Pelacarsen failed to reduce cardiovascular events in the clinical trial
Novartis’s experimental drug pelacarsen lowered lipoprotein(a) by 78% but did not reduce major cardiovascular events in the Horizon trial, Cleveland Clinic reported. After 4.7 years, the trial’s primary endpoint—heart-related death, heart attack, stroke or urgent heart procedure—occurred in 12.3% of patients taking pelacarsen and 12.1% receiving placebo. NBC News said 8,322 people participated.
More context
A large clinical trial found that pelacarsen, an experimental Novartis drug, lowered lipoprotein(a) but did not reduce major cardiovascular events in people with high levels of the inherited risk factor. The Horizon trial results were presented Saturday at an American Heart Association meeting, NBC News reported. It enrolled 8,322 people with existing cardiovascular disease and elevated Lp(a). After 4.7 years of follow-up, the primary endpoint—heart-related death, heart attack, stroke or an urgent heart procedure requiring hospitalization—occurred in 12.3% of participants receiving pelacarsen and 12.1% receiving placebo, according to Cleveland Clinic, which led the trial. Pelacarsen lowered Lp(a) by 78%, compared with 13% with placebo. The trial also reported mild side effects and rare allergic reactions. NBC News said researchers were stunned, calling the result a massive blow to preventive cardiology.
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Reporting
- NBC News — Cholesterol drug pelacarsen fails to prevent heart attacks in major trial
- clevelandclinic.org — Cleveland Clinic Trial Shows Novel Lipoprotein(a) Drug Did Not Reduce Major Cardiovascular Events After Nearly 5 Years
- wkyc.com — 7-year heart trial finds Lp(a) drug doesn’t prevent heart attacks, but testing still matters
- google.com — Pelacarsen, a promising drug for an inherited heart risk, flops, stunning doctors
Verifier’s note
NBC News, Cleveland Clinic, WKYC and CNN report that pelacarsen lowered Lp(a) but did not reduce major cardiovascular events, including heart attacks and strokes. This matches the proposed event and was reported on November 7, 2026.