Clinical Updates in Alirocumab Injection

Alirocumab (Praluent; Regeneron), is a PCSK9 inhibitor indicated for the treatment of adults with heterozygous familiar hypercholesterolemia (HeFH) or atherosclerotic cardiovascular disease, as adjunct to diet and maximal statin therapy. This is a medication for those that need or require additional lowering of low-density lipoprotein cholesterol (LDL-C) levels in the body.¹

Alirocumab comes in a 75 mg/ml dosage as well as 150 mg/ml solution, in single dose pre-filled pens. The recommended starting dose for this medication is 75 mg once every 2 weeks. This medication is given subcutaneously and, for patients that need less frequent dosing, it is recommended to give 300 mg once every 4 weeks. This medication can be administered in the abdomen, upper arm, or thigh.¹

Illustration of cholesterol | image credit: Kien | stock.adobe.com

Some patients may experience hypersensitivity reactions such as pruritis, rash, or urticaria, and adverse effects can include nasopharyngitis, injection site reactions, and influenza-like symptoms. It is important for those taking this medication for the first time to be aware of these adverse effects and watch out for any reactions. Pharmacists should provide education to patients and explain both the benefits and potential adverse effects of this medication.¹

Alirocumab binds to the low-density lipoprotein receptors on the surface of the hepatocytes, resulting in the promotion of the lipoprotein receptors’ degradation within the liver. By inhibiting the binding of PCSK9 to LDL receptors, alirocumab increases the number of LDL receptors available in the body to clear more LDLs, therefore lowering the LDL cholesterol levels in the blood.¹

The maximum suppression of PCSK9s occurs around 4 to 8 hours after the injection and maximum serum concentration is reached within 3 to 7 days. The absolute bioavailability of alirocumab is about 85% after the injection. Because the monoclonal antibodies are not known to be cleared renally, renal function or monitoring is not needed for this medication. The median half-life of alirocumab is reduced to 12 days when it is administered with a statin medication, although this reduction is not clinically meaningful.¹

Alirocumab was investigated in 5 double blind, placebo-controlled trials enrolling approximately 3499 patients. Three of the 5 trials enrolled patients with HeFH. All patients in the studies were on the highest tolerated dose of statins. In some of these studies, the patients’ initial dose was 75 mg every 2 weeks, followed by 150 mg every 2 weeks. Of these studies, only 2 used the higher dose of alirocumab and administered 150 mg every 2 weeks. An additional study was conducted which administered a 300 mg dose every 4 weeks, 75 mg every 2 weeks, or placebo, to about 547 patients.¹

This medication should be refrigerated at 36°F to 46°F (2°C to 8°C) in the original carton in order to protect it from light. The medication can be kept at room temperature up to 77°F (25°C) for a maximum of 30 days in the original carton.¹

Alirocumab can help reduce the risk of heart attack, stroke, or certain types of chest pain and unstable angina that require hospitalizations in adults.² With this medication on the market and FDA approved as of 2015, patients with high, uncontrolled LDL-C levels have more options to get their LDL cholesterol under control.

References

1. Praluent. Prescribing information. FDA. Updated July 2017. Accessed September 4, 2024. https://www.accessdata.fda.gov/drugsatfda_docs/label/2017/125559s002lbl.pdf

2. Praluent. Accessed September 4, 2024. https://www.praluent.com/s/how-to-use-praluent