Electrical stimulation of the lower sphincter appears to be safe and effective in patients with refractory gastroesophageal reflux disease, according to an interim analysis of a multicenter trial.
These findings follow results from a single-center study that previously demonstrated that electrical stimulation improved long-term outcomes in refractory gastroesophageal reflux disease.
“This technology is one we’re considering to answer the needs of those who get insufficient relief from proton pump inhibitors (PPIs), without the adverse effects and complexity of the established surgical procedure,” Edy Soffer, MD, from the Keck School of Medicine in Los Angeles, told Medscape Medical News.
Dr. Soffer presented the research here at the American College of Gastroenterology (ACG) 2013 Annual Scientific Meeting and Postgraduate Course.
PPIs are the standard of care for gastroesophageal reflux disease, but as many as 40% of patients do not have a satisfactory response to treatment. Another alternative is Nissen fundoplication, a surgical procedure to reinforce the lower esophageal sphincter, but it can have side effects and sometimes needs to be repeated.
The study included patients who had had a partial response to PPI therapy and who had health-related quality-of-life scores higher than 20 when off PPI, and a 5-point or higher improvement when on PPI.
To date, 25 participants have undergone implantation with the device. A total of 24 have remained on electrical stimulation. One patient experienced small-bowel trocar perforation during the implant procedure; this was successfully repaired, and the device was removed. In all, 20 patients have completed their 3-month evaluation, and 17 have completed their 6-month evaluation.
At both 3 months and 6 months, patients experienced an improvement in symptoms and esophageal pH, and PPIs were eliminated for the majority of the patients who reached the 6-month endpoint.
Out of a total of 50 adverse events reported in 17 patients, only 2 were serious, including the trocar perforation and an atrioventricular nodal reentrant tachycardia, which was reportedly not device- or procedure-related.
Of the other 48 events, 26 were possibly or probably related to the device or procedure, and 1 was definitely related to the procedure. The researchers noted 2 instances of mild, transient dysphagia in patients undergoing hiatus closure at the time of device implantation, but both cases resolved within 4 weeks with no intervention. There were no stimulation-related gastrointestinal side effects or sensations.
“About two thirds of the patients in the trial have made it to 6 months, and the data pretty much follow the patterns seen in previous studies,” Dr. Soffer said. “There’s a significant and sustained improvement in the patients who have reached the endpoint. This is an open-label trial, so symptoms could be affected by the placebo effect, but acid exposure is an objective measure, and it is significantly improved.”
There have been no serious adverse events related to the device or to electrical stimulation in any of the trials to date, he pointed out.
Others said that they agree that the objective measure is key. “I think it’s a real strength of the study that they objectively quantified the amount of acid reflux before and after the intervention,” Marcelo Vela, MD, from the Baylor College of Medicine in Houston, Texas, told Medscape Medical News. “The data are encouraging, but it’s very early. It’s a multicenter trial, so it’s more robust than previous data, but we will need a sham-controlled study to see whether it really continues to look good.”
This study was funded by Endostim, which manufactures the device used in the procedure. Dr. Soffer is a shareholder in the company. Dr. Vela reports no relevant financial relationships.
American College of Gastroenterology (ACG) 2013 Annual Scientific Meeting and Postgraduate Course: Abstract 2. Presented October 14, 2013.
Jim Kling