Efficacy of Hwangryunhaedok-tang (Huang-lian-jie-du-tang, Oren-gedoku-to) for patients with hyperlipidemia: a study protocol for a randomized, double-blind, placebo-controlled, parallel, investigator-initiated clinical trial.

BACKGROUND: The prevalence of hyperlipidemia continues to increase due to aging and lifestyle changes. Statins are currently used as the first choice for treating hyperlipidemia, but are limited by adverse reactions. Hwangryunhaedok-tang (HHT) has received attention as a promising intervention for hyperlipidemia through a few experimental and clinical trials. This study aims to explore the feasibility, effectiveness, and safety of HHT for hyperlipidemia treatment. METHODS: This is a study protocol for a randomized, double-blind, placebo-controlled, parallel, investigator-initiated, pilot clinical trial held in Daejeon, Republic of Korea. Thirty patients with hyperlipidemia will be randomly allocated to HHT or placebo granule groups in equal proportions. Participants will be administered HHT or placebo granules three times per day for 8 weeks and followed up for another 4 weeks. The primary outcome is low-density lipoprotein cholesterol at 8 weeks from the commencement of treatment. Other blood lipid parameters, biomarkers of atherosclerosis, the degree of arteriosclerosis, blood glucose parameters, blood pressure, anthropometric parameters, health-related quality of life, and the changes in the general symptoms of cold and hot patterns will be measured as secondary outcomes. Adverse events and laboratory test results will be investigated to assess the safety. Changes in the gut microbiome before and after intervention will also be assessed as an exploratory outcome through next-generation sequencing. Data will be recorded in electronic case report forms and analyzed using SAS® Version 9.4. DISCUSSION: This is a rigorously designed pilot clinical trial to explore the effect and safety of Hwangryunhaedok-tang compared to placebo control for patients with hyperlipidemia, thereby potentially facilitating better management of hyperlipidemia. The results of this pilot study could form the foundation for a future large-scale, confirmatory clinical trial. TRIAL REGISTRATION: Clinical Research Information Service KCT0004564 . Registered on December 18, 2019.