Chinese Herbal Formula Xuefu Zhuyu for Stable Angina (CheruSA): Study Protocol for a Multicenter Randomized Controlled Trial

Introduction. Stable angina (SA) in coronary heart disease is a common ischemic heart disease endangering the patient's quality of life and longevity. Clinical trials have demonstrated that the Chinese herbal formula Xuefu Zhuyu (XFZY) has benefits for SA patients. However, there remains a lack of high-quality evidence to support clinical decision-making. Therefore, we designed a randomized controlled trial (RCT) to evaluate the efficacy and safety of XFZY for SA. Methods and Analysis. This multicenter, double-blinded RCT will be conducted in China. 152 eligible participants will be randomly assigned to either an XFZY group or a control group at a 1 : 1 ratio. Participants in the XFZY group will receive XFZY plus routine care, while those in the control group will receive placebo plus routine care. The study period is 26 weeks, including a 2-week run-in period, a 12-week treatment period, and a 12-week follow-up. The primary outcome is the change in visual analogue scale score for angina pain intensity from baseline to 12 weeks. The secondary outcomes are the angina attack frequency and duration, the nitroglycerin dosage consumed, the Canadian Cardiovascular Society grading of effort angina, the Seattle Angina Questionnaire, the EuroQol-5-Dimensions-5-Level, the incidence of major adverse cardiac events, health cost evaluation, and overall assessment for study drugs. Ethics and Dissemination. The study has been approved by the ethics committee of Guangdong Provincial Hospital of Chinese Medicine (approval no. BF2019-175-01). Results will be submitted for publication in peer-reviewed journals and disseminated at scientific conferences. This trial is registered with ChiCTR1900026899, registered on 26 October 2019.