Steady-state bioavailability of prescription omega-3 on a low-fat diet is significantly improved with a free fatty acid formulation compared with an ethyl ester formulation: the ECLIPSE II study

Vasc Health Risk Manag. 2013;9:563-73. doi: 10.2147/VHRM.S50464. Epub 2013 Oct 1.


The systemic bioavailability of free fatty acid (FFA) forms of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) compared with ethyl ester (EE) forms is dependent on the presence of intestinal lipases and is highest during consumption of high-fat meals. Given that patients with cardiovascular disease are advised to reduce dietary fat intake, potentially lowering the bioavailability and therapeutic benefit, the hypothesis that FFA forms provide for higher bioavailability compared with EE forms under low-fat diet conditions was tested where the pharmacokinetics of the FFA form (Epanova™) were compared with those of an ethyl ester form (Lovaza®) following repeat dosing. Fifty-two healthy male and female subjects were equally allocated to one of two open-label, parallel-group cohorts. Following a Therapeutic Lifestyle Changes diet for a minimum of 7 days, blood samples were drawn for endogenous values for EPA and DHA over a 24-hour period. Subjects were then administered 4 × 1 g capsules of either Epanova (OM3 FFA) or Lovaza (OM3 EE) once daily for 14 days, following which serial blood samples were drawn over a 24-hour period to characterize the bioavailability of EPA and DHA from the respective formulations. In addition, changes from baseline in lipid profile were explored. Systemic bioavailability, as measured by area under the curve from time zero to 24 hours (AUC(0-τ)) and the maximum measured plasma concentrations during the 0-24 hour dosing interval (C(max,ss)) of unadjusted total plasma EPA + DHA were approximately 3-fold and 3.9-fold higher, respectively, for Epanova relative to Lovaza. Following baseline adjustment, the magnitude of difference in bioavailability was approximately 5.8-fold and 6.5-fold higher in AUC(0-τ) and C(max,ss), respectively, for Epanova relative to Lovaza. Serum triglycerides were reduced by a significantly greater extent (P = 0.013) for Epanova relative to Lovaza (21% versus 8%). The bioavailability of the FFA forms of EPA and DHA in Epanova are significantly greater than the bioavailability from the EE forms present in Lovaza under low-fat dietary conditions normally recommended for patients with cardiovascular disease. This increased bioavailability may lead to improved triglyceride-lowering in patients with hypertriglyceridemia.

Keywords: docosahexaenoic acid; eicosapentaenoic acid; hypertriglyceridemia; pharmacokinetics.

Publication types

  • Clinical Trial
  • Comparative Study

MeSH terms

  • Administration, Oral
  • Area Under Curve
  • Biological Availability
  • Chemistry, Pharmaceutical
  • Cholesterol / blood
  • Diet, Fat-Restricted*
  • Dietary Supplements*
  • Docosahexaenoic Acids / administration & dosage
  • Docosahexaenoic Acids / adverse effects
  • Docosahexaenoic Acids / blood
  • Docosahexaenoic Acids / chemistry
  • Docosahexaenoic Acids / pharmacokinetics*
  • Drug Combinations
  • Eicosapentaenoic Acid / administration & dosage
  • Eicosapentaenoic Acid / adverse effects
  • Eicosapentaenoic Acid / blood
  • Eicosapentaenoic Acid / chemistry
  • Eicosapentaenoic Acid / pharmacokinetics*
  • Esters / administration & dosage
  • Esters / adverse effects
  • Esters / blood
  • Esters / chemistry
  • Esters / pharmacokinetics*
  • Fatty Acids, Nonesterified / administration & dosage
  • Fatty Acids, Nonesterified / adverse effects
  • Fatty Acids, Nonesterified / blood
  • Fatty Acids, Nonesterified / chemistry
  • Fatty Acids, Nonesterified / pharmacokinetics*
  • Fatty Acids, Omega-3 / administration & dosage
  • Fatty Acids, Omega-3 / adverse effects
  • Fatty Acids, Omega-3 / blood
  • Fatty Acids, Omega-3 / chemistry
  • Fatty Acids, Omega-3 / pharmacokinetics*
  • Female
  • Humans
  • Least-Squares Analysis
  • Male
  • Models, Biological
  • Triglycerides / blood


  • Drug Combinations
  • Esters
  • Fatty Acids, Nonesterified
  • Fatty Acids, Omega-3
  • Triglycerides
  • Docosahexaenoic Acids
  • Cholesterol
  • Eicosapentaenoic Acid
  • Omacor