Efficacy and Safety of Ginkgo Biloba Dropping Pills in the Treatment of Coronary Heart Disease with Stable Angina Pectoris and Depression: Study Protocol for a Randomised, Placebo-Controlled, Parallel-Group, Double-Blind and Multicentre Clinical Trial.

Background Coronary heart disease(CHD) with stable angina pectoris is a common cardiovascular disease. It has been reported that 10%-81.4% of these patients suffer from psychological conditions,such as depression, which has been associated with more frequent angina, lower treatment satisfaction and lower perceived quality of life. Ginkgo biloba extract (GBE), the raw material of Ginkgo biloba dropping pills (GBDPs), is widely used to treat various conditions, including cardiovascular disease, ischaemic cerebrovascular disease, and depression. This clinical trial aimed to examine the efficacy and safety of GBDPs in improving the frequency of angina pectoris and the life quality of patients with stable angina pectoris and depression symptoms. Methods This randomised, double-blind, placebo-controlled, parallel-group and multicentre clinical trial will be conducted in four medical centres in China. We aim to recruit approximately 72 participants aged 18-75 years with depression and coronary heart disease with stable angina pectoris. Based on conventional drug treatment, participants will be randomly assignedto the treatment group (GBDPs group; n=36) or the control group (placebo group; n=36) at a 1:1 allocation ratio. After randomisation,follow-up will be done at 4 weeks, 8 weeks and 12 weeks (+/- 3 days). Additionally, 30 healthy individuals will be enrolled to investigate the underlying pharmacological mechanisms of the effects of GBE. The primary outcomes will be the Seattle Angina Questionnaire score and the frequency of angina pectoris-related symptoms each week. The secondary outcomes will include the 36-item Short Form Health Survey quality-of-life scale, Hamilton Depression Scale and composite endpoint incidence of major adverse cardiovascular events. Ethics and dissemination This trial has been approved by the Research Ethics Committee of the First Affiliated Hospital of Guangzhou University of Chinese Medicine, China (approval number: ZYYECK [2020]030). Written informed consent will be obtained from all participants. The results of this trial will be publicly shared through academic conferences and peer-reviewed journals.