Amarin Corporation plc highlighted two data presentations at ACC.24 describing the effects of VASCEPA®/VAZKEPA® (icosapent ethyl) on reducing MACE (Major Adverse Cardiovascular Events) in patients with baseline high or low Lipoprotein(a) [Lp(a)] levels, as well as reducing the risk of cardiovascular (CV) events in patients irrespective of baseline LDL-C level. The REDUCE-IT analysis results relating Lp(a) concentrations with CV risk were also published online in the Journal of the American College of Cardiology (JACC). High Lp(a) concentrations are associated with increased CV event risk, even when LDL-C levels are well-managed.

There are no treatments currently approved to reduce residual CV risk on top of contemporary medical therapy in patients with high Lp(a) levels. In this post hoc analysis of REDUCE-IT, the relationship between continuous baseline Lp(a) concentration and risk of MACE was analyzed in models that also accounted for baseline LDL-C, baseline triglycerides (TG), and double-blind treatment. REDUCE-IT participants were randomized to receive either 2g twice daily of icosapent ethyl (IPE) or matching placebo and followed for a median 4.9 years.

In this subanalysis, there were 7,026 REDUCE-IT patients with baseline Lp(a) data and a median Lp(a) value of 11.6 (Q1-Q3: 5.0-37.4) mg/dL. Results showed that baseline Lp(a) had a strong and significant relationship with MACE irrespective of baseline LDL-C, baseline TGs, and treatment assignment, and that the benefit of IPE was consistent across Lp(a) concentrations. Importantly, the treatment benefit of IPE was evident across subgroups with both high (=50 mg/dL) and low (<50 mg/dL) Lp(a) concentrations.

Specifically, for first MACE, the relative IPE treatment effects for Lp(a) =50 mg/dL and <50 mg/dL were HR 0.79 (95% CI 0.64-0.97; P=0.0248) and HR 0.75 (95% CI 0.66-0.84; P<0.0001), respectively. Absolute risk reductions at 5 years with IPE were 6.5% and 5.7% for Lp(a) =50 mg/dL and <50 mg/dL, respectively. Limitations include that participants in REDUCE-IT were not selected on the basis of their baseline Lp(a) concentration and that not all REDUCE-IT patients had available baseline Lp(a) data.

Elevated low-density lipoprotein cholesterol (LDL-C) is a well-established major CV risk factor supported by clinical evidence showing decreased atherosclerotic disease events when LDL-C is therapeutically lowered. Recent international guidelines recommend lowering LDL-C to <55 mg/dL in those patients who are at very high risk for a future CV event. In this post hoc analysis, investigators explored REDUCE-IT data to determine if IPE reduces CV outcomes among high-risk CV patients irrespective of baseline LDL-C. Patients were stratified by LDL-C <55 vs =55 mg/dL.

The primary outcome was a composite of CV death, nonfatal myocardial infarction, nonfatal stroke, coronary revascularization, or unstable angina. Among statin-treated REDUCE-IT patients with baseline LDL-C data, 1,058 (12.9%) had LDL-C <55 mg/dL and 7,117 (87.1 %) had LDL-C =55 mg/dL. The primary outcome rate among patients with LDL-C <55 mg/dL was 16.2% in the IPE group and 22.8% in the placebo group, HR 0.66 (95% CI 0.50-0.87; P=0.003).

Findings were consistent in the LDL-C =55 mg/dL subgroup, with rates of 17.4% in the IPE group and 21.9% in the placebo group, HR 0.76 (95% CI 0.69-0.85; P<0.0001). No significant interaction by baseline LDL-C was observed.