What the Pelacarsen Trial Result Means

Novartis has announced on September 4, 2026 that pelacarsen did not meet its primary endpoint in the Phase III Lp(a)HORIZON trial. The study was designed as a randomized, double-blind, placebo-controlled cardiovascular outcomes trial and was intended to test whether lowering Lp(a) reduces major heart events. The question has been central in cardiology because Lp(a) is largely genetic and affects about one in five people worldwide.

The trial enrolled 8,323 patients with elevated Lp(a) who were receiving guideline-directed therapies. Pelacarsen substantially lowered Lp(a) levels, but this has not translated into fewer cardiovascular deaths, heart attacks, strokes, or urgent revascularizations in the overall study population. Full Lp(a)HORIZON data will be presented at an upcoming medical congress. Experts have said the topline result will inform future research on Lp(a) and on how genetic risk factors are targeted in practice.

Ionis has noted that pelacarsen demonstrated an acceptable safety profile in the trial. The companies have emphasized that the results will be shared at a scientific meeting and that detailed analyses are under way.