Heterozygous familial hypercholesterolemia: the first challenge for anti-PCSK9 monoclonal antibodies

Heterozygous familial hypercholesterolemia (HeFH) is characterized by a prevalence of 1/200 (higher than 1/500 as previously estimated): based on this updated prevalence, in Italy there are about 250-300 000 subjects with HeFH. Patients with HeFH are significantly underdiagnosed (in Italy only 4-5% of total estimated HeFH are properly diagnosed), undertreated (only 1 in 5 to 10 HeFH at target for LDL-cholesterol), and characterized by a high or very high cardiovascular risk. There are simple criteria for the diagnosis of familial hypercholesterolemia such as those issued by the Dutch Lipid Clinic Network (DLCN), easy to implement both in general practice as well as by the specialists. Genetic diagnosis is strongly suggested to support the diagnosis of familial hypercholesterolemia. Lipid-lowering therapy with high dose of highly effective statins, often associated with ezetimibe, should be initiated immediately at diagnosis in adults and at age 8-10 years in childhood. Evolocumab and alirocumab are monoclonal antibodies against PCSK9. They are a highly innovative lipid-lowering approach, characterized by a good safety profile and a remarkable LDL-cholesterol lowering effect when associated with the maximally tolerated dose of statins plus ezetimibe. Studies with alirocumab and evolocumab in HeFH patients show a further LDL-cholesterol decrease by 50-60% vs intensive lipid-lowering therapy with statins ± ezetimibe, with 70-80% of HeFH patients achieving their LDL-cholesterol targets.