摘要Background:Mesalazine preparations serve as first-line therapy for active mild-to-moderate ulcerative colitis(UC),however,not all patients respond to mesalazine.Patients with mesalazine-refractory UC often switch to corticosteroids,immunological therapy,and biological agents,but their use is limited owing to their well-characterised side effects(e.g.osteoporosis and cushingoid feature).Therefore,there is an unmet medical need for novel treatments with a manageable safety profile for patients with mesalazine-refractory UC.New Wumei Pill is a novel and effective herbal prescription for the treatment of UC,and our preliminary study suggested that New Wumei Pill has a significant effect on patients with mesalazine-refractory UC.However,its effectiveness and safety has not been evaluated convincingly.Objectives:This trail aims to evaluate efficacy,safety and mechanisms of New Wumei Pill in the treatment of patients with mesalazine-refractory UC.Methods:This is a prospective,randomized,double-blind control trial,in which 72 patients with mesalazine-refractory mild-to-moderate UC will be randomized in a 1:1 ratio in the treatment and control group.Patients will be screened for eligibility at the outpatient and ward of the Department of Gastroenterology in Dongfang Hospital,Beijing University of Chinese Medicine.72 participants will undergo strict screening to meet the diagnostic criteria of mildly to moderately active UC,with modified Mayo score of 3-10 points.All patients will be administered by mesalazine enteric-coated tablets for 8 weeks,at the same time,the patients in treatment group will receive New Wumei Pill,while patients from control group will be administered by dummy New Wumei Pill.Results:The primary outcomes are clinical efficacy rate and clinical remission rate according to the modified Mayo score.The secondary outcomes are individual symptom score,TCM syndrome score,endoscopic response rate,mucosal healing rate,and quality of life scale score.Finally,biological samples from participants will be preserved to reveal the mechanisms of New Wumei Pill on UC.Conclusions:We hypothesize that the patients with mesalazine-refractory mild-to-moderate UC will benefit from New Wumei Pill.If successful,this trial will provide evidence of traditional Chinese medicine in the treatment of UC,and hold promises for novel options UC patients and policymakers.