pelacarsen - (Lp(a)HORIZON)

September 4, 2026: Ionis Pharmaceuticals (NASDAQ: IONS) said partner Novartis reported that the Phase 3 Lp(a)HORIZON trial of pelacarsen did not meet its primary endpoint of reducing 4-point major adverse cardiovascular events versus placebo in patients with elevated lipoprotein(a) and established cardiovascular disease. The composite endpoint included cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, and urgent coronary revascularization requiring hospitalization.

The study enrolled 8,323 patients and evaluated outcomes in the overall population with Lp(a) ≥70 mg/dL and a subpopulation with Lp(a) ≥90 mg/dL. Pelacarsen substantially lowered Lp(a) levels, consistent with prior studies, but this did not translate into cardiovascular risk reduction. The drug showed an acceptable safety profile.

Full Lp(a)HORIZON data will be presented at an upcoming medical congress.

Pelacarsen is an investigational antisense oligonucleotide designed to inhibit Lp(a) production. Ionis discovered pelacarsen and conducted early development; Novartis licensed development and commercialization rights in February 2019.