LDLR and homozygous familial hypercholesterolemia: This 2-part multicenter study included 13 patients ≥12 to <18 years of age with a genetic diagnosis of HoFH (excluding LDL [low-density lipoprotein] receptor [LDLR] null/null genotypes) and elevated LDL-C levels (>130 mg/dL) on maximally tolerated statin treatment, with or without other lipid-lowering therapies.