Beyond the Statins: An Overview of PCSK9 Inhibitor Antibodies
February 22, 2021
Monoclonal antibodies are notoriously expensive. Whether for the treatment of rheumatoid arthritis or multiple sclerosis, the costs are incredibly high. I smile when I think of these drugs because they were first introduced at around $1,200 per month.
Due to poor sales because of formulary coverage, both companies reduced the price of these drugs by 60%. It shows that monoclonal antibody therapy for COMMON diseases needs to be reasonably priced. We are seeing more of these drugs being used, thanks to decreased costs. They are highly efficacious, but certainly do not take the place of statin therapy for most patients, with a cost of around $10 per month.
PCSK9 (Proprotein Convertase Subtilisin Kexin Type 9) Inhibitor Antibodies
(Both drugs approved in 2015)
HOW THEY WORK: The PCSK9 protein interferes with the clearance of LDL-C from the blood. LDL receptors on liver cells remove LDL-C from the blood by binding it and then moving it into the cell for elimination. The lipid-free receptors then return to the surface of the cell. When PCSK9 binds to the LDL receptor, however, the receptor is unable to re-emerge on to the cell surface to remove more LDL-C, which then remains in the blood. By inhibiting the PCSK9 protein, PCSK9 inhibitors essentially improve the liver’s ability to recycle LDL receptors, resulting in a greater number of receptors on the cell surface and enabling more LDL-C to be removed from circulation.
BENEFITS:
- They can lower LDL-C by as much as 60% in patients on statin therapy.
- Reductions in the rates of stroke or myocardial infarction by 50%.
- Lowers triglyceride levels by 12 to 31 percent
- Slight increase in high density lipoprotein cholesterol by 5 to 9 percent
Alirocumab (Praluent®): (approx. $500/month): Indicated as adjunct to diet and maximally tolerated statin therapy for the treatment of adults with heterozygous familial hypercholesterolemia or clinical atherosclerotic cardiovascular disease, who require additional lowering of LDL- C
Storage: keep in a refrigerator at 36°F to 46°F in the outer carton in order to protect from light. Warm up to room temperature before injection. Don’t exceed 24 hours of time out of refrigerator. May take up to 20 seconds for injection to be complete.
Dose: 75mg SQ every 2 weeks. This is usually enough to achieve max lowering of LDL-C. Maximum dose is 150mg every 2 weeks. Available as pre-filled single dose pens, 75mg or 150mg.
Evolocumab (Repatha®): (approx. $500/month) is used along with diet and maximally tolerated statin therapy for adults with heterozygous familial hypercholesterolemia, (an inherited condition that causes high levels of LDL), or atherosclerotic heart or blood vessel problems, who need additional LDL lowering.
Keep refrigerated. May be stored at room temperature for up to 30 days.
Dose: Primary hyperlipidemia with established clinical atherosclerotic CVD or heterozygous familial hypercholesterolemia: 140 mg every 2 weeks or 420 mg once monthly in abdomen, thigh, or upper arm.
For both products “maximally tolerated statin therapy” can be interpreted as no statin at all if patients can’t tolerate statins.
Have a Great Day on the bench!
