GAITHERSBURG, MD. – A Food and Drug Administration advisory panel on Jan. 11 unanimously agreed in a 9 to 0 vote that a laparoscopically implanted device designed to treat gastroesophageal reflux disease has a favorable risk-benefit profile, providing patients who do not get adequate relief from antireflux medications an alternative to more invasive surgery,.
The FDA’s Gastroenterology–Urology Devices Panel also voted 9 to 0 that there was "reasonable assurance" that the device, the LINX Reflux Management System, was safe and effective for the indication proposed by the manufacturer: the treatment for people who are "diagnosed with pathologic gastroesophageal reflux disease (GERD) as defined by abnormal pH testing, and who continue to have chronic GERD symptoms despite anti-reflux therapy." The panel did not vote specifically on whether to recommend approval.
The sterile, single-use device is designed to augment a weak lower esophageal sphincter (LES), and is composed of titanium beads that have a magnetic core, strung together on a titanium wire, which is placed around the gastroesophageal junction at the LES. Because of the magnetic attraction between the beads, the beads rest against each other and help prevent the LES from opening at rest, therefore preventing reflux. But the magnetic attraction is disrupted when the patient swallows, allowing food and liquids to pass into the stomach. Belching and vomiting are possible, because the device does not compress the esophagus.
The manufacturer, Torax Medical Inc., conducted two prospective, uncontrolled studies of 144 patients with chronic GERD symptoms, despite long-term acid suppression treatment, in the United States and Europe. All patients received the implant.
In the pivotal study of 100 patients, 64% had normalization of pH or at least a 50% reduction in pH 12 months after device implantation, which was the primary efficacy end point. This finding was not statistically significant, based on prespecified cirtieria for significance. But the majority of patients showed improvement in scores on a scale that measures the severity of GERD symptoms and were able to reduce their daily proton pump inhibitor dosage by at least 50% at 12 and 24 months, which were secondary end points.
Almost 80% (76) of the patients had a total of 162 adverse events that were related to the device or the procedure, of which dysphagia was the most common, accounting for 76 events, followed by pain in 24 events. Some cases had to be treated with esophageal dilation, and some required device removal.
In the feasibility study of 44 patients, the majority of patients also had improvements in GERD symptoms and PPI use for up to a 3-year follow-up, with dysphagia the most common side effect, requiring two esophageal dilations and one explant.
Panelists recommended that patients be followed up for longer than the 3 years in postmarketing studies proposed by the manufacturer. The device has been available in the United Kingdom and Germany for about 2 years.
The FDA usually follows the recommendations of its advisory panels, which are not binding. Panelists have been cleared of potential conflicts of interest related to the topic of the meeting. Occasionally, a panelist may be given a waiver, but not at this meeting.