A Randomized, Double-blind, Placebo-controlled, Multicenter Clinical Study of Chuanzhi Tongluo Capsule in Acute Ischemic Stroke (CONCERN): Study Rationale and Design

Abstract Background: Acute ischemic stroke (AIS) remains a significant cause of disability worldwide. Current treatments, primarily intravenous thrombolysis (IVT), are limited by narrow time windows and reperfusion injury, leading to suboptimal outcomes for many patients. Chuanzhi Tongluo (CZTL), a traditional Chinese medicine, has been preliminarily recognized as a novel cerebral protection agent in animal models. Objectives: This trial investigates the efficacy and safety of CZTL capsule in patients with AIS who are not eligible for IVT or who experience early neurological deterioration after IVT. Methods and design: The CONCERN trial is an investigator-initiated, prospective, multicenter, double-blind, parallel-control, randomized clinical study in China. An estimated 1,208 eligible participants will be consecutively randomized to receive CZTL capsule therapy or placebo in 1:1 ratio across approximately 70 stroke centers in China. All enrolled patients are orally administered 2 capsules of CZTL or placebo 3 times a day together with antiplatelet agents for 3 months. Outcomes: The primary endpoint is an excellent functional outcome, defined as a score of 0 or 1 on the mRS at 90 days. Lead safety endpoints included 90-day mortality and symptomatic intracranial hemorrhage within 48 hours. Conclusions: Results of CONCERN trial will determine the clinical efficacy and safety of the traditional Chinese medicine CZTL capsule in the treatment of AIS patients. Trial registry number: ChiCTR2300074147 (www.chictr.org.cn).