Effect of ezetimibe coadministered with statins in genotype-confirmed heterozygous FH patients.
We investigated the effect of statins and statins plus ezetimibe in 65 FH heterozygotes carrying LDLR-defective or LDLR-negative mutations as well as the effect of ezetimibe monotherapy in 50 hypercholesterolemic (HCH) patients intolerant to statins. PCSK9 and NPC1L1 genes were analysed to assess the role of genetic variants in response to therapy. In FH patients combined therapy reduced LDL-C by 57%, irrespective of the type of LDLR mutation. The additional decrease of plasma LDL-C induced by ezetimibe showed wide inter-individual variability (from -39% to -4.7%) and was negatively correlated with percent LDL-C decrease due to statin alone (r=-0.713, P<0.001). The variable response to statins was not due to PCSK9 gene variants associated with statin hyper-sensitivity. The highest response to ezetimibe was observed in a carrier of R174H substitution in NPC1L1, which had been found to be associated with high cholesterol absorption. In HCH patients, ezetimibe monotherapy induced a variable decrease of plasma LDL-C (from -47.7% to -13.4%). To investigate this variability, we sequenced NPC1L1 gene in patients with the highest and the lowest response to ezetimibe. This analysis showed a higher prevalence of the G allele of the c.816 C>G polymorphism (L272L) in hyper-responders, an observation confirmed also in FH patients hyper-responders to ezetimibe. In both FH and HCH patients, the G allele carriers tended to have a higher LDL-C reduction in response to ezetimibe. These observations suggest that in FH heterozygotes LDL-C reduction following combined therapy reflects a complex interplay between hepatic synthesis and intestinal absorption of cholesterol.
Pisciotta
Livia
L
Department of Internal Medicine, University of Genoa, Viale Benedetto XV 6, I-16132 Genoa, Italy.
Fasano
Tommaso
T
Bellocchio
Antonella
A
Bocchi
Letizia
L
Sallo
Raffaella
R
Fresa
Raffaele
R
Colangeli
Isabella
I
Cantafora
Alfredo
A
Calandra
Sebastiano
S
Bertolini
Stefano
S
D000328:Adult; D000368:Aged; D000924:Anticholesteremic Agents / Q000494:pharmacology*; D001384:Azetidines / Q000494:pharmacology*; D008078:Cholesterol, LDL / Q000187:drug effects*; D015331:Cohort Studies; D004359:Drug Therapy, Combination; D000069438:Ezetimibe; D005260:Female; D005838:Genotype; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000494:pharmacology*; D006938:Hyperlipoproteinemia Type II / Q000188:drug therapy* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009154:Mutation; D000071449:Proprotein Convertase 9; D043484:Proprotein Convertases; D011973:Receptors, LDL / Q000235:genetics*; D012697:Serine Endopeptidases / Q000235:genetics
D000924:Anticholesteremic Agents; D001384:Azetidines; D008078:Cholesterol, LDL; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D011973:Receptors, LDL; C472125:PCSK9 protein, human; D000071449:Proprotein Convertase 9; D043484:Proprotein Convertases; D012697:Serine Endopeptidases; D000069438:Ezetimibe