Cholesterol Drug Fails to Prevent Heart Attacks in Trial

Novartis' experimental drug pelacarsen failed to prevent heart attacks or strokes in a major clinical trial. The drug, which targets lipoprotein(a) or Lp(a), did not show any measurable impact on cardiovascular outcomes.

The Horizon trial, presented at the American Heart Association meeting, involved 8,322 patients with high Lp(a) levels and a history of heart attack, stroke, or other heart problems within 10 years of starting the trial.

While pelacarsen reduced Lp(a) by 78%, compared to a 13% reduction with a placebo, these levels did not translate to improved cardiovascular health. The findings were published in the New England Journal of Medicine.

Dr. Steven Nissen, who led the trial, expressed surprise at the results. He had expected significant benefits from lowering Lp(a), but the data showed no such outcomes. Other experts, including Dr. Karol Watson, called the results shocking and unexpected.

Researchers are exploring possible reasons for the drug's lack of effect. One theory is that the therapy was administered too late in life, as the average age of participants was 60, and they were followed for five years. Lp(a) is genetic, so early intervention may be key.

Despite the trial's failure, experts emphasize that Lp(a) remains a valuable marker for heart disease risk. Guidelines now recommend measuring Lp(a) for all adults, and further research into other drugs targeting Lp(a) is ongoing.