Novartis and Ionis heart drug fails Phase III clinical trial

Novartis and Ionis Pharmaceuticals announced that the experimental drug pelacarsen failed to meet its primary endpoint in a Phase III clinical trial. The study, known as Lp(a)Horizon, involved 8,323 patients with elevated lipoprotein(a) levels and cardiovascular disease.

While the drug successfully lowered levels of lipoprotein(a)—a type of lipid linked to higher cardiovascular risk—it did not significantly reduce the risk of major cardiovascular events, such as heart attack, stroke, or death, compared to a placebo.

The failure has significant implications for both companies. For Ionis, shares fell 12% in aftermarket trading following the news. For Novartis, the setback impacts a pipeline that includes several experimental drugs representing over $10 billion in potential peak annual sales. Currently, there are no approved treatments specifically designed to lower lipoprotein(a), though competitors such as Amgen and Eli Lilly are developing similar therapies in late-stage development.