Study protocol for a randomized controlled trial: Qiliqiangxin in heart failUre: assESsment of reduction in morTality (QUEST)

Background: Qiliqiangxin (QLQX) capsule is a Traditional Chinese Medicine (TCM) that has been approved in China for the treatment of chronic heart failure (CHF). Our previous study showed with a background of standard HF treatment, QLQX capsules further reduced the levels of NT-proBNP and the incidence of composite cardiac events (CCEs) in CHF patients. This study aims to further assess the reduction in mortality when using QLQX compared with placebo for heart failure with reduced ejection fraction (HFrEF) patients. Methods: This study is a randomized, double-blind, placebo-controlled, parallel-group, multi-center, event-driven clinical study of approximately 3080 patients for a targeted 620 events. Patients must have a diagnosis of heart failure for at least 3 months prior to screening. Patients will be randomized 1:1 to receive the placebo or QLQX in addition to their standard medications of CHF. The primary efficacy outcome event is a composite cardiovascular death and re-hospitalization due to the worsening of heart failure. Discussion: The QUEST study is a randomized control study of TCM in chronic heart failure. It will determine the place of QLQX as an new treatment approach and provide additional and innovative information regarding TCM - and the specific used of QLQX in HFrEF.