Pharmacokinetic comparison of a generic coenzyme Q₁₀ solubilizate and a formulation with soybean phytosterols

Coenzyme Q₁₀ (CoQ₁₀) is essential for all cells, and deficiency has been implicated in cardiovascular disease. Plant phytosterols inhibit cholesterol absorption, and may thereby also reduce cardiovascular risk. This study compared the relative bioavailability of CoQ₁₀ solubilized in low-dose soybean phytosterols (SterolQ₁₀) with a generic CoQ₁₀ solubilizate. In a randomized, cross-over design, 36 healthy males received a single 100 mg dose of CoQ₁₀, as SterolQ₁₀ or generic CoQ₁₀, with a two-week washout between treatments. Plasma CoQ₁₀ was analysed at baseline, and at 2, 4, 6, 8 and 10 h after supplement ingestion. Subjects were then administered either 100 mg/day of generic CoQ₁₀ or SterolQ₁₀ for 4 weeks. Fasting plasma CoQ₁₀ levels were measured at baseline and following supplementation. The two preparations were bioequivalent in regard to the area under the curve (AUC(0-10h) ) and maximum increase in concentration (C(max) ), with geometric mean ratios of 0.89 (CI 0.81-0.98) and 0.88 (CI 0.80-0.96), respectively. Four-weeks of CoQ₁₀ resulted in a comparable twofold increase in CoQ₁₀ levels for both formulations (p < 0.001), which was similar between preparations (p = 0.74). The combined CoQ₁₀ and phytosterol formulation, SterolQ₁₀, showed bioequivalence to the generic CoQ₁₀ following a single CoQ₁₀ dose, and demonstrated comparable bioavailability following multiple dose administration.