Dalcetrapib
The first human trial of JTT-705 finds 900 mg raises HDL cholesterol by 34 percent while cutting CETP activity by 37 percent (Circulation 2002)
Original title: Efficacy and safety of a novel cholesteryl ester transfer protein inhibitor, JTT-705, in humans: a randomized phase II dose-response study
After earlier studies showed the CETP inhibitor JTT-705 raised HDL cholesterol and slowed atherosclerosis progression in cholesterol-fed rabbits, this randomized, double-blind, placebo-controlled trial reported the first results of JTT-705 in humans. In 198 healthy subjects with mild hyperlipidemia, daily treatment with 300, 600, or 900 mg JTT-705 for 4 weeks was evaluated for efficacy and safety. The 900 mg dose produced a 37% decrease in CETP activity (p < 0.0001), a 34% increase in HDL cholesterol (p < 0.0001), and a 7% decrease in LDL cholesterol (p = 0.017), with rises in HDL2, HDL3, and apolipoprotein A-I, while triglycerides, phospholipid transfer protein, and lecithin-cholesterol acyltransferase were unaffected. JTT-705 showed no toxicity on physical examination or routine laboratory tests, with only minor gastrointestinal side effects (p = 0.06), establishing CETP inhibition as an effective way to raise HDL cholesterol in humans.
Original abstract
Background: Cholesteryl ester transfer protein (CETP) mediates the transfer of neutral lipids between lipoproteins. High plasma levels of CETP are correlated with low HDL cholesterol levels, a strong risk factor for coronary artery disease. In earlier studies, JTT-705, a novel CETP inhibitor, was shown to increase plasma HDL cholesterol and to inhibit the progression of atherosclerosis in cholesterol-fed rabbits. This study describes the first results using this CETP inhibitor in humans.
Methods And Results: In a randomized, double-blind, and placebo-controlled trial, we evaluated the efficacy and safety of daily treatment with 300, 600, and 900 mg JTT-705 in 198 healthy subjects with mild hyperlipidemia. Treatment with 900 mg JTT-705 for 4 weeks led to a 37% decrease in CETP activity (P<0.0001), a 34% increase in HDL cholesterol (P<0.0001), and a 7% decrease in LDL cholesterol (P=0.017), whereas levels of triglycerides, phospholipid transfer protein, and lecithin-cholesterol acyltransferase were unaffected. In line with the increase of total HDL, a rise of HDL2, HDL3, and apolipoprotein A-I was also noted. JTT-705 showed no toxicity with regard to physical examination and routine laboratory tests.
Conclusions: We show that the use of the CETP inhibitor JTT-705 in humans is an effective means to raise HDL cholesterol levels with minor gastrointestinal side effects (P=0.06). Although these results hold promise, further studies are needed to investigate whether the observed increase in HDL cholesterol translates into a concomitant reduction in coronary artery disease risk.
Summary written by cetpinhibition.org from the published abstract; figures as published. Page updated 18 August 2026. Methods.