This double-blind, randomized crossover study investigated the effects of 6 weeks of treatment with prescription omega-3-acid ethyl esters (POM3, 4 g/day) versus placebo (soy oil) on low-density lipoprotein cholesterol (LDL-C) and other aspects of the fasting lipid profile in 31 men and women with primary, isolated hypercholesterolemia (LDL-C 130-220 mg/dL and triglycerides less than 150 mg/dL while free of lipid-altering therapies). Mean ± standard error of the mean baseline concentrations of total cholesterol, LDL-C, high-density lipoprotein cholesterol (HDL-C), very-low-density lipoprotein cholesterol, and triglycerides were 229 ± 3, 146 ± 3, 60 ± 2, 23 ± 2, and 113 ± 8 mg/dL, respectively. POM3 produced a modest increase from baseline in LDL-C (3.4%) versus the placebo response (-0.7%, P = 0.010). Significant changes (P < 0.05) for POM3 (placebo-corrected) were observed for very-low-density lipoprotein cholesterol (-18.8%), triglycerides (-18.7%), and HDL-C (3.3%). Nuclear magnetic resonance-determined very-low-density lipoprotein particle concentration and size and HDL particle concentration decreased significantly more with POM3 versus placebo, whereas LDL and HDL particle sizes increased significantly more with POM3 versus placebo. Total cholesterol, non-HDL-C, apolipoproteins A1 and B, and LDL particle concentration responses did not differ between treatments. These results did not confirm the hypothesis that POM3 treatment would lower LDL-C in primary, isolated hypercholesterolemia. Effects on other variables were consistent with prior results in mixed dyslipidemia.
Trial registration: ClinicalTrials.gov NCT00678743.