Xuan Bai Cheng Qi formula as an adjuvant treatment of acute exacerbation of chronic obstructive pulmonary disease of the syndrome type phlegm-heat obstructing the lungs: a multicenter, randomized, double-blind, placebo-controlled clinical trial

BACKGROUND Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is a common cause of morbidity and mortality. Traditional Chinese medicine (TCM) is used to treat AECOPD as adjunctive therapy. This study aimed to evaluate the efficacy and safety of the TCM formula Xuan Bai Cheng Qi as an adjuvant therapy for AECOPD patients with the syndrome type of phlegm-heat obstructing the lungs. METHODS A multicenter, randomized, double-blind, placebo-controlled clinical trial was conducted. A total of 244 patients were divided into the intervention group (n = 122, treated with conventional medicine and Xuan Bai Cheng Qi) and the control group (n = 122, treated with conventional medicine and placebo). Total symptom scores (cough, phlegm, wheezing, chest congestion) before treatment and at 3, 5, 7, 10 days post-treatment were recorded. Lung function, arterial blood gas, serum inflammatory cytokines, oxidation/anti-oxidation index were observed before treatment and at the end of the 10-day treatment. RESULTS A total of 242 patients completed the study. The full analysis set (FAS) population was 244 and the per-protocol analysis set (PPS) population was 229. After the 10-day treatment, symptom scores of the Xuan Bai Cheng Qi group were significantly lower over time compared with the control group (FAS: mean difference -1.84, 95% CI -2.66 to -1.03, P < .001; PPS: mean difference -1.87, 95% CI -2.71 to -1.03, P < .001). FEV1, FVC, and FEV1%pred were significantly higher over time in the Xuan Bai Cheng Qi group compared with those in the control group (day 10, FAS and PPS: P < .05). PaO2 and PaCO2 were significantly improved in the Xuan Bai Cheng Qi group (day 10, FAS and PPS: P < .05). Xuan Bai Cheng Qi was also found to ameliorate cytokine levels and oxidation/antioxidant index compared with placebo. There were no differences in safety variables and adverse events between the two groups. CONCLUSIONS Xuan Bai Cheng Qi formula appears to be a safe and beneficial treatment for AECOPD of phlegm-heat obstructing the lungs syndrome type.