Safety and efficacy of purified clinoptilolite-tuff treatment in patients with irritable bowel syndrome with diarrhea:Randomized controlled trial

BACKGROUND Irritable bowel syndrome(IBS)is a highly prevalent gastrointestinal disorder with poor response to treatment.IBS with predominant diarrhea(IBS-D)is accompanied by abdominal pain as well as high stool frequency and urgency.Purified clinoptilolite-tuff(PCT),which is approved by the Food and Drug Administration for use as a dietary supplement with the brand name G-PUR®,has previously shown therapeutic potential in other indications based on its physical adsorption capacity.AIM To assess whether symptoms of IBS-D can be ameliorated by oral treatment with PCT.METHODS In this randomized,placebo-controlled,double-blind pilot study,30 patients with IBS-D diagnosis based on Rome IV criteria were enrolled.Following a 4-wk run-in phase,14 patients were randomized to receive a 12-wk treatment with G-PUR®(2 g three times daily),and 16 patients received placebo.The relief from IBS-D symptoms as measured by the proportion of responders according to the Subject’s Global Assessment(SGA)of Relief was assessed as the primary outcome.For the secondary outcomes,validated IBS-D associated symptom questionnaires,exploratory biomarkers and microbiome data were collected.RESULTS The proportions of SGA of Relief responders after 12 wk were comparable in both groups,namely 21%in the G-PUR®group and 25%in the placebo group.After 4 wk of treatment,36%of patients in the G-PUR®group vs 0%in the placebo group reported complete or considerable relief.An improvement in daily abdominal pain was noted in 94%vs 83%(P=0.0353),and the median number of days with diarrhea per week decreased by 2.4 d vs 0.3 d in the G-PUR®and placebo groups,respectively.Positive trends were observed for 50%of responders in the Bristol Stool Form Scale.Positive trends were also noted for combined abdominal pain and stool consistency response and the Perceived Stress Questionnaire score.Only 64%in the G-PUR®group compared to 86%in the placebo group required rescue medication intake during the study.Stool microbiome studies showed a minor increase in diversity in the G-PUR®group but not in the placebo group.No PCT-related serious adverse events were reported.CONCLUSION In this randomized,double-blind,placebo-controlled study,the PCT product,G-PUR®,demonstrated safety and clinical benefit towards some symptoms of IBS-D,representing a promising novel treatment option for these patients.