Efficacy and Safety of Tuo-Min-Ding-Chuan Decoction on Mild Allergic Asthma: Study Protocol for a Randomized, Double-Blind, Placebo-Controlled, Parallel-Group, Single-Center Trial

Abstract Background: Allergic asthma (AA) is a common asthma phenotype. The variable and recurrent clinical symptoms cause a lot of pain to the patients, but there is no complete cure for the disease. It is worth noting that traditional Chinese medicine (TCM) has some advantages in the treatment of AA. Tuo-Min-Ding-Chuan Decoction (TMDCD) is an effective prescription from Professor Wang Qi, academician of the Chinese Academy of Engineering and master of Chinese medicine. Our previous studies with animal experiment have proved the efficacy of decoct TMDCD. Therefore, we designed a clinical trial to evaluate the safety and efficacy of TMDCD in the treatment of mild AA. Methods: This study is a single-center, randomized, double-blinded, placebo-controlled, parallel-group trial. 324 subjects will be recruited and randomized in a 1:1 ratio in the Intervention and control groups. The Intervention group and control group will be administered TMDCD granules and placebo granules, respectively. The primary outcome measures are the total dose of budesonide-formoterol and Total Asthma Symptom Score(TASS). The secondary outcome measures include times of AA exacerbation, Asthma Control Test(ACT), The fraction of exhaled nitric oxide (FeNO), total IgE and allergen specific IgE, lung function testing, Blood routine, Constitution in Chinese medicine questionnaire (CCMQ), Asthma Quality of Life Questionnaire(AQLQ) and the total dose of cetirizine hydrochloride. The study period will last for 60 weeks, including 12 weeks for treatment time and 48 weeks for follow-up period. Discussion: We hypothesized that TMDCD might effectively relieve the symptoms of AA, reduce the number of relapses and the dosage of inhaled corticosteroids(ICS),and improve the quality of life of patients. Our hypothesis may be confirmed by the relevant data obtained in this study. Trial registration: This trial has been registered with the Chinese Clinical Trial Registry. Trial registration number: ChiCTR2200056239. Registered 2 February 2022. http://www.chictr.org.cn.