Dramatic response to Evinacumab in a North Indian girl with homozygous familial hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH) is a rare inherited disorder of lipoprotein metabolism associated with significant morbidity and early mortality. The conventional management with lipid-lowering drugs and lipoprotein apheresis is unable to consistently achieve guidelines recommended low-density lipoprotein cholesterol (LDL-C). We aim to describe the efficacy of Evinacumab, a recently approved monoclonal antibody, in lowering LDL-C in an Indian girl with HoFH.

A 16-year-old girl was diagnosed with HoFH at age two years after the appearance of cutaneous and tendo-calcaneus xanthomas. Genetic testing revealed a pathogenic homozygous deletion in the LDL receptor (LDLR) gene. Despite lifestyle measures, a low-fat diet, and maximum doses of atorvastatin and ezetimibe, her average LDL-C level remained 320.3 mg/dL over the past decade. Her caregivers did not accept LDL-apheresis. She also did not respond to Evolocumab therapy. The patient developed progressive calcific aortic stenosis and concentric left ventricular hypertrophy, necessitating aortic valve replacement surgery at age 16 years. The recent addition of Evinacumab to her lipid-lowering drug regimen, resulted in a significant LDL-C reduction of 76.16 %, bringing levels down to 82 mg/dL. These levels were sustained over the last four months.

Evinacumab offers a promising option for managing high-risk and difficult-to-treat HoFH patients. This is the first Indian child receiving Evinacumab for HoFH.