Gastroparesis treatment 2020 news

January 20 th 2020 Hand-Held Stimulator Shows Promise in Gastroparesis Gastroenterology & Endoscopy News A hand-held device that delivers transcutaneous vagal nerve stimulation provides short-term relief of symptoms and accelerates gastric emptying in patients with idiopathic gastroparesis, according to a small pilot study. The early results indicate that noninvasive, self-administered vagal nerve stimulation (nVNS) could be a helpful new therapy, said Ronnie Fass, MD, the director of the Esophageal and Swallowing Center at MetroHealth Medical Center in Cleveland. “Transcutaneous VNS is a promising noninvasive technique with a potential to improve both subjective and objective clinical outcomes in patients with gastroparesis,” said Dr. Fass, who was not involved in the research. “The device was able to improve an array of gastroparesis-related symptoms, the Gastroparesis Cardinal Symptom Index [GCSI] and gastric emptying. While these results are very exciting with a clear potential for making this device part of our therapeutic armamentarium for gastroparesis, a larger study is needed to establish the value of this device in clinical practice.” The researchers presented their findings at the 2019 annual meeting of the North American Neuromodulation Society. image The nVNS device used in this study—the gammaCore hand-held vagal nerve stimulator (electroCore)—is FDA cleared and marketed for the treatment of migraine and cluster headaches. The rationale for evaluating the device in patients with idiopathic gastroparesis stems from both its similarities and dissimilarities to gastric electrical stimulation with the Enterra device (Medtronic), according to study investigator Linda Nguyen, MD, of the Division of Gastroenterology and Hepatology at Stanford University School of Medicine, in California. “The misconception is that Enterra is a gastric pacemaker, but it does not pace the stomach. It is thought to work through modulation of vagal fibers,” Dr. Nguyen said. Although the mechanism of action is similar, nVNS is transcutaneous, so no surgery is required and therapy can be easily discontinued if patients do not experience symptom relief. An added benefit is that nVNS can potentially be used by patients with milder symptoms, unlike gastric electrical stimulation, which is reserved for medically refractory symptoms only, she said. A previous study of nVNS in gastroparesis found that of 23 patients, eight experienced significant symptom improvement after three weeks of use, for a rate of 35% (Frontline Gastroenterol 2017;8[4]:325-330). To advance this research, Dr. Nguyen and her colleagues aimed to assess the effectiveness of nVNS for gastroparesis symptoms as well as gastric emptying and autonomic function. They enrolled 15 patients with idiopathic gastroparesis (median age, 34 years; 87% women; 80% white). All patients self-administered VNS twice daily for four weeks after a two-week run-in period, followed by a four-week washout period. Each of the two daily treatments was administered for two minutes on each side of the neck for a total of eight minutes daily. With each treatment, the voltage was increased until the lip twitched to indicate that the facial nerve was engaged. The investigators evaluated symptoms using the GCSI-Daily Diary (GCSI-DD) before, during and after VNS, and administered the spirulina gastric emptying breath test and autonomic function testing before and after VNS. The primary end point was defined as a 0.75-point reduction in the one-week mean composite daily GCSI-DD score. Six patients (40%) achieved the primary end point and were considered responders, with significant improvements in all cardinal symptoms of gastroparesis. Symptom improvement persisted after the four-week washout period but did not remain significant, according to the researchers. VNS also accelerated gastric emptying by 26 minutes (half time), they reported, but this was of borderline significance (P=0.05). A longer duration of VNS use was associated with greater symptomatic improvement, suggesting that long-term use could be beneficial. Short-term use did not normalize autonomic dysfunction. None of the patients reported any adverse events related to treatment. These results are “very impressive,” but there are several caveats, according to Pankaj J. Pasricha, MD, the director of the Johns Hopkins Center for Neurogastroenterology in Baltimore. “This was not a controlled trial, so there is a powerful placebo effect of putting something that gives you an electrical buzz to your neck,” he said. The clinical effects, although statistically significant, “aren’t very robust in terms of effect size, which is less than what most people would think is clinically meaningful,” Dr. Pasricha added. “Even if these results are validated in a controlled trial, if that’s the effect size we get, it’s probably not going to be a stand-alone treatment option, though it may augment other forms of therapy.” Dr. Nguyen agreed. “Not everyone benefits from nVNS,” she said. “Therefore, I foresee this as one tool that is available to patients which can be used alone or in combination with medications that are currently being studied for the treatment of gastroparesis.” —Adam Leitenberger The study was funded by a grant from Colleen and Robert D. Haas and gammaCore devices were supplied by electroCore. Dr. Pasricha reported that he is a consultant to Vanda Pharmaceuticals, the founder of Neurogastrx and also is involved in the development of several devices that modulate gastrointestinal function and the gut–brain axis. Dr. Fass reported no relevant financial conflicts of interest. He i s a member of the editorial board of Gastroenterology & Endoscopy News. https://www.gastroendonews.com/In-the-News/Article/12-19/Hand-Held-Stimulator-Shows-Promise-in-Gastroparesis/56703