Ruanjian Qingmai Granules for the Treatment of Early Symptomatic Peripheral Arterial Disease: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Clinical Trial Protocol

Purpose: Peripheral arterial disease (PAD) is a chronic ischemic disease caused by atherosclerosis of the lower extremities, with early clinical symptoms manifesting mainly as intermittent claudication. Current treatment of PAD is based on the control of cardiovascular risk factors. However, even vasoactive drugs are not ideal for improving ischemic symptoms in the lower limbs of PAD patients. Ruanjian Qingmai granules, derived from the classic formula of the late Professor Jiuyi Xi, a famous traditional Chinese medicine doctor in Shanghai, have good clinical efficacy in the treatment of the pattern of blood vessel stasis and obstruction of PAD and have been used by more than 600,000 PAD patients over the past three decades. This study aims to evaluate the efficacy and safety of Ruanjian Qingmai granules in patients with symptomatic PAD. Patients and methods: A prospective, center-randomized, double-blind, placebo-controlled clinical trial will be conducted at 9 grade A tertiary hospitals in Shanghai. It is anticipated that 250 patients with early symptomatic PAD will be recruited and randomized to the control and intervention groups (1:1 ratio of central randomization). Subjects will be treated with Ruanjian Qingmai granules or placebo at 6 g twice daily for 16 weeks. The primary efficacy indicators are the pain-free walking distance and maximum walking distance. The secondary efficacy indicators are the ankle-brachial index, walking impairment questionnaire, quality of life score, and Chinese medicine syndrome score. Conclusion: Positive results from this study will demonstrate the efficacy and safety of Ruanjian Qingmai granules in improving ischemic symptoms in patients with symptomatic PAD.