This study investigates the effects of olpasiran in individuals diagnosed with atherosclerotic cardiovascular disease, a condition where plaque builds up in the arteries, and elevated lipoprotein (a), which is a specific type of fatty protein found in the blood. The purpose of the study is to compare the impact of the study drug against a placebo on the risk of major heart-related issues. These issues include coronary heart disease death, myocardial infarction, or the need for urgent coronary revascularization, which is a procedure used to restore blood flow to the heart.

Participants will be assigned to receive either olpasiran or a placebo through a subcutaneous injection, which means the medication is delivered into the fatty tissue just under the skin. During the study, researchers will monitor for various health events such as ischemic stroke, which is a blockage of blood flow to the brain, and cardiovascular death. The study will also track changes in the levels of lipoprotein (a) in the blood over time to see how the treatment affects this substance.