PCSK9 inhibitors and treatment targets: an audit-based evaluation of a specialist lipid clinic

Abstract

Background: Trial evidence for lower LDL cholesterol (LDL-C) treatment targets for cardiovascular benefit were incorporated into recent European Society of Cardiology/European Atherosclerosis Society and NICE guidelines. Treatment targets are LDL-C <1.4mmol/L, LDL-C <1.8mmol/L and ≥50% LDL-C reduction for atherosclerotic cardiovascular disease (ASCVD) and/or Familial Hypercholesterolaemia (FH). There is limited real-world evidence of proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9is), with enhanced LDL-C lowering, achieving these targets. Aims: To assess attainment of guideline LDL-C targets using PCSK9is ± oral lipid-lowering therapies (LLT) in ASCVD and/or FH. Methods: Clinic-based audit using retrospective case-note review of adults prescribed PCSK9is. Anonymised data were collected before and after PCSK9i initiation. Standards were attainment of LDL-C <1.8mmol/L, LDL-C <1.4mmol/L and ≥50% LDL-C reduction. Results: Fifty-five patients (mean age 60.8 years) receiving PCSK9is (35% monotherapy; median treatment duration 1.5 years) were identified (ASCVD, n=50; FH, n=18). Target attainment was 80% for ≥50% LDL-C reduction, 46% for LDL-C <1.8mmol/L and 24% for LDL-C <1.4mmol/L. Greater attainment of these targets occurred with ≥2 additional LLTs versus one additional LLT or PCSK9i monotherapy. Conclusion: Most ASCVD and/or FH patients achieved ≥50% LDL-C reductions with PCSK9is. Fewer achieved LDL-C <1.8mmol/L and <1.4mmol/L targets. PCSK9is in combination with other LLT achieved targets more often compared to PCSK9i monotherapy. Achievement of recommended lipid targets may require greater use of PCSK9i combination therapies.