Multimodal Therapy Achieves Secondary Prevention LDL-C Targets in LDL-Receptor Null Homozygous Familial Hypercholesterolemia.

backgroundHomozygous familial hypercholesterolemia is a rare condition most commonly associated with pathogenic variants in the LDLR gene that leads to mortality before age 20 if not treated. CASE SUMMARY: A 4-year-old boy of Lebanese origin with multiple skin xanthomas was found to have untreated low-density lipoprotein cholesterol (LDL-C) of 1005 mg/dL (26 mM). Gene analysis revealed biallelic identical LDLR variants with <2% residual LDLR activity (LDLR-null). DISCUSSION: With combination therapy including maximum dose rosuvastatin, ezetimibe, plasma exchange, lomitapide, and evinacumab, guideline-recommended LDL-C of <70 mg/dL (1.8 mM) was achieved for secondary prevention of coronary disease. With this combined treatment, there has been no progression of his premature coronary heart disease. TAKE-HOME MESSAGES: Effective treatment of homozygous familial hypercholesterolemia requires multimodal lipid-lowering therapies. With currently available treatments it is possible to achieve previously unattainable lowering of LDL-C to prevent vascular disease and the need for liver transplantation.