‘Sporebiotics’ reduce FD symptoms

Spore-forming probiotics, otherwise termed “sporebiotics”, may help reduce post-prandial gastrointestinal (GI) symptoms such as bloating and epigastric pain in individuals with functional dyspepsia (FD), says an expert at DDW 2021.

FD is one of the most common functional GI disorders. “Patients complain of upper abdominal symptoms with no structural explanation,” said lead author Dr Lucas Wauters from University Hospitals Leuven in Leuven, Belgium.

The Rome III consensus characterized FD into postprandial distress syndrome (PDS), with onset or worsening of symptoms after a meal, and epigastric pain syndrome (EPS, with meal-unrelated symptoms such as epigastric pain or burning.

Acid suppression with proton pump inhibitors (PPIs) is the current first-line option for FD. However, PPIs have limited long-term efficacy and may cause dysbiosis, which could be prevented with probiotics. The Bacilli class – B. coagulans and B. subtilis, in particular – is a promising option because it produces gastric-resistant endospores, has a long shelf-life, and survives well in the small intestine, Wauters said.  

“However, the efficacy and safety of these spore-forming probiotics have not been studied in FD relative to PPI,” he added.

A closer look at sporebiotics

To test if sporebiotics offer benefits that are different from PPI therapy, Wauters and his team randomly assigned 68 patients with FD, who were on or off PPI therapy, to 2.5 x 10⁹ CFU*/capsule of B. coagulans MY01 and B. subtilis MY02 twice daily for 8 weeks, or a matching placebo. This was followed by an open-label regimen of the same sporebiotics for 8 more weeks.

A 14-glycocholic acid breath test was used to detect small intestinal bacterial overgrowth in patients on PPI therapy at baseline and after 8 weeks. The Leuven Postprandial Distress Scale (LPDS) score was used to calculate early satiation, postprandial fullness, and upper abdominal bloating, as well as epigastric pain syndrome.

PDS, EPS reduced

The primary outcome of a change in PDS of >0.7 from baseline to week 8 was achieved in 48 percent of patients taking sporebiotics vs 20 percent of those taking placebo.  Among patients on PPIs, the primary outcome was achieved in 46 percent vs 13 percent, respectively. For patients not taking PPIs, the values were 50 percent and 27 percent, respectively.

At 8 weeks, the change in PDS score was significantly greater with sporebiotics vs placebo, so was the reduction in EPS; p<0.05 for each). PDS score also dropped in patients switched to open-label sporebiotics. The reduction was sustained in the original sporebiotic group.

When PDS and EPS scores were broken down into individual components, sporebiotics were also associated with significantly greater improvements in cardinal postprandial distress, cardinal epigastric pain, postprandial fullness, and upper abdominal pain.

Bacterial overgrowths improved

Among patients taking PPIs, baseline rates of positivity for bile acid breath testing were similar for sporebiotics and placebo (18 percent and 25 percent, respectively; p= 0.29). At 8 weeks, only 7 percent of patients taking sporebiotics tested positive on their breath test vs 36 percent of those taking placebo; p=0.04). “This suggests improvements in small intestinal bacterial overgrowth,” said Wauters.

After 16 weeks of sporebiotics use, systemic interleukin (IL)-17A levels and T helper (Th)17 cells dropped. A reduction in gut-homing Th17 and Th2 cells was also noted for PPI users. Interestingly, sporebiotic efficacy was associated with a reduction in Th17 signaling.

Adverse events (AEs) were higher in the placebo group (33 percent vs 16 percent for sporebiotics) so were GI-specific AEs (15 percent vs 3 percent, respectively).  

Take-away message

“Compared with placebo, the combination of B. coagulans and B. subtilis was effective and safe in FD, with a reduction in PDS, EPS, and individual symptom scores,” said Wauters. “Sporebiotics could be considered in combination with PPIs, or as monotherapy, in patients with persistent symptoms.”