Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by recurrent abdominal pain associated with altered bowel habits in the absence of detectable structural abnormalities. Its pathophysiology is multifactorial and may involve alterations in the intestinal microbiota, impaired epithelial barrier function, low-grade immune activation, and disturbances in the digestion and fermentation of dietary nutrients.

Enzymax DuoBiotics combines digestive enzymes with a synbiotic formulation in a capsule-in-capsule delivery system. The outer capsule contains digestive enzymes intended for release in the stomach, whereas the inner capsule contains Lactobacillus plantarum and fructooligosaccharides intended for release in the intestine. This formulation is designed to separate the enzymatic and synbiotic components and support their delivery to the intended gastrointestinal sites. The combined approach is intended to support macronutrient digestion while modulating the intestinal microbial environment.

This randomized, double-blind, placebo-controlled, parallel-group study will compare once-daily Enzymax DuoBiotics with placebo over a 12-week treatment period in adults with IBS. Participants will be allocated in a 1:1 ratio, and treatment effects over time will be evaluated using assessments performed during the treatment period. The primary statistical analysis will use linear mixed-effects models including treatment group, time, and the treatment group-by-time interaction. The primary analysis will follow the intention-to-treat principle and may be supplemented by a per-protocol analysis.