Highlights
Among patients with established atherosclerosis or high-risk diabetes but no prior myocardial infarction or stroke, higher baseline lipoprotein(a), or Lp(a), was independently associated with a higher risk of major coronary events.
The excess risk appeared to be driven mainly by myocardial infarction rather than ischemic stroke. In the placebo arm, every 100 nmol/L increase in baseline Lp(a) was associated with a 15% higher adjusted risk of major coronary events and a 23% higher adjusted risk of myocardial infarction.
Evolocumab lowered LDL-C substantially across the study population and produced larger absolute reductions in Lp(a) among those with higher baseline Lp(a). Relative risk reduction in major coronary events was similar regardless of baseline Lp(a), but absolute benefit was numerically greater in patients with elevated Lp(a), yielding a lower number needed to treat over 5 years.
These findings support Lp(a) as a clinically useful marker of residual coronary risk in primary prevention patients with advanced atherosclerotic risk, even when it does not clearly identify a subgroup with differential relative responsiveness to PCSK9 inhibition.
Background and Clinical Context
Lipoprotein(a) has re-emerged as a major focus in preventive cardiology. Structurally, Lp(a) is an LDL-like particle linked to apolipoprotein(a), a moiety with proatherogenic, proinflammatory, and potentially prothrombotic properties. Unlike standard lipids, Lp(a) is largely genetically determined and is not meaningfully modified by lifestyle measures. This makes it particularly relevant in patients who continue to face substantial atherosclerotic cardiovascular disease risk despite otherwise appropriate risk factor management.
Observational, genetic, and Mendelian randomization data have consistently supported Lp(a) as a causal risk factor for coronary heart disease and aortic valve stenosis. Its role in ischemic stroke has been less consistent and may vary by population, stroke subtype, and competing vascular mechanisms. Current preventive cardiology practice increasingly incorporates one-time Lp(a) testing, especially in those with premature cardiovascular disease, strong family history, recurrent events despite lipid lowering, or unexplained residual risk.
PCSK9 inhibitors lower LDL-C robustly and also reduce Lp(a) modestly. Prior secondary prevention analyses, including from the FOURIER program, suggested that patients with elevated Lp(a) may derive greater absolute benefit from PCSK9 inhibition because they begin at higher baseline risk. What remained uncertain was whether this pattern would also apply to a population without prior myocardial infarction or stroke but still at high risk because of established atherosclerosis or diabetes. The VESALIUS-CV trial addresses this important gap.
Study Design
Trial overview
VESALIUS-CV was a randomized, placebo-controlled cardiovascular outcomes trial that enrolled patients from June 2019 through November 2021. Participants had qualifying atherosclerosis or high-risk diabetes but no prior myocardial infarction or stroke. The median follow-up was 4.6 years.
Population for the present analysis
This was a prespecified analysis of 7,557 patients in whom Lp(a) was measured at baseline. The cohort had a median age of 66 years, with an interquartile range of 60 to 71 years, and 42.8% were women. Median baseline Lp(a) was 28 nmol/L, with a broad interquartile range of 9 to 132 nmol/L, underscoring the marked heterogeneity of inherited Lp(a) burden in clinical practice.
Intervention and comparator
Patients were randomized to evolocumab or placebo on top of background preventive therapy. As expected for a PCSK9 inhibitor, evolocumab produced major LDL-C lowering and a more modest but clinically relevant reduction in Lp(a).
Outcomes and statistical approach
The primary outcome examined in this analysis was the composite of major coronary events, defined as coronary heart disease death, myocardial infarction, or urgent coronary revascularization. Investigators used Cox proportional hazards models to evaluate two questions: first, whether baseline Lp(a) predicted cardiovascular events in the placebo arm after adjustment for relevant covariates; and second, whether baseline Lp(a) modified the efficacy of evolocumab.
This analytical framing is important. By focusing on the placebo arm for prognostic modeling, the authors sought to isolate the natural relationship between Lp(a) and outcomes. By then examining treatment effect across baseline Lp(a), they tested whether Lp(a) is not only a risk marker but also a treatment-selection marker.
Key Results
Baseline Lp(a) predicted major coronary events
In patients assigned to placebo, higher baseline Lp(a) was independently associated with greater risk of major coronary events. The adjusted hazard ratio per 100 nmol/L increase in Lp(a) was 1.15, with a 95% confidence interval of 1.05 to 1.26 and a P value of 0.004. This indicates that the association was statistically robust even after multivariable adjustment.
Clinically, the magnitude is meaningful. Because Lp(a) values can vary widely, often by several hundred nmol/L between individuals, the cumulative increase in risk across the distribution may be substantial. The finding supports the idea that Lp(a) captures residual coronary risk not fully represented by standard lipid measures.
The signal was strongest for myocardial infarction
The association between Lp(a) and myocardial infarction was even stronger. The adjusted hazard ratio per 100 nmol/L increase was 1.23, with a 95% confidence interval of 1.10 to 1.38 and P less than 0.001. This suggests that Lp(a) may be particularly linked to plaque-related coronary instability or thrombosis leading to infarction.
By contrast, baseline Lp(a) was not associated with ischemic stroke in this analysis. The hazard ratio per 100 nmol/L increase was 1.00, with a 95% confidence interval of 0.84 to 1.19 and P equal to 0.99. This null finding is notable because it reinforces the possibility that Lp(a)-related risk is more tightly connected to coronary than cerebrovascular events in this specific high-risk population without prior stroke.
Evolocumab lowered LDL-C and reduced Lp(a), especially when baseline Lp(a) was high
After 48 weeks, evolocumab reduced LDL-C by 66.8 mg/dL in patients with baseline Lp(a) above 105 nmol/L, compared with 61.1 mg/dL in those with baseline Lp(a) at or below 105 nmol/L. This confirms consistent and profound LDL-C lowering across strata.
The effect on Lp(a) showed greater absolute separation by baseline Lp(a). In patients with Lp(a) above 105 nmol/L, evolocumab reduced Lp(a) by 38.0 nmol/L, whereas in those with Lp(a) 105 nmol/L or lower, the reduction was 6.0 nmol/L. This pattern is expected because higher baseline concentrations permit larger absolute decrements even when proportional reduction is modest.
Relative treatment benefit was similar across Lp(a) levels
The key therapeutic question was whether elevated Lp(a) identified patients who experienced a larger relative effect of evolocumab on major coronary events. The answer was no, at least statistically. In patients with baseline Lp(a) above 105 nmol/L, evolocumab reduced the risk of major coronary events by 41%, corresponding to a hazard ratio of 0.59 and a 95% confidence interval of 0.41 to 0.83. In those with lower baseline Lp(a), the relative reduction was 35%, with a hazard ratio of 0.65 and a 95% confidence interval of 0.51 to 0.82.
These point estimates are directionally similar, and the interaction P value was 0.45 when Lp(a) was modeled as a continuous variable. In practical terms, this means baseline Lp(a) did not significantly modify the relative efficacy of evolocumab. Elevated Lp(a) marks higher risk, but it did not identify a subgroup with conclusively greater proportional response to treatment.
Absolute benefit was numerically greater when Lp(a) was elevated
Although relative risk reduction was similar, absolute risk reduction was larger in those with higher baseline Lp(a). The absolute reduction in major coronary events was 3.7% in patients with Lp(a) above 105 nmol/L compared with 2.5% in those with lower Lp(a). The interaction P value for absolute risk reduction was 0.09, which does not meet a conventional threshold for statistical significance but suggests a clinically relevant trend.
The corresponding number needed to treat at 5 years was 28 in the elevated Lp(a) group versus 40 in the lower Lp(a) group. From a clinical and policy perspective, this may be one of the most actionable findings in the report. Even without differential relative efficacy, risk enrichment through Lp(a) testing can identify patients more likely to realize larger absolute event reduction from intensive lipid-lowering therapy.
Clinical Interpretation
Lp(a) appears to be a risk-enrichment biomarker rather than a response-prediction biomarker
The distinction matters. A predictive biomarker identifies who will respond more strongly, proportionally, to a treatment. A prognostic biomarker identifies who is at higher baseline risk. In VESALIUS-CV, Lp(a) behaved primarily as a prognostic marker. Patients with higher Lp(a) had more coronary events, and therefore the same or similar relative benefit translated into greater absolute gain.
This is highly relevant to contemporary prevention practice. Clinicians often ask whether measuring Lp(a) will change management. These data suggest that in selected high-risk patients without prior myocardial infarction or stroke, the answer may be yes, not because evolocumab works differently, but because Lp(a) helps define a higher-risk phenotype in which treatment yield is greater.
Why no clear association with ischemic stroke?
The absence of a stroke association should be interpreted carefully. It does not necessarily mean Lp(a) is irrelevant to cerebrovascular disease. Stroke is biologically heterogeneous, with large-artery atherosclerotic, cardioembolic, lacunar, and cryptogenic mechanisms grouped together in many trials. If Lp(a) exerts its strongest effect through coronary plaque biology or through specific arterial beds, signal dilution may occur in broader stroke composites. Event numbers and statistical power also matter. Nonetheless, the present findings are a reminder that coronary and cerebrovascular risk markers do not always behave identically.
What do these data add beyond prior PCSK9 inhibitor experience?
Earlier work, especially in secondary prevention populations, showed that elevated Lp(a) is associated with residual risk and that PCSK9 inhibitors lower both LDL-C and Lp(a). VESALIUS-CV extends those observations into a population without prior myocardial infarction or stroke, a group often considered closer to primary prevention but still carrying substantial vascular risk. This is important because prevention strategies are increasingly moving earlier in the disease course, before irreversible clinical events occur.
Strengths and Limitations
Strengths
This analysis has several strengths. It was prespecified, derived from a large randomized outcomes trial, and used adjudicated clinical events with long follow-up. The population addresses an under-studied but clinically important group: patients with atherosclerosis or high-risk diabetes who have not yet sustained myocardial infarction or stroke. The analysis also distinguishes relative from absolute treatment effects, a crucial point for real-world therapeutic decision-making.
Limitations
Several limitations deserve attention. First, the analysis included only patients with available baseline Lp(a) measurements, which may introduce selection considerations, although this is common in biomarker substudies. Second, interaction analyses are typically underpowered relative to main-effect analyses; therefore, failure to detect heterogeneity in relative treatment effect should not be overinterpreted as proof of complete uniformity across all Lp(a) concentrations. Third, the trial was not designed to test whether Lp(a) lowering itself mediates event reduction, since evolocumab also markedly lowers LDL-C. The observed benefit cannot be partitioned cleanly into LDL-C-dependent and Lp(a)-dependent components.
Another limitation is external generalizability. The enrolled population was high risk by design, so these findings should not be automatically extrapolated to lower-risk primary prevention populations. In addition, Lp(a) assays and reporting units vary across practices, and implementation remains uneven. Finally, the abstract does not provide detailed safety results for this specific subgroup analysis, so safety interpretation should rely on the parent trial report.
Implications for Practice and Research
For practicing clinicians, the take-home message is straightforward. Measuring Lp(a) can help identify patients with atherosclerosis or high-risk diabetes who remain at elevated coronary risk even without prior myocardial infarction or stroke. In such patients, intensifying lipid-lowering therapy with evolocumab may yield clinically meaningful absolute benefit, particularly when Lp(a) is elevated.
For guideline developers and payers, the study supports Lp(a) as a risk-stratification tool in preventive cardiology rather than a strict companion diagnostic for PCSK9 inhibitor use. This distinction may matter in access frameworks, where absolute risk reduction and number needed to treat often drive value assessments more than biomarker-defined relative efficacy.
For researchers, the trial reinforces the need for dedicated Lp(a)-lowering therapies. Because evolocumab lowers Lp(a) only modestly relative to emerging antisense and small interfering RNA agents, VESALIUS-CV cannot answer whether specifically targeting Lp(a) will further reduce coronary events in this population. Ongoing and future outcome trials of selective Lp(a)-lowering strategies will be critical.
Conclusion
The VESALIUS-CV prespecified analysis shows that in patients with atherosclerosis or high-risk diabetes but no prior myocardial infarction or stroke, elevated baseline Lp(a) independently identifies a higher risk of major coronary events, especially myocardial infarction. Evolocumab reduced major coronary events across Lp(a) levels with no statistically significant evidence of differential relative efficacy. However, because patients with elevated Lp(a) started at higher risk, their absolute benefit was numerically greater, translating into a more favorable number needed to treat. In current practice, these findings strengthen the case for Lp(a) measurement as a tool for residual risk assessment and therapeutic prioritization in high-risk cardiovascular prevention.
Funding and ClinicalTrials.gov
The abstract cited does not detail funding within the summary text, but VESALIUS-CV is an evolocumab outcomes trial associated with Amgen. The trial is registered at ClinicalTrials.gov as NCT03872401.
Citation
Monguillon V, Marston NA, Bohula EA, Park JG, Kuder JF, Murphy SA, De Ferrari GM, Leiter LA, Nicolau JC, Ebenbichler C, Sinnaeve P, Goudev A, Budaj A, Averkov O, Tokgozoglu L, Blankstein R, Vinereanu D, Giugliano RP, Sabatine MS, O’Donoghue ML. Lipoprotein(a) Levels, Risk of Cardiovascular Events and Benefit of Evolocumab: Findings From the VESALIUS-CV Trial. Circulation. 2026-05-25. PMID: 42183757. https://pubmed.ncbi.nlm.nih.gov/42183757/
Selected References
O’Donoghue ML, Giugliano RP, Keech AC, et al. Lipoprotein(a), PCSK9 inhibition, and cardiovascular risk. Circulation. 2019;139(12):1483-1492.
Tsimikas S, Karwatowska-Prokopczuk E, Gouni-Berthold I, et al. Lipoprotein(a) reduction in persons with cardiovascular disease. N Engl J Med. 2020;382(3):244-255.
Mach F, Baigent C, Catapano AL, et al. 2019 ESC/EAS Guidelines for the management of dyslipidaemias. Eur Heart J. 2020;41(1):111-188.
Wilson DP, Jacobson TA, Jones PH, et al. Use of lipoprotein(a) in clinical practice: a biomarker whose time has come. A scientific statement from the National Lipid Association. J Clin Lipidol. 2022;16(1):e77-e95.