Exploration of the utility of different doses of Qingfei Dayuan granules: a multicenter, randomized, double-blind, placebo-controlled trial.

backgroundClinical studies have confirmed that Qingfei Dayuan (QFDY) granules are effective in the treatment of influenza and upper respiratory tract infections (URTIs) caused by pulmonary heat-toxin syndrome (PHTS). Granules of Chinese medicine formulations have become a widely used dosage form in clinical practice. With the continuous optimization of extraction technology, the advantages of Chinese medicine granules have been gradually demonstrated, but the price of Chinese medicine granules is generally higher than that of traditional dosage forms of Chinese medicine, and we support the rational use of the appropriate dosage of QFDY for patients with these conditions. Therefore, we set up half of the conventional dose as the low dose group, and designed the three-arm study to rigorously compare the efficacy difference of low-dose QFDY, QFDY and the placebo group, with the expectation of providing scientific support for the rational selection of the dose and the safe and effective use of the medicine in clinical practice.

methodsWe recruited 108 patients with clinical diagnoses of influenza and URTIs caused by PHTS to receive treatment at six hospitals in Hubei, China. Using a centralized randomization system, patients were randomly assigned at a 1:1:1 ratio to the QFDY, low-dose QFDY, or placebo control groups to receive the corresponding drug, and the study physicians, subjects, outcome assessors, and statisticians were unaware of group assignments. The primary outcome was the time to complete fever relief. Secondary outcomes included the efficacy of Chinese medicine in alleviating signs and symptoms and the disappearance rate of individual symptoms. Adverse events were monitored throughout the trial.

resultsA total of 108 patients were recruited. A total of 106 patients were included in the full analysis set (FAS). In the FAS analysis, there was no statistically significant difference in baseline of the three groups before treatment (P > 0.05). 1. Regarding the median time to complete fever relief, the QFDY, low-dose QFDY and placebo groups had median times of 26 h, 40 h and 48 h, respectively. The QFDY group had a shorter time to complete fever relief than the placebo group, and the difference was statistically significant (P < 0.05), while the low-dose QFDY group had a shorter time than the placebo group, but the difference was not statistically significant (P > 0.05). 2. In terms of the total efficacy of Chinese medicine in alleviating symptoms at the end of three full days of treatment, as well as the cure rate of red and sore throat, stuffy and runny nose, and sneezing, QFDY and low-dose QFDY were superior to the placebo, and the differences were statistically significant (P < 0.01). There was no statistical significance in the comparison between the QFDY group and the low-dose QFDY group (P > 0.05). 3. In terms of the headache cure rate after three full days of treatment, QFDY was superior to the placebo, with a statistically significant difference (P < 0.05), and there was no significant efficacy of low-dose QFDY. 4. Safety comparisons showed no serious adverse events and 30 minor adverse events, which were not clinically considered to be related to the drug and were not statistically significant.

conclusionsIn the treatment of patients with influenza and URTIs caused by PHTS, which are mainly characterized by clinical symptoms such as red and sore throat, stuffy and runny nose, and sneezing, when fever is not obvious or low-grade fever is present, the use of low-dose QFDY to simply alleviate the clinical symptoms is recommended and preferred. Moreover, with its good safety profile, QFDY can be used in the treatment of patients with influenza and URTIs caused by PHTS, which can effectively shorten the duration of fever, significantly increase the total efficacy of Chinese medicine in alleviating symptoms after 3 days of treatment, and accelerate the recovery of symptoms such as red and sore throat, stuffy and runny nose, sneezing, and headache, etc. Clinical Trial Registration: http://www.chictr.org.cn. TRIAL NUMBER: ChiCTR2100043449. Registered on 18 February 2021.