1 in 5 adults carry an inherited heart risk. New drugs are racing to treat it.

A patient on a statin, eating the Mediterranean diet her cardiologist recommended, and walking most days can still carry a cardiovascular risk that diet, exercise, and her existing medication cannot reach: lipoprotein(a), a cholesterol-like particle about 1 in 5 adults inherit from a single parent. Standard lipid panels do not measure it. Existing therapies, including statins and PCSK9 inhibitors, do not move it meaningfully. Elevated lipoprotein(a) is, in practice, a genetic condition the current standard of care cannot treat.

Three Big Pharma companies are now running cardiovascular outcomes trials to find out whether lowering the particle actually prevents heart attacks. Novartis's pelacarsen, an antisense oligonucleotide designed to block the gene that produces apolipoprotein(a), is the front-runner in the Lp(a)HORIZON phase 3 study, which has been enrolling high-risk patients since 2020. Amgen's olpasiran, a small interfering RNA therapy that silences the same gene, is enrolling in OCEAN(a)-Outcomes, building on phase 2 data presented at the European Society of Cardiology congress in 2023 (Amgen press release; follow-on). Eli Lilly has two late-stage assets running in parallel: lepodisiran, which Pharmacy Times reported reduced lipoprotein(a) by nearly 94% in adults with elevated baseline levels, and muvalaplin, the first oral small molecule in the field, which significantly lowered the same marker in adults at high cardiovascular risk. The four-program race, the first test of multiple mechanism-specific therapies at the same question in the same window, is the framing STAT+ has now put on the field.

The bet is large because the field has a mixed record. Lipoprotein(a) has been a known cardiovascular risk factor for decades, and earlier programs to lower it did not always translate the surrogate into fewer heart attacks. The current wave leans on three newer mechanism classes, antisense oligonucleotides, siRNA, and an oral small molecule, but the legitimate critical frame is that the readout, not the mechanism, is the actual news. A drug that drops lipoprotein(a) by 90% but leaves the heart attack rate flat would still be a successful biomarker intervention and a failed commercial one.

Regulators have not committed to approving any of these therapies on biomarker lowering alone. The phase 3 trials are large, long-event cardiovascular outcomes studies, designed to read out on hard MACE: heart attack, stroke, and cardiovascular death. The FDA's earlier acceptance of LDL as a surrogate endpoint for PCSK9 inhibitors is the optimistic precedent. Whether the same pathway opens for lipoprotein(a) in primary-prevention patients is a separate decision the readout will not answer.

There is a second-order problem on the demand side. Most U.S. adults have never had their lipoprotein(a) measured, because routine lipid panels do not include it and clinical guidelines still push the test toward people with a family history of early cardiovascular disease, as UCHealth's clinical explainer on the Lp(a) trials lays out. The 1-in-5 prevalence is the population at risk. The testing gap is the population an eventual drug launch would have to reach. If the phase 3 trials are positive, the first clinical challenge will not be choosing among four molecules. It will be finding the carriers.

The phase 3 readouts are expected to arrive in a compressed window, with Lp(a)HORIZON among the trials closest to an event-driven readout. The headline that matters will not be which company crosses the line first. It will be whether lowering a particle 1 in 5 adults inherit actually moves the number that counts: heart attacks.