PCSK9 and familial hypercholesterolemia: Moreover, because proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors effectively lower serum LDL-C concentration, reduce the Lp(a) level by about 30%, and may also enhance the antiviral action of interferon in patients with hypercholesterolemia, the use of these inhibitors could be considered in hospitalized pediatric FH patients with COVID-19, particularly those with HoFH, if not already in use (25–27).