PCSK9 and familial hypercholesterolemia: A prior report by Shapiro et al. [19] evaluated potential causes of hyporesponsiveness among 17 adults with cardiovascular disease (n = 14) and/or familial hypercholesterolemia (n = 9) treated with a PCSK9 inhibitor (12 patients received alirocumab and 5 patients received evolocumab).