Efficacy and Safety of Guben Kechuan Granules in the Treatment of Chronic Bronchitis: A Multi-Center and Randomized Controlled Trial

Background: Chronic bronchitis (CB) is an inflammatory respiratory disease characterized by high prevalence and treatment challenges. In recent years, the integration of traditional Chinese medicine (TCM) with conventional therapies has gained widespread application in CB management, showing promising clinical benefits. Methods: This multicenter, randomized controlled trial, led by China-Japan Friendship Hospital in Beijing, China, enrolled 300 CB patients aged 18-75 years. Participants were randomized (2:2:1) into three groups: Guben Kechuan Granules (experimental group, n=120), Guilong Kechuanning Capsules (positive drug control, n=120), and subject education (blank control, n=60). The treatment lasted 24 weeks, followed by a 24-week follow-up. Efficacy was assessed through symptom evaluation, acute exacerbation of CB (AECB) incidence, pulmonary function tests, immunological assessments, and quality of life measures. Safety was evaluated based on adverse event reporting. Data analysis was conducted using SAS 9.4 software. Results: Of the enrolled patients, 299 participants (99.7%) completed the full analysis, 298 were included in the safety assessment, and 278 entered the per-protocol efficacy analysis. Compared to the blank control group, Guben Kechuan Granules significantly reduced the time to first AECB, as well as the duration, severity, and frequency of AECB episodes (all p<0.05). After 24 weeks of treatment, symptom scores for cough (-21.85 +/- 19.73), expectoration (-22.74 +/- 18.66), and wheezing (-21.33 +/- 18.76) showed substantial improvement (p<0.05). These benefits persisted throughout the 24-week follow-up (p<0.05). Additionally, significant improvements were observed in mobility, self-care, daily activities, and overall health status in the experimental group (all p<0.05). However, no significant changes were observed in lung function parameters-including FEV1/FVC%, FEV1%pred, PEF, MMEF, FVC, or FEV1-across all three groups after 24 weeks of treatment. No serious adverse events were reported in the experimental group during follow-up. Conclusion: Guben Kechuan Granules demonstrated significant efficacy and safety in CB management, alleviating clinical symptoms, reducing AECB incidence and severity, and enhancing patients' quality of life.