“The LINX Reflux Management System is a sterile, single-use, surgically placed device used to treat the symptoms associated with GERD,” as described by Christy Foreman, director of the Office of Device Evaluation in FDA’s Center for Devices and Radiological Health. “LINX offers an option to patients and their health care providers and is an alternative to current surgical procedures.”
The LINX system is composed of a series of titanium beads, each with a magnetic core, connected together with independent titanium wires to form a ring shape. It is implanted at the lower esophageal sphincter (LES), a circular band of muscle that closes the last few centimeters of the esophagus and prevents the backward flow of stomach contents.
The force of the magnetic beads is designed to provide additional strength to keep a weak LES closed. Upon swallowing, the magnetic force between the beads is overcome by the higher pressures of swallowing forces, and the device expands to accommodate a normal swallow of food or liquid. Once the food passes though the LES, the device returns to its resting state.
The company conducted a feasibility study of 44 patients at four centers with a five-year follow-up plan. In this study, the total mean GERD Health-Related Quality of Life symptom scores improved from a mean baseline value of 25.7 to 3.8 and 2.4 at 1- and 2-year follow-up, representing an 85% and 90% reduction, respectively (P < 0.0001). Complete cessation of PPI use was reported by 90% of patients at 1 year and by 86% of patients at 2 years. Early dysphagia (swallowing difficulty) occurred in 43% of the patients and self-resolved by 90 days.
In addition, the company conducted a pivotal study of 100 patients at 14 centers with a five-year follow-up plan. Patients enrolled had GERD and chronic GERD symptoms, despite medical therapy. Results from both the feasibility and pivotal trials indicate that the benefits obtained with the LINX Reflux Management System outweigh its risks.
As a condition of approval, the company will institute a required training program to educate new users on patient selection, device implantation and post-procedural care of patients treated with LINX.
The most common adverse events experienced with the LINX included difficulty swallowing, pain when swallowing food, chest pain, vomiting, and nausea.
It is important to note that patients with LINX will no longer be able to undergo Magnetic Resonance Imaging (MRI) procedures. The magnetic beads interfere with the machine and can cause the device to be damaged and the patient to be injured.
The LINX technology is very exciting, but the enthusiasm should be tempered as the studies performed were on a somewhat small patient population. Given the fact that a metallic, magnetic device is placed permanently (although it can, apparently, be removed surgically), the long-term safety and efficacy should be established in clinical practice. The studies wre performed by leading experts in the field of surgery and the experience may be different as community physicians undergo a learning curve in adopting the procedure in their practices and fully comprehend appropriate patient selection.
Furthermore, this procedure need be compared to formal surgical techniques like the Nissen fundoplication or to transoral procedures such as the EsophyX Transoral Incisionless Fundoplication (TIF).