Effect of apolipoprotein-B synthesis inhibition on liver triglyceride content in patients with familial hypercholesterolemia

To investigate the impact of mipomersen, an apolipoprotein B-100 (apoB) synthesis inhibitor, on intrahepatic triglyceride content (IHTG content), we conducted a randomized, double-blind, placebo-controlled study in 21 patients with familial hypercholesterolemia (FH). Subjects received a weekly subcutaneous dose of 200 mg mipomersen or placebo for 13 weeks while continuing conventional lipid lowering therapy. The primary endpoint was change in IHTG content from week 0 to week 15 as measured by localized proton magnetic resonance spectroscopy (1H-MRS). Thirteen weeks of mipomersen administration reduced LDL-cholesterol by 22.0 (17.8) % and apoB by 19.9 (17.4) % (both P < 0.01). One of 10 patients (10%) in the mipom-ersen- treated group developed mild hepatic steatosis at week 15, which was reversible following mipomersen discontinuation. For the group, there was a trend toward an increase in IHTG content [placebo; baseline: 1.2% and week 15: 1.1%; change -0.1 (0.9). Mipomersen; baseline: 1.2% and week 15: 2.1%; change 0.8 (1.7) (P = 0.0513)]. Mipomersen administration for 13 weeks to subjects with FH is associated with a trend toward an increase in IHTG content. Future studies evaluating the effects of long-term use of mipomersen reaching more profound reductions in apoB are required prior to broader use of this compound. Visser, M. E., F. Akdim, D. L. Tribble, A.. J. Nederveen, T. J. Kwoh, J. J. P. Kastelein, M. D. Trip, and E. S. G. Stroes. Effect of apolipoprotein-B synthesis inhibition on liver triglyceride content in patients with familial hypercholesterolemia. J. Lipid Res. 2010. 51: 1057-1062.