Positive results have been reported from a phase 3 study evaluating evolocumab (Repatha, Amgen) in patients who were receiving apheresis to reduce low-density lipoprotein cholesterol (LDL-C) levels. The study met its primary endpoint, demonstrating that treatment with evolocumab significantly reduced the need for LDL-C apheresis in adult patients. The study also met its secondary endpoints of the percent change from baseline to week 4 in LDL-C, in non–high-density lipoprotein cholesterol (non-HDL-C), and in the total cholesterol/HDL-C ratio.
Thirty-nine adult patients with LDL-C levels of 100 mg/dL to 190 mg/dL despite regular weekly or biweekly apheresis plus statin therapy (if tolerated) were randomly assigned to receive evolocumab subcutaneously every two weeks or to continue LDL-C apheresis (every one or two weeks, according to their schedule before entering the study) for the first six weeks. Beginning at week 6, all of the patients were given evolocumab.
Evolocumab is a human monoclonal antibody that inhibits proprotein convertase subtilisin/kexin type 9 (PCSK9). Evolocumab binds to circulating PCSK9 and inhibits it from binding to the LDL receptor (LDLR), thereby preventing PCSK9-mediated LDLR degradation and permitting LDLR to recycle back to the liver cell surface. By inhibiting the binding of PCSK9 to LDLR, evolocumab increases the number of LDLRs that are available to clear LDL from the blood, thereby lowering LDL-C levels.
Evolocumab is approved as an adjunct to diet and maximally tolerated statin therapy for the treatment of adults with heterozygous familial hypercholesterolemia (HeFH) or clinical atherosclerotic cardiovascular disease (ASCVD) who require additional lowering of LDL-C. It is also indicated with other LDL-lowering therapies (e.g., statins, ezetimibe, and LDL apheresis) for patients with homozygous familial hypercholesterolemia (HoFH) who require additional lowering of LDL-C.
Source: Amgen; March 13, 2017.