Amarin Corporation (NASDAQ: AMRN) announced results from a post hoc analysis of the REDUCE-IT trial presented at the European Atherosclerosis Society Congress 2026. The analysis examined risk-weighted apolipoprotein B as a potential biomarker for identifying cardiovascular risk in statin-treated patients with elevated triglycerides.

The study evaluated 3,485 participants from the REDUCE-IT placebo arm over a median follow-up of 4.9 years. Risk-weighted apoB levels were calculated to be approximately 30% higher than measured apoB. The analysis found that risk-weighted apoB demonstrated superior risk prediction for cardiovascular outcomes compared with LDL-C, non-HDL-C, and apoB in this patient population.

Risk-weighted apoB incorporates differential weights for lipid components, including triglyceride-rich lipoproteins and lipoprotein(a), which research indicates are 4-5 and 6-7 times more atherogenic per particle than LDL, respectively.

"By incorporating the relative atherogenicity of triglyceride-rich lipoproteins and lipoprotein(a), risk-weighted apoB provides a more integrated assessment of lipid-related risk," said Michaela B. Rehman, lead author of the analysis from Ramsay Santé, Médipôle Lyon-Villeurbanne.

The application of European Society of Cardiology intervention thresholds identified more patients at elevated risk using risk-weighted apoB compared with apoB alone. The REDUCE-IT trial previously demonstrated that icosapent ethyl treatment reduced major adverse cardiovascular events in high-risk, statin-treated patients with elevated triglycerides.

Amarin's icosapent ethyl product is marketed as VASCEPA in the United States and VAZKEPA in Europe, approved for cardiovascular risk reduction in specific patient populations based on the REDUCE-IT evidence.