What Novartis announced. In a September 4 release, Novartis said the Lp(a)HORIZON phase III trial did not meet its primary endpoint: a composite of cardiovascular death, non-fatal heart attack, non-fatal stroke and urgent coronary revascularization requiring hospital admission. The trial enrolled 8,323 patients with elevated Lp(a) and established atherosclerotic cardiovascular disease. Lp(a) was lower on pelacarsen. BioPharma Dive put the reduction at about 80%. These are company topline results. The full data go to a medical congress later.
Why the drug mattered to testing. The guideline describes Lp(a) levels as genetically driven. BioPharma Dive reports that physicians often skip the test because no drug exists to act on a result. A positive trial would have changed that. A negative one leaves the situation where it was in 2025.
What the trial cannot tell you. Every participant already had cardiovascular disease, and TCTMD reports mean LDL cholesterol around 66 mg/dL on standard treatment, so the background risk was well managed. It tested one drug, one mechanism, one population. Analysts quoted by BioPharma Dive still want to know how baseline Lp(a) related to benefit, how much lowering is enough, and how close the result came to significance. Amgen’s olpasiran and Lilly’s lepodisiran are still in development. BioPharma Dive notes olpasiran’s deeper lowering (over 95%) could matter if depth drives benefit. I found no outcomes report from either.
What the guideline says. The 2026 ACC/AHA dyslipidemia guideline, published in May, gives a Class 1 recommendation to measure Lp(a) once in an adult’s lifetime. TCTMD summarizes it: an elevated level is an indication for more intensive LDL-cholesterol lowering and management of other risk factors, also Class 1. Neither recommendation names an Lp(a)-lowering drug, so the trial result removes nothing the guideline said. Whether its authors change anything will depend on the full data.
Reading your number. Healio’s guideline summary treats 125 nmol/L or higher as a risk enhancer, with roughly 1.4 times the cardiovascular risk, and 250 nmol/L or higher as more than double. TCTMD quotes the same threshold as 50 mg/dL. Do not convert between the two yourself. A 2023 survey of UK laboratories states that converting mass units to molar units introduces inaccuracy, and recommends nmol/L for reporting. Compare your result with the threshold in the unit printed on your report.
If your Lp(a) is high. The guideline’s answer is unchanged: push down what you can. That means LDL cholesterol (or ApoB, if you have it), blood pressure, glucose, and smoking, in a conversation with a clinician who has seen the number. If you have never had it measured, it usually has to be requested by name. Our lipid panel guide covers what a standard panel leaves out.
What to watch. Two things would change the picture: the full Lp(a)HORIZON dataset, and outcomes from the trials of olpasiran and lepodisiran. If deeper lowering turns out to matter, the drug case reopens. If it does not, Lp(a) stays a risk marker you test once and manage around.
Lp(a) is one of the lipid markers a routine panel skips. See how to read a lipid panel and what a high LDL result means, the marker the guideline tells you to tighten when Lp(a) is high.