Efficacy and safety of mipomersen, an antisense inhibitor of apolipoprotein B, in hypercholesterolemic subjects receiving stable statin therapy.
OBJECTIVE
The aim of this study was to evaluate the efficacy and safety of mipomersen in hypercholesterolemic subjects taking stable statin therapy.


BACKGROUND
Mipomersen is an apolipoprotein (apo) B synthesis inhibitor that has demonstrated significant reductions in apo B and low-density lipoprotein (LDL) cholesterol in Phase 1 clinical trials in healthy volunteers.


METHODS
A randomized, placebo-controlled, dose-escalation Phase 2 study was designed to evaluate the effects of mipomersen in hypercholesterolemic subjects taking stable statin therapy. Seventy-four subjects were enrolled sequentially into 1 of 6 dose cohorts at a 4:1 (active/placebo) ratio. Subjects received 7 doses of 30 to 400 mg over 5 weeks in the first 5 cohorts and 15 doses of 200 mg over 13 weeks in the sixth cohort. Pre-specified end points included percentage change from baseline in apo B and LDL cholesterol. Safety was assessed with laboratory test results and by the incidence and severity of adverse events.


RESULTS
The apo B and LDL cholesterol were reduced by 19% to 54% and 21% to 52%, respectively, at doses of 100 mg/week mipomersen and higher in the 5-week treatment cohorts. Efficacy seemed to increase upon treatment for 13 weeks at a dose of 200 mg/week. Injection site reactions (mild to moderate erythema [90%]) and hepatic transaminase increases (17%) were the most common adverse events, leading to discontinuation in 2 subjects and 1 subject, respectively. In the 13-week treatment cohort, 5 of 10 subjects (50%) had elevations >or=3x the upper limit of normal, 4 of which persisted on 2 consecutive occasions.


CONCLUSIONS
Mipomersen might hold promise for treatment of patients not reaching target LDL cholesterol levels on stable statin therapy. Further studies are needed to address the mechanisms and clinical relevance of transaminase changes after mipomersen administration. (Dose-Escalating Safety Study in Subjects on Stable Statin Therapy; NCT00231569).
Akdim
Fatima
F
Department of Vascular Medicine, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
Stroes
Erik S G
ES
Sijbrands
Eric J G
EJ
Tribble
Diane L
DL
Trip
Mieke D
MD
Jukema
J Wouter
JW
Flaim
Joann D
JD
Su
John
J
Yu
Rosie
R
Baker
Brenda F
BF
Wedel
Mark K
MK
Kastelein
John J P
JJ
D001055:Apolipoproteins B / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood* / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use*; D006937:Hypercholesterolemia / Q000097:blood / Q000188:drug therapy*; D007279:Injections, Subcutaneous; D008297:Male; D008875:Middle Aged; D009841:Oligonucleotides / Q000008:administration & dosage / Q000627:therapeutic use*; D015995:Prevalence; D012189:Retrospective Studies; D016896:Treatment Outcome
D001055:Apolipoproteins B; D008078:Cholesterol, LDL; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D009841:Oligonucleotides; C524142:mipomersen