Hyperlipidemia patients carrying LDLR splicing mutation c.1187-2A>G respond favorably to rosuvastatin and PCSK9 inhibitor evolocumab.

ABSTRACT

Mutations in the LDL receptor gene LDLR cause familial hypercholesterolemia (FH); however, the pharmacogenomics of specific LDLR mutations remains poorly understood. The goals of this study were to identify the genetic cause of a three-generation Chinese family affected with autosomal dominant FH, and to investigate the response of FH patients in the family to statin and evolocumab. Whole exome sequencing of the FH family with four patients and six unaffected members identified a heterozygous splicing mutation (c.1187-2A>G) in LDLR. The mutation co-segregated with FH in the family, providing strong genetic evidence to support its pathogenicity. The proband was a 48-year-old male FH patient who had an acute myocardial infarction (MI) and ventricular fibrillation (VF), and showed LDL-C of 5.23 mmol/L. A combination of life style modifications on food and exercise and treatment with rosuvastatin reduced his LDL-C to 2.05-2.80 mmol/L. Addition of ezetimibe did not improve rosuvastatin therapy, but addition of evolocumab further reduced LDL-C by 70% to 0.7 mmol/L at the first time and by 67% to 1.31 mmol/L at the second time. Rosuvastatin also reduced LDL-C for proband's father and sister by 40% and 43-63%, respectively. Lovastatin alone or addition to rosuvastatin treatment did not have any effect on LDL-C for the proband and his son. Both patients carry ApoE 3/4 genotype and SLCO1B1 rs4149056 TT genotype. These results suggest that combined treatment with rosuvastatin (but not lovastatin or ezetimibe) and evolocumab can control LDL-C to meet the LDL-C treatment goal for patients with LDLR splicing mutation c.1187-2A>G.