Products containing omega-3 fatty acids, such as krill oil and fish oils, have been effective in lowering triglyceride levels. Although no data have suggested that the low-density lipoprotein-cholesterol (LDL-C) increases associated with some omega-3 fatty acid formulations lead to adverse outcomes, these elevations in LDL-C levels may compromise the achievement of lipid targets. Thus, there is a need for agents that can lower triglyceride levels without increasing LDL-C levels.
The triglyceride (TG)-lowering benefits of the very-long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are well documented. Available as prescription formulations and dietary supplements, EPA and DHA are recommended by the American Heart Association for patients with coronary heart disease and hypertriglyceridemia. Dietary supplements are not subject to the same government regulatory standards for safety, efficacy, and purity as prescription drugs are; moreover, supplements may contain variable concentrations of EPA and DHA and possibly other contaminants. Reducing low-density lipoprotein-cholesterol (LDL-C) levels remains the primary treatment goal in the management of dyslipidemia. Dietary supplements and prescription formulations that contain both EPA and DHA may lower TG levels, but they may also increase LDL-C levels.
Two prescription formulations of long-chain omega-3 fatty acids are available in the U.S. Although prescription omega-3 acid ethyl esters (OM-3-A EEs, Lovaza) contain high-purity EPA and DHA, prescription icosapent ethyl (IPE, Vascepa) is a high-purity EPA agent. In clinical trials of statin-treated and non–statin-treated patients with hypertriglyceridemia, both OM-3-A EE and IPE lowered TG levels and other atherogenic markers; however, IPE did not increase LDL-C levels.
Results of recent outcomes trials of long-chain omega-3 fatty acids, fibrates, and niacin have been disappointing, failing to show additional reductions in adverse cardiovascular events when combined with statins. Therefore, the REDUCE–IT study is being conducted to evaluate the effect of the combination of IPE and statins on cardiovascular outcomes in high-risk patients. The results of this trial are eagerly anticipated.