Discordant response of low-density lipoprotein cholesterol and lipoprotein(a) levels to monoclonal antibodies targeting proprotein convertase subtilisin/kexin type 9.

Clinical trials testing proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) have demonstrated an unanticipated but significant lipoprotein (a) (Lp(a))-lowering effect, on the order of 25% to 30%. Although the 50% to 60% reduction in low-density lipoprotein (LDL)-cholesterol (LDL-C) achieved by PCSK9i is mediated through its effect on LDL receptor (LDLR) preservation, the mechanism for Lp(a) lowering is unknown. We sought to characterize the degree of concordance between LDL-C and Lp(a) lowering because of PCSK9i in a standard of care patient cohort. Participants were selected from our Center for Preventive Cardiology, an outpatient referral center in a tertiary academic medical center. Subjects were included in this study if they had (1) at least 1 measurement of LDL-C and Lp(a) before and after initiation of the PCSK9i; (2) baseline Lp(a) > 10 mg/dL; and (3) continued adherence to PCSK9i therapy. They were excluded if (1) they were undergoing LDL apheresis; (2) pre- or post-PCSK9i LDL-C or Lp(a) laboratory values were censored; or (3) subjects discontinued other lipid-modifying therapies. In total, 103 subjects were identified as taking a PCSK9i and 26 met all inclusion and exclusion criteria. Concordant response to therapy was defined as an LDL-C reduction >35% and an Lp(a) reduction >10%. The cohort consisted of 26 subjects (15 females, 11 males, mean age 63 ± 12 years). Baseline mean LDL-C and median Lp(a) levels were 167.4 ± 72 mg/dL and 81 mg/dL (interquartile range 38-136 mg/dL), respectively. The average percent reductions in LDL-C and Lp(a) were 52.8% (47.0-58.6) and 20.2% (12.2-28.1). The correlation between %LDL and %Lp(a) reduction was moderate, with a Spearman's correlation of 0.56 (P < .01). All subjects except for 1 had a protocol-appropriate LDL-C response to therapy. However, only 16 of the 26 (62%; 95% confidence interval 41%-82%) subjects had a protocol-concordant Lp(a) response. Although some subjects demonstrated negligible Lp(a) reduction associated with PCSK9i, there were some whose Lp(a) decreased as much as 60%. In this standard-of-care setting, we demonstrate moderate correlation but large discordance (∼40%) in these 2 lipid fractions in response to PCSK9i. The results suggest that pathways beyond the LDLR are responsible for Lp(a) lowering and indicate that PCSK9i have the potential to significantly lower Lp(a) in select patients, although confirmation in larger multicenter studies is required.

Edmiston JB ，Brooks N ，Tavori H ，Minnier J ，Duell B ，Purnell JQ ，Kaufman T ，Wojcik C ，Voros S ，Fazio S ，Shapiro MD ... -  《-》

Lipoprotein Apheresis and Proprotein Convertase Subtilisin/Kexin Type 9 Inhibitors in Patients With Heterozygous Familial Hypercholesterolemia: A One Center Study.

Kolovou V ，Katsiki N ，Makrygiannis S ，Mavrogieni S ，Karampetsou N ，Manolis A ，Melidonis A ，Mikhailidis DP ，Kolovou GD ... -  《-》

Relationship Between Low-Density Lipoprotein Cholesterol and Lipoprotein(a) Lowering in Response to PCSK9 Inhibition With Evolocumab.

Shapiro MD ，Minnier J ，Tavori H ，Kassahun H ，Flower A ，Somaratne R ，Fazio S ... -  《Journal of the American Heart Association》

Impact of PCSK9 inhibitors on plasma lipoprotein(a) concentrations with or without a background of niacin therapy.

Lipoprotein(a) [Lp(a)] is an atherogenic lipoprotein associated with atherosclerotic cardiovascular disease. Niacin and proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) both lower Lp(a). The objective of the study was to determine if addition of PCSK9i to background niacin therapy further lowers Lp(a). This study is a retrospective analysis of patients who met the following inclusion criteria: initiated PCSK9i therapy, had Lp(a) measurements before and after initiation of PCSK9i, and for the combination therapy group, PCSK9i was added on top of baseline niacin monotherapy. Of the 150 patients included in this study, 136 were on monotherapy (PCSK9i) and 14 were on combination therapy (niacin + PCSK9i). Lp(a) values were assessed in both groups before and after the addition of PCSK9i. Median percent and absolute Lp(a) reductions in the niacin + PCSK9i combination therapy group were -15.3% (interquartile range [IQR] -31.8, -1) and -9 mg/dL (IQR -37.2, -0.5), respectively, from a baseline Lp(a) of 95 mg/dL (IQR 20.5, 171). These reductions were statistically significant or nearly so (P = .04 and P = .05, respectively). Median percent and absolute Lp(a) reductions in the PCSK9i monotherapy group were -17.3% (IQR -34.4, 0) and -6 mg/dL (IQR -16, 0), respectively, from a baseline Lp(a) of 39.5 mg/dL (IQR 15, 117.5). There was no difference in median percent and absolute change in Lp(a) between monotherapy and combination therapy groups (P = .84 and P = .54, respectively). Our study demonstrates that the addition of PCSK9i to background of niacin therapy is associated with ∼15% reduction in Lp(a) beyond that achieved with background niacin monotherapy.

Warden BA ，Minnier J ，Watts GF ，Fazio S ，Shapiro MD ... -  《-》

AMG145, a monoclonal antibody against proprotein convertase subtilisin kexin type 9, significantly reduces lipoprotein(a) in hypercholesterolemic patients receiving statin therapy: an analysis from the LDL-C Assessment with Proprotein Convertase Subtilisi

Desai NR ，Kohli P ，Giugliano RP ，O'Donoghue ML ，Somaratne R ，Zhou J ，Hoffman EB ，Huang F ，Rogers WJ ，Wasserman SM ，Scott R ，Sabatine MS ... -  《-》