Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

Down-regulation of cyclic-nucleotide phosphodiesterase 3B in 3T3-L1 adipocytes induced by tumour necrosis factor alpha and cAMP.

We have used murine 3T3-L1 cells, which differentiate in culture and acquire morphological and biochemical features of mature adipocytes, as a model for studying the expression of cyclic-nucleotide phosphodiesterase (PDE) 3B activity, protein and mRNA during differentiation and during long-term treatment of the cells with tumour necrosis factor alpha (TNF-alpha), a cytokine associated with insulin resistance, and a cAMP analogue, N(6),2'-O-dibutyryl cAMP (dbcAMP). PDE3B activity, protein and mRNA could be detected 4 days after the initiation of differentiation of 3T3-L1 preadipocytes. Treatment of 3T3-L1 adipocytes with 10 ng/ml TNF-alpha for 24 h produced a maximal (50%) decrease in PDE3B activity, protein and mRNA, which was well correlated with both activation of protein kinase A (PKA) and stimulation of lipolysis, presumably reflecting an increase in intracellular cAMP concentration. To investigate the effect of cAMP on PDE3B we treated 3T3-L1 adipocytes with dbcAMP. After 4 h with 0.5 mM dbcAMP, PDE3B activity was decreased by 80%, which was also correlated with a decrease in PDE3B protein and mRNA. This effect was abolished in the presence of N-[2-(bromocinnamylamino)ethyl]-5-isoquinolinesulphonamide] (H-89), a specific PKA inhibitor. We conclude that the lipolytic effect of TNF-alpha involves the down-regulation of PDE3B, which is associated with increased activation of PKA, presumably owing to increased levels of cAMP. In addition, the PKA activation induced by dbcAMP resulted in the down-regulation of PDE3B. These results, which suggest that PDE3B is a novel target for long-term regulation by TNF-alpha and cAMP, could contribute to the understanding of the mechanisms of insulin resistance