Real-World Efficacy of Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors (PCSK9i) in Heterozygous Familial Hypercholesterolemia Patients Referred for Lipoprotein Apheresis

Background: A small proportion of familial hypercholesterolemia (FH) patients can adequately control this condition, although achieving the recommended targets for low-density lipoprotein cholesterol (LDL-c) levels remains a challenge. Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are new and potent lipid-lowering drugs. However, there is scarce literature on real-world data about their use in patients with FH. Material/Methods: We examined the reduction in LDL-c levels from the baseline, after PCSK9i initiation in heterozygous familial hypercholesterolemia patients referred for lipoprotein apheresis in our regional lipid clinic. The study was conducted from March 2018 to September 2019, the period immediately after PCSK9i reimbursement was available in France. PCSK9i was added on top of the patients' maximal tolerated lipid-lowering regimens. Results: The study had 123 patients with heterozygous FH. The mean age of the patients was 59 +/- 11 years. The mean baseline LDL-c for all the participants was 277 +/- 78 mg/dl. It was 283 +/- 81 mg/dl in the PCSK9i monotherapy group (n=83), 247 +/- 68 mg/dl in the PCSK9i plus ezetimibe group (n=12), and 264 +/- 78 mg/dl in the PCSK9i plus statin and ezetimibe group (n=28). The mean decrease observed in the LDL-c level from baseline was 136 +/- 70 mg/dl (n=123), 125 +/- 60 mg/dl (n=83), 103 +/- 77 mg/dl (n=12), and 175 +/- 70 mg/dl (n=28), respectively. Conclusions: An overall reduction of 49.1% from the baseline LDL-c was observed in the heterozygous FH population after PCSK9i initiation in a real-world experience. The group treated with PCSK9i ezetimibe plus statin showed further reduction of their LDL-c levels with a better responder rate, achieving the target 50% reduction in LDL-c from the baseline.