An interventional study of Ubiquinol and Ubiquinone in Borderline High LDL-cholesterol, sponsored by SF Research Institute, Inc.. Not yet recruiting at 1 site in United States. Open to participants aged 35 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-10-19.
Sponsored by SF Research Institute, Inc. · Not applicable, Interventional, and Treatment
This randomized, double-blind, placebo-controlled clinical trial will evaluate the effects of Ubiquinol and Ubiquinone on vascular endothelial function in generally healthy adults with borderline high LDL-cholesterol. Participants will receive Ubiquinol 200 mg/day, Ubiquinone 200 mg/day, or placebo for 8 weeks. The primary outcome is change in flow-mediated dilation (FMD), a measure of vascular endothelial function, assessed at baseline, Week 4, and Week 8. The study will also evaluate changes in plasma CoQ10 levels, nitric oxide, LDL oxidation susceptibility, oxidative stress markers, and treatment-emergent adverse events.
This randomized, double-blind, placebo-controlled, parallel-group clinical trial is designed to evaluate and compare the effects of reduced CoQ10 (Ubiquinol) and oxidized CoQ10 (Ubiquinone) on vascular endothelial function in generally healthy adults with borderline high LDL-cholesterol.
Coenzyme Q10 (CoQ10) exists in two interconvertible forms, reduced CoQ10 (Ubiquinol) and oxidized CoQ10 (Ubiquinone). The study is designed to determine whether Ubiquinol provides a superior effect on vascular endothelial function compared with Ubiquinone and placebo. Vascular endothelial function will be assessed using brachial artery flow-mediated dilation (FMD), a non-invasive measure of endothelial function.
A total of 120 eligible participants will be enrolled and randomized in a 1:1:1 ratio to one of three treatment groups: Ubiquinol 200 mg/day, Ubiquinone 200 mg/day, or identical placebo. Participants will take two soft capsules once daily for 8 weeks, preferably after breakfast or lunch containing fat, with water or warm water.
The study population will consist of generally healthy males aged 35-65 years and post-menopausal females up to 65 years of age, with a BMI of 18.5-29.9 kg/m² and borderline high LDL-cholesterol between 100 and 159 mg/dL. Eligible participants will also have a screening FMD value between 2.5% and 6.0% and no current acute or uncontrolled chronic illness.
Study assessments will be performed at baseline, Week 4, and Week 8. The primary endpoint is the change in FMD from baseline through Week 4 and Week 8. Secondary assessments will include changes in plasma CoQ10 levels, including total, reduced (Ubiquinol), and oxidized (Ubiquinone) CoQ10 concentrations and the reduced-to-total CoQ10 ratio. Additional secondary assessments will include plasma nitric oxide measured through nitrite/nitrate quantification, LDL oxidation susceptibility, and oxidative stress markers including malondialdehyde (MDA), oxidized LDL (oxLDL), and total antioxidant capacity (TAC).
Safety will be evaluated throughout the 8-week study by assessing treatment-emergent adverse events (TEAEs) and treatment-emergent serious adverse events (TESAEs).
The primary objective is to evaluate the superiority of reduced CoQ10 (Ubiquinol) over oxidized CoQ10 (Ubiquinone) in improving vascular endothelial function as measured by FMD. The study will also generate scientific evidence regarding the effects of the two forms of CoQ10 and collect mechanistic and biomarker data that may support future structure/function claims and related scientific and commercial applications.
SF Research Institute, Inc. is the lead sponsor of 20 studies on the registry; 12 are open to participants now.
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Exclusion Criteria:
Participants will receive Ubiquinol 200 mg/day, administered orally as two soft capsules once daily for 8 weeks. Participants will be instructed to take the capsules with water or warm water after breakfast or lunch containing fat.
Dietary Supplement: Ubiquinol
Participants will receive Ubiquinone 200 mg/day, administered orally as two soft capsules once daily for 8 weeks. Participants will be instructed to take the capsules with water or warm water after breakfast or lunch containing fat.
Dietary Supplement: Ubiquinone
Participants will receive identical placebo soft capsules orally as two capsules once daily for 8 weeks, according to the study randomization schedule.
Other: Placebo
Ubiquinol 200 mg/day, administered orally as two soft capsules once daily for 8 weeks. Participants will be instructed to take the capsules with water or warm water after breakfast or lunch containing fat.
Ubiquinone 200 mg/day, administered orally as two soft capsules once daily for 8 weeks. Participants will be instructed to take the capsules with water or warm water after breakfast or lunch containing fat.
Identical placebo soft capsules administered orally as two capsules once daily for 8 weeks according to the study randomization schedule.
Change in Flow-Mediated Dilation (FMD)
Change in Flow-Mediated Dilation (FMD), a measure of vascular endothelial function.
Time frame: Baseline, Week 4, Week 8
Change in Total Plasma CoQ10 Concentration
Change from baseline in the absolute concentration of total coenzyme Q10 (CoQ10) in plasma, measured in μg/mL.
Time frame: Baseline, Week 4, Week 8
Change in Plasma Ubiquinol Concentration
Change from baseline in the absolute concentration of reduced coenzyme Q10 (ubiquinol) in plasma, measured in μg/mL.
Time frame: Baseline, Week 4, Week 8
Change in Plasma Ubiquinone Concentration
Change from baseline in the absolute concentration of oxidized coenzyme Q10 (ubiquinone) in plasma, measured in μg/mL.
Time frame: Baseline, Week 4, Week 8
Change in Ratio of Reduced to Total CoQ10
Change from baseline in the ratio of reduced CoQ10 (ubiquinol) to total CoQ10 in plasma.
Time frame: Baseline, Week 4, Week 8
Change in Plasma Nitric Oxide (NO)
Change from baseline in plasma nitric oxide (NO), assessed by nitrite/nitrate quantification.
Time frame: Baseline, Week 4, Week 8
Change in LDL Oxidation Susceptibility
Change from baseline in LDL oxidation susceptibility, measured as lag time using a copper-induced assay.
Time frame: Baseline, Week 4, Week 8
Change in Malondialdehyde (MDA) Levels
Change from baseline in serum levels of malondialdehyde (MDA), an oxidative stress marker.
Time frame: Baseline, Week 4, Week 8
Change in Oxidized LDL (oxLDL) Levels
Change from baseline in serum levels of oxidized low-density lipoprotein (oxLDL), an oxidative stress marker.
Time frame: Baseline, Week 4, Week 8
Change in Total Antioxidant Capacity (TAC)
Change from baseline in serum total antioxidant capacity (TAC).
Time frame: Baseline, Week 4, Week 8
Treatment-Emergent Adverse Events
Number and proportion of Treatment-Emergent Adverse Events (TEAEs).
Time frame: Baseline, Week 4, Week 8
Treatment-Emergent Serious Adverse Events
Number and proportion of Treatment-Emergent Serious Adverse Events (TESAEs).
Time frame: Baseline, Week 4, Week 8
Plan to share: No
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From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drugs tested here: Ubiquinol · Coenzyme Q10
SF Research Institute, Inc.