Efficacy and Safety of Bacillus clausii UBBC-07 in chronic kidney disease: a double-blind randomized placebo-controlled study

Abstract

Chronic kidney disease (CKD) is a progressive disorder characterized by declining renal function, systemic inflammation, oxidative stress, and accumulation of gut-derived protein-bound uremic toxins. The gut–kidney axis has emerged as a therapeutic target, and probiotics may offer a supportive adjunct approach. This study evaluated the efficacy and safety of Bacillus clausii UBBC-07 supplementation in patients with stage III–IV CKD. In this randomized, double-blind, placebo-controlled trial, participants received either Bacillus clausii UBBC-07 (2 × 10⁹ CFU/day; two capsules) or matching placebo for six months. Primary outcomes included changes in protein-bound uremic toxins, renal function markers, inflammatory and oxidative stress biomarkers, electrolyte profiles, and health-related quality of life (SF-8), with safety assessed through adverse event monitoring. Compared to placebo, UBBC-07 significantly reduced key protein-bound uremic solutes, including p-cresyl sulfate (PCS), indole-3-acetic acid (IAA), and indoxyl sulfate (IS). UBBC-07 also demonstrated significant reductions in systemic inflammatory biomarkers and improvement in oxidative stress parameters, reflected by decreased lipid peroxidation and enhanced endogenous antioxidant activity. Renal metabolic indices improved with significant reductions in blood urea nitrogen (p = 0.001) and uric acid (p < 0.0001), along with a significant increase in eGFR (p < 0.05). Electrolyte levels remained stable. SF-8 scores improved significantly at Visits 4 and 5, indicating enhanced quality of life. UBBC-07 was well tolerated, with only mild, self-limiting adverse events and no treatment discontinuations. Overall, Bacillus clausii UBBC-07 appears to be a safe adjunct therapy in stage III–IV CKD, warranting further evaluation in larger studies.