Abstract : Evolocumab is a fully human monoclonal antibody (mAb) targeting ProProtein Convertase Subtilisin/Kexin 9 (PCSK9). PCSK9 is a circulating enzyme secreted by the liver and plays a key role in the LDL-Receptors (LDL-R) turnover. Binding of PCSK9 on the extracellular part of LDL-R is responsible for its degradation in the lysosome instead of its recycling to the cell surface, thereby producing a reduction in the number of LDL-R on the cell surface, a decreased LDL-C uptake and increased levels of LDL-C. Inhibiting PCSK9 is a new way to markedly reduce LDL-C. The development of mAbs that bind the extracellular PCSK9 and prevent its interaction with LDL-R is the most advanced and tested approach to PCSK9 inhibition to date. The clinical efficacy and safety of evolocumab have been studied in a number of controlled trials versus placebo or versus active comparator (ézétimibe) during 12 to 76 weeks. Added on statin, evolocumab reduced LDL-C up to 50 to 60 % from baseline. Evolocumab also reduced LCL-C in monotherapy in statin-intolerant patients. Evolocumab also significally reduced total cholesterol, non-HDL cholesterol, apoprotein B and lipoprotein(a). Safety and tolerance were good. Evolocumab is commercialized under the trade name Repatha® and administrated subcutaneously at the dose of 140 mg every 2 weeks or 420 mg once per month. Repatha® is approved in Belgium, with conditions, for the treatment of hypercholesterolemia in patients with heterozygous (HFe) and homozygous (HFo) familial hypercholesterolemia.