Effectiveness and Safety of Hwangchil–Unripe Bokbunja Extract Mixture on Blood Pressure: A Randomized Double-Blind Placebo-Controlled Clinical Trial

From 25% to 50% of adults are affected by prehypertension. Prehypertension increases the risk of hypertension and affects the heart and systemic vascular system. Food mixed tree essence of Dendropanax morbifera called Hwangchil in Korean and immature fruit of Rubus coreanus, called Bokbunja (HDR-2), have been studied for safety and effectiveness against prehypertension studies. This study was a randomized double-blind placebo-controlled multicenter clinical trial lasting 19 months from October 2017 to May 2019. The 88 subjects who enrolled in the study were divided into two groups. The treatment group was provided HDR-2 and the other group took a placebo. Both HDR-2 and placebo were in the form of capsules, and the dose was 900 mg per day. Subjects took HDR-2 or placebo capsules once a day for 8 weeks before dinner. The primary observational indicators were systolic blood pressure (SBP) and diastolic blood pressure (DBP), and the secondary observational indicators were mean arterial pressure (MAP), mean pulse pressure, pulse rate, angiotensin-converting enzyme activity, renin activity, aldosterone, and highly sensitive-C reactive protein. The number of measurements was three times: the first visit in the screening week, the second visit in 4 weeks, and the third visit was after 8 weeks. Significant study results showed that the SBP and MAP of the HDR-2 group after 8 weeks were lower than those of the placebo group. Adverse events were not significantly different between the two groups. In conclusion, these results suggest that HDR-2 may be a useful intervention for the management of prehypertension. The protocol was registered in the Korean Clinical Trial Registration system (http://cris.nih.go.kr; registration number: KCT0004300).