Effects of an optimized beta-glucan–based formulation on symptoms, functional capacity, and systemic inflammation in patients with COPD: a randomized controlled trial

Background Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow limitation, chronic inflammation, and oxidative stress, leading to progressive functional impairment and reduced quality of life. Beta-glucan possesses immunomodulatory and anti-inflammatory properties, but its therapeutic potential in COPD remains poorly defined. This study aimed to optimize a combined formulation of beta-glucan, broccoli extract, and quercetin (Pro β-Glucan+) through in vitro evaluation and to investigate its clinical efficacy in patients with stable COPD. Methods HFL1 lung fibroblasts were treated with different ratios of Pro β-Glucan+®, and cell viability and wound healing assays were performed to identify the optimal formulation. The selected ratio was evaluated in a 12-week randomized, double-blind, placebo-controlled trial. A total of 42 participants were randomized, of whom 38 completed the study and were included in the final analysis (Pro β-Glucan+, n = 19; placebo, n = 19). Prespecified primary outcome was FEV 1 . Secondary outcomes included clinical symptoms, functional capacity, health status, inflammatory and oxidative stress biomarkers, and patient satisfaction. Results The 10:3:2 ratio (beta-glucan:broccoli extract:quercetin) significantly enhanced HFL1 cell cell viability and wound healing activity among the tested formulations and was selected for clinical evaluation. Pro β-Glucan+® was well tolerated and associated with within-group improvements in dyspnea, respiratory symptoms, functional capacity, and health status after 12 weeks, with significant between-group differences in mMRC and CAT scores at week 12. No significant within- or between-group difference was observed in the prespecified primary outcome, FEV 1 , or in systemic inflammatory and oxidative stress biomarkers. Patient satisfaction was higher with Pro β-Glucan+® than with placebo. Conclusion The optimized Pro β-Glucan+® formulation demonstrated in vitro biological activity and was associated with improvements in several clinical outcomes in patients with stable COPD. Significant between-group differences were observed in mMRC and CAT scores at week 12. These findings support further investigation of this combination as an adjunctive nutritional intervention for COPD management. Clinical Trial Registration https://clinicaltrials.gov/study/NCT05878834 , identifier NCT05878834.