Reacción a "Results are presented from the unsuccessful first clinical trial that aimed to reduce cardiovascular risk by lowering lipoprotein(a) levels"

Lipoprotein(a), or Lp(a), is a particle that circulates in the blood—similar to LDL cholesterol—with levels determined primarily by genetics. For years, it has been known that individuals with high concentrations face an increased risk of cardiovascular disease, such as myocardial infarction (heart attack) or stroke, even when their cholesterol levels are well-controlled. Consequently, there were high expectations surrounding new treatments capable of lowering it.

The Lp(a)HORIZON study is a high-quality clinical trial involving more than 8,300 patients, with a follow-up period of nearly five years. Its results, however, are somewhat disappointing. Although pelacarsen succeeded in reducing Lp(a) levels by approximately 73%, this reduction did not translate into a decrease in cardiovascular events. The cardiovascular complications studied occurred with virtually the same frequency in treated patients as in those who received a placebo. This finding is significant because it serves as a reminder that lowering a risk marker in a blood test does not necessarily equate to reducing the risk of developing a disease. It encourages us to consider a comprehensive approach that addresses all vascular risk factors.

Nevertheless—and this is an important point—the study does not call into question the evidence linking Lp(a) to cardiovascular risk, nor does it suggest that we should stop measuring it. Knowing a patient’s Lp(a) levels remains useful for identifying those at higher risk and for strengthening the management of other factors, particularly LDL cholesterol.

One limitation is that the trial was conducted on patients who already had cardiovascular disease; therefore, the results cannot be directly extrapolated to healthy individuals with elevated Lp(a). Furthermore, it is possible that other treatments, mechanisms, or earlier intervention strategies could yield different outcomes.

Ultimately, while this represents a significant setback for the expectations placed on pelacarsen, it does not necessarily mark the end of strategies targeting Lp(a). What is clear is that any new treatment must demonstrate that, in addition to reducing these levels, it truly improves the patients' prognosis.