with a great debate titled: “CCSVI is an entity and a subset of multiple sclerosis”. Paolo Zamboni, Ferrara, Italy, and Manish Mehta, Albany, United States, presented their arguments for the motion and Alun Davies with Richard Nicholas (both from London, UK) were against the motion. After the debate, 63% of delegates voted against the motion: “CCSVI is an entity and a subset of multiple sclerosis”.