Evaluation of Bacillus clausii Probiotic formulations in the Prevention of Antibiotic-Associated Diarrhea in Infants and Children: A Randomized, Double-Blind, Placebo-Controlled Study

Background & Objective: Antibiotic-associated diarrhea (AAD), is the most common side effect of antibiotics, affecting up to 30% of children receiving antibiotic treatment. We assessed the efficacy and safety of Sanzyme Biologics’ probiotic formulations of Bacillus clausii (B. clausii) in preventing AAD in children receiving antibiotics. Methods: This was a randomized, double-blind, placebo-controlled three-arm study conducted in children aged 6 months to 12 years old, with mild to moderate bacterial infections requiring β-lactam antibiotic treatment. Participants (N=90) were randomized 1:1:1 (30 per group) to receive either a multi-strain B. clausii probiotic [SNZCLB 1, SNZCLB 2, SNZCLB 3, SNZCLB 4 (B. clausii SNZ 1971)], a single-strain B. clausii SNZ 1971 probiotic, or a placebo, each at 2 billion CFU twice daily for up to 14 days along with antibiotic therapy. Results: The incidence of AAD was lower in the probiotic groups compared to the placebo group (2 [6.67%] in each probiotic arm, 6 [20.0%]), yielding a relative risk of 0.33 for both probiotic groups compared to placebo (P=0.20). Among participants who developed AAD (n=10), probiotic-treated children experienced significantly fewer diarrheal episodes in the first 24 hours (multi-strain vs. placebo: P=0.0111; single-strain vs. placebo: P=0.0419) and faster symptom resolution (multi-strain vs. placebo: P=0.0169). Gastrointestinal symptoms, including abdominal pain (P=0.6065) and nausea/vomiting (P=0.7836), were numerically lower in probiotic groups. Additionally, the mean total number of AAD episodes until resolution was significantly lower in the B. clausii groups as compared to placebo (multistrain B. clausii probiotic group vs placebo: P=0.0169; single-strain probiotic B. clausii group vs placebo: P=0.0639). Conclusion: Supplementation with either multistrain or single-strain B. clausii, along with β-lactam antibiotics, showed a favorable safety profile and reduced incidence of AAD and related gastrointestinal symptoms as compared to placebo. Sanzyme Biologics’ B. clausii probiotic formulations have shown comparable protective effects, supporting their use as adjunctive therapy from the first day of antibiotic treatment to prevent AAD.

Keywords : Antibiotic-Associated Diarrhea; Bacillus Clausii; Infants and Children; Probiotics;