SAN ANTONIO – Oral supplementation with a proprietary blend of human milk oligosaccharides improved all of the core symptoms of irritable bowel syndrome in a large open-label study, Magnus Simren, MD, PhD, reported at the annual meeting of the American College of Gastroenterology.
Bruce Jancin/MDedge News
Dr. Magnus Simren
The human milk oligosaccharides (HMOs) were well tolerated, too. Only 2.5% of 317 study participants at 17 U.S. sites discontinued the 12-week study because of side effects, which consisted of flatulence and other mild gastrointestinal symptoms, noted Dr. Simren, a gastroenterologist and professor of medicine at the University of Gothenburg (Sweden).
These positive study results are consistent with the notion that an altered gut microbiota plays a pathophysiological role in irritable bowel syndrome (IBS).
“The challenge is to identify suitable interventions that restore intestinal microbiota composition and functioning,” Dr. Simren observed.
Oral HMOs show promise as one such intervention. In prior small proof-of-concept studies, Dr. Simren and his coworkers demonstrated that HMOs increased gut levels of Bifidobacteria, which are microorganisms important to a healthy gut and are depleted in IBS. The investigators also established that HMOs increased levels of metabolites essential for the gut’s barrier and immune functions.
HMOs are the third-largest constituent in human breast milk. Interest in their potential therapeutic application in IBS grew out of earlier pediatric work demonstrating that HMOs are of great importance in infant health: They bind pathogens and promote gut barrier maturation and immune function.
Dr. Simren reported on 317 patients who met Rome IV criteria for IBS. Nearly two-thirds of them had severe IBS based upon an IBS–Symptom Severity Score above 300. Another third had moderate IBS. Subjects were instructed to take 5 g/day of a 4:1 mix of the HMOs 2’-fucosyllactose and lacto-N-neotetraose, a proprietary nutritional support product available over the counter as Holigos. Participants remained on stable background medications throughout the 12-week study, during which they were evaluated every 4 weeks.
The primary outcome was the effect of daily oral consumption of HMOs on stool consistency as assessed using the Bristol Stool Form Scale. At baseline, 50.3% of subjects had IBS constipation as defined by Bristol type 1-2 stools. By week 4, the proportion of patients with constipation dropped to 32.9%, and at weeks 8 and 12, just under 31%. Similarly, the proportion of patients with diarrhea as reflected in Bristol type 6-7 stools quickly improved from 40.4% at baseline to 27.5% at week 4 and 26% thereafter. Meanwhile, the proportion of patients with normal stools on the Bristol scale jumped from 9.3% at baseline to 39.6% at week 4 and nearly 43% thereafter.
About 77% of patients reported a significant reduction in symptom severity within 4 weeks, and 87% did so by 12 weeks. Bloating decreased by 59%, as did abdominal pain severity. In addition, scores on the IBS Quality of Life Scale improved by 48%.
The observed improvements in symptoms and quality of life were consistent across all IBS subtypes.
“Of course, the next step now is to perform a randomized, placebo-controlled, double-blind study to see if these encouraging results can be confirmed in that setting,” Dr. Simren commented.
Session comoderator Brooks D. Cash, MD, of the University of Texas, Houston, called the HMO study “very provocative” and declared he is looking forward to the randomized, controlled trial, which he hopes will assess the long-term durability of the treatment benefits. That trial is still in the planning stages.
Dr. Simren reported serving on an advisory board for Glycom, the Danish company which markets Holigos and sponsored the open-label U.S. study.