Effects of CETP inhibition on triglyceride-rich lipoprotein composition and apoB-48 metabolism

J Lipid Res. 2012 Jun;53(6):1190-9. doi: 10.1194/jlr.M019570. Epub 2012 Apr 2.


Cholesteryl ester transfer protein (CETP) facilitates the transfer of HDL cholesteryl ester to triglyceride-rich lipoproteins (TRL). This study aimed to determine the effects of CETP inhibition with torcetrapib on TRL composition and apoB-48 metabolism. Study subjects with low HDL cholesterol (<40 mg/dl), either untreated (n = 9) or receiving atorvastatin 20 mg daily (n = 9), received placebo for 4 weeks, followed by torcetrapib 120 mg once daily for the next 4 weeks. A subset of the subjects not treated with atorvastatin participated in a third phase (n = 6), in which they received torcetrapib 120 mg twice daily for an additional 4 weeks. At the end of each phase, all subjects received a primed-constant infusion of [5,5,5-(2)H(3)]L-leucine, while in the constantly fed state, to determine the kinetics of TRL apoB-48 and TRL composition. Relative to placebo, torcetrapib markedly reduced TRL CE levels in all groups (≥-69%; P < 0.005). ApoB-48 pool size (PS) and production rate (PR) decreased in the nonatorvastatin once daily (PS: -49%, P = 0.007; PR: -49%, P = 0.005) and twice daily (PS: -30%, P = 0.01; PR: -27%, P = 0.13) cohorts. In the atorvastatin cohort, apoB-48 PS and PR, which were already lowered by atorvastatin, did not change with torcetrapib. Our findings indicate that CETP inhibition reduced plasma apoB-48 concentrations by reducing apoB-48 production but did not have this effect in subjects already treated with atorvastatin.

Publication types

  • Controlled Clinical Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Apolipoprotein B-48 / blood
  • Apolipoprotein B-48 / metabolism*
  • Cholesterol Ester Transfer Proteins / antagonists & inhibitors*
  • Female
  • Humans
  • Kinetics
  • Lipoproteins / blood
  • Lipoproteins / chemistry*
  • Lipoproteins / metabolism*
  • Male
  • Middle Aged
  • Quinolines / pharmacology
  • Triglycerides*


  • Apolipoprotein B-48
  • Cholesterol Ester Transfer Proteins
  • Lipoproteins
  • Quinolines
  • Triglycerides
  • torcetrapib