Low-Density Lipoprotein (LDL) Apheresis

Complementary role of evinacumab in combination with lipoprotein apheresis in patients with homozygous familial hypercholesterolemia

Patients with homozygous familial hypercholesterolemia (FH) have severe hypercholesterolemia from birth and if untreated may experience very early onset of coronary artery disease in childhood or young adulthood with an aggressive course resulting in early death. Early initiation of aggressive low-density lipoprotein cholesterol (LDL-C) lowering is the mainstay of treatment, which requires the use of a multidrug treatment regimen, often in combination with lipoprotein apheresis, but LDL-C goal achievement is frequently unattainable due to the severity of baseline hypercholesterolemia and hyporesponsiveness to many LDL-C-lowering medications. Evinacumab, a monoclonal antibody that sequesters angiopoietin-like 3 protein and lowers LDL-C by an average of 49% in patients with homozygous FH, was approved by the Food and Drug Administration in February 2021 and is a major advance in treatment of these high-risk patients. In this report, we describe the complementary role of evinacumab in combination with lipoprotein apheresis in two patients with homozygous FH.

Modern Management of Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is a common genetic disorder that can manifest clinically as both the severe homozygous (HoFH) form that often presents in childhood and the commoner heterozygous (HeFH) form that is typically identified in adults. The majority of genetic causes are due to defects in low-density lipoprotein (LDL) receptor synthesis and action. Until recently, it was exceedingly difficult to achieve the goal of a 50% reduction in LDL-cholesterol or LDL-C < 70-100 in these patients. Established therapies include statins, niacin, bile-acid sequestrants, and ezetimibe in various combinations. The recent advent of monoclonal antibodies to PCSK9 (evolocumab and alirocumab) has revolutionized the management of FH and results in a substantial reduction in LDL-C and also reductions in Lp(a). In addition, the previous ushering in of antisense therapy against apoB (mipomersen) and inhibition of microsomal transfer protein (lomitapide) for use in HoFH greatly enhanced our ability to manage refractory hypercholesterolemia in these patients. Hence, the therapeutic landscape for this common disorder has changed dramatically for these patients, with a strong promise for a reduction in cardiovascular events.