PCSK9 inhibitors
PCSK9 inhibitors switch off PCSK9, a liver protein that destroys the receptors the liver uses to pull LDL cholesterol out of the blood, so more receptors stay in service and LDL cholesterol falls. Antibodies and a small interfering RNA are used for high LDL cholesterol that statins alone do not control, including familial hypercholesterolemia, and gene-editing versions that aim to switch the gene off for good are in trials. Injection-site reactions are common with the approved drugs, and the gene-editing versions have caused infusion reactions and short-lived rises in liver enzymes in early trials. The key safety point for gene editing is that a single dose changes liver DNA permanently, so its long-term effects can only be learned over years of follow-up.