Evinacumab for Homozygous Familial Hypercholesterolemia: The Italian Cohort of the ELIPSE HoFH Study

Introduction: Homozygous familial hypercholesterolemia (HoFH) is a severe rare genetic disorder characterized by elevated plasma low-density lipoprotein (LDL) cholesterol levels. Here, we report data from the Italian cohort of the Evinacumab Lipid Studies in Patients with Homozygous Familial Hypercholesterolemia (ELIPSE HoFH) trial. Methods: ELIPSE HoFH was conducted at 30 sites in 11 countries, with 2-10 patients enrolled per country. The study included patients aged ≥ 12 years with LDL cholesterol ≥ 70 mg/dl (1.8 mmol per liter) at screening despite stable maximally tolerated lipid-lowering therapy. Patients were randomly assigned evinacumab (15 mg/kg every 4 weeks) or matching placebo for 24 weeks, with an option for a 24-week open-label extension or follow-up period thereafter. The Italian cohort included seven patients assigned to evinacumab. Results: Five patients (3 males and 2 females) received evinacumab and were included in this report. Substantial and consistent reductions in LDL cholesterol from baseline levels were observed in all patients at all follow-up time points. Overall, an 84.5% decrease in median (range) LDL cholesterol was observed, from 323 (203-587) mg/dl in 2016 to 50.0 (13-103) mg/dl (P = 0.043) in 2019, with LDL cholesterol levels stable through 2023. Total cholesterol, high-density lipoprotein (HDL) cholesterol, non-HDL cholesterol, and triglycerides decreased markedly over time. Evinacumab was well tolerated, with no treatment-related adverse events reported. Conclusion: Evinacumab substantially lowered LDL cholesterol levels in patients with HoFH regardless of the degree of LDL receptor function, with low levels sustained over 5 years of follow-up. Trial registration: ClinicalTrials.gov identifier NCT03399786 registered 16 January 2018.