PCSK9 Inhibitors Explained: All 5 Options

PCSK9 is a liver protein that breaks down LDL receptors, which pull LDL cholesterol out of your blood. More PCSK9 means fewer receptors and more LDL circulating. These medicines block or reduce PCSK9, so your liver keeps more receptors active and clears more LDL.

A PCSK9 inhibitor is a different class from a statin. Statins slow the liver's cholesterol production. The two add together, and a PCSK9 inhibitor can also be used without a statin.

Five are available in the US as of October 2026, and all five lower LDL by a broadly similar amount in their main trials:

Yes, for the two with completed outcomes trials. FOURIER followed over 27,000 people with established cardiovascular disease already on a statin. Adding evolocumab lowered LDL-C by 59% (median 92 to 30 mg/dL) and reduced the combined risk of cardiovascular death, heart attack, stroke, hospitalization for unstable angina, or an artery-opening procedure by 15%.

In the GLAGOV imaging trial, plaque in the coronary arteries regressed in 64% of people on evolocumab versus 47% on placebo. Leqvio, Lipfendra and Lerochol are approved based on LDL lowering. Their outcomes trials haven't reported yet.

Side effects are usually mild. With the injectables, the most common are injection-site reactions (redness, pain or bruising) and cold-like symptoms. In FOURIER, the only adverse event more common than placebo was injection-site reactions (2.1% vs 1.6%), with no increase in new diabetes or neurocognitive events.

The EBBINGHAUS substudy tested memory and thinking in 1,204 FOURIER participants over a median of 19 months and found no difference from placebo. With Lipfendra, diarrhea and dizziness were slightly more common than placebo in people with familial hypercholesterolemia.

The bigger practical downsides are cost, insurance paperwork, the injections themselves, and outcomes evidence that is still coming for the newest three.

Clinicians typically consider one for people whose LDL-C or ApoB stays above target on a maximum-tolerated statin (with or without ezetimibe), people who can't take statins at any meaningful dose, people with familial hypercholesterolemia, and people with established cardiovascular disease and persistently high LDL-C.

The 2026 ACC/AHA guideline sets an LDL-C goal under 70 mg/dL for people with cardiovascular disease and under 55 mg/dL at very high risk. When LDL stays above goal on a statin, it says adding ezetimibe and/or a PCSK9 inhibitor should be implemented without delay. Ask your clinician whether you fit.

Many insurers require documented trials of a statin, and often ezetimibe, before paying. This step therapy and prior authorization applies even to people who clearly meet the clinical criteria.

A request listing the diagnosis, a recent lipid panel, and the exact statins, doses and dates you tried is far easier to approve. A first denial often means the plan needs more paperwork, so answer exactly what the letter asks.