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Residual risk and HDL-cholesterol: What are the current perspectives?. Prof. Erik Stroes Academic Medical Centre Amsterdam, The Netherlands. -34 †. -31 ‡. -36 †. -27 †. Is There a Therapeutic Need Beyond LDL Lowering ?. WOSCOPS 2. 4S 3. ASCOT-LLA 4. CARDS 5 *. HPS 1. 0.
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Residual risk and HDL-cholesterol:What are the current perspectives? Prof. Erik Stroes Academic Medical Centre Amsterdam, The Netherlands
-34† -31‡ -36† -27† Is There a Therapeutic Need Beyond LDL Lowering ? WOSCOPS2 4S3 ASCOT-LLA4 CARDS5* HPS1 0 Reduction in major coronary events vs placebo (%) -20 -36† -37‡ -40 Percent Potential for further risk reduction -60 -80 1. Heart Protection Study Collaborative Group. Lancet. 2002;360:7-22; 2. Shepherd J et al. N Engl J Med. 1995;333:1301-1307; 3. Scandinavian Simvastatin Survival Study Group. Lancet. 1994;344:1383-1389; 4. Sever PS et al. Lancet. 2003;361:1149-1158; 5. Colhoun HM et al. Lancet. 2004;364:685-696.
Selecting ‘promising’ candidates Based on Epidemiology 3.0 N = 302,430 2.0 Hazard Ratio 1.0 30 40 50 60 70 80 HDL-C (mg/dL) The Emerging Risk Factors Collaboration. JAMA 2009;302:1993-2000
HDL(-c) is ‘a mixed bag’Cholesterol concentration versus ‘particle’ Shape Electrophoretic mobility Pre-β-2 Pre-β-3 Discoidal HDL Spherical HDL Density and size α1 α2 HDL3b HDL2b HDL2a HDL3a HDL3c α3 HDL2 HDL3 1.063 Density (g/mL) 1.21 α4 Diameter (nm) 10.6 7.6 Apolipoprotein composition Pre-β-1 Pre-β migration α migration Origin LpA-I LpA-I:A-II Camont L, et al. Trends Mol Med. 2011;17(10):594-603.
Peripheral cell FC, PL ABCA1 ABCG1 Intestine LCAT FC Pre-β-HDL HDL3 CE VLDL VLDL-R IDL LDL CE TG LCAT Lipid-free A-I CETP CE PLTP HL EL FC HDL2 TG CE A-I HDL-R SR-BI LDL-R Hepatocyte FC, CE FC, CE Many ways to increase HDL-c Maturation Production Remodeling Clearance Kontush A, Nature CPCM 2008
OutlineHDL-c and CV-protection Protective mechanisms Epidemiology versus Genetics Lessons learnt from HDL-c increasing trials The future for interventions targeting HDL-c
Quantity versus Quality Other effects ‘carrier platform’ Reverse cholesterol transport ‘cholesterol carrier’ QUANTITY HDL-C / Apo AI QUALITY Particle structure Functionality Chapman MJ. PharmacolRev. 2006.
HDL Increases Cholesterol Flux:Whole-body and ‘Vascular’ 35% peakIncrease AfterInfusion Before Infusion Bile Acids 400 Neutral Sterols HDL-C (mg/dl) 41±7 300 Intestinal Excretion mg/day 200 100 0.0 SG GG LM IN Eriksson, Circ 1999 Shaw, CircRes 2008
Static versus Dynamic 13C-cholesterol TracerDilution Flux “Control” “Carrier of APOA1 De Goma, Rader, JACC 2008
Endothelial Function (Endothelial cell NO production) Anti-thrombotic effects Anti-oxidant effects (Endothelial cell superoxide production) Anti-inflammatory effects (Endothelial cell inflammatory activation) REVERSE CHOLESTEROL TRANSPORT HDL protectionbeyond RCT HDL increase Vascularprotection
HDL Improves Endothelial Functionin ABC-A1 Heterozygotes Restoration of Endothelial Function Bisoendial RJ, Stroes El. Circulation 2003 Nieuwdorp, Stroes E, Diabetologia 2008
HDL: carrierorcarrier-‘platform‘ ? Phospholipids Triglycerids Esterified cholesterol ApoA1 PON-1 Free cholesterol Cholesterol Ester • 70 different proteins (ApoA1, PON-1,ApoA2,ApoCIII,ApoE,ApoH, ….) > 1000 different lipids (Phospholipidspecies, Cholesterol Ester, Trigylcerides, …)
Summary Iprotective mechanisms • HDL is both • ‘cholesterol acceptor’ • ‘carrier’ of enzymes/proteins • HDL can lose its ‘protective’ effects • ‘Best test’ for HDL-quality and‘relevance’ of HDL-quality for CV-risk Unknown
Epidemiology versus GeneticsLDL vs HDL We confirm that genetically raised plasma HDL cholesterol is not associated with risk of myocardial infarction. A genetic score consisting of these 14 variants was not associated with risk of myocardial infarction. These results show that some ways of raising HDL cholesterol might not reduce risk of myocardial infarction in human beings. OR per SD increase in plasma lipid Observational epidemiology* OR per SD increase in plasma lipid Genetic score** LDL-c HDL-c 1.54(1.45-1.63) 0.62(0.58-0.66) 2.13 (1.69-2.69) p=2x10-10 0.93(0.68-1.26), p=0.63 • Observational epidemiology estimates derived from more than 25 000 individuals from prospective cohort studies as shown in the appendix p 22. • ** LDL genetic score consisting of 13 single necleotide polymorphisms (SNPs) as shown in the appendix p 27; • HDL genetic score consisting of 14 SNPs as shown in the appendix p 28. Voight, Lancet 2012
Summary IIEpidemiology vs Genetics • Overall, genetic HDL-c changes not related to risk: • 6 HDL-related variants do associate with risk • Extreme genetic HDL-phenotypes associate with risk • Whereas the impact of HDLc on risk is evident,the effect of ‘raising’ HDLc might not invariably reduce risk of MI
‘Negative’ HDLc trials Revisited • AIM-HIGH: Niacin • ILLUMINATE: Torcetrapib • dal-OUTCOMES: Dalcetrapib
AIM HIGH:AtherothrombosisIntervention in Metabolic Syndrome With Low HDL/High Triglycerides and Impact on Global Health Outcomes Simvastatin40 mg + ER niacin 2 g 3300 patients Simvastatin40 mg • Men and women • Aged 45 years • Established vascular disease and atherogenicdyslipidemia (low HDL-C and high triglycerides) 4-year follow-up • Primary End Point • Composite of CHD death, nonfatal MI, ischemic stroke, or hospitalization for high-risk ACS with objective evidence of ischemia • Key Secondary End Points • Composite of CHD death, nonfatal MI, or ischemic stroke clinicaltrials.gov/ct/show/NCT00120289
AIM-HIGH Powered to detect 25% reduction in CV events LDL-c in placebo group ‘titrated’ to <1.8mmol/l(adding ezetimibe / increasing statin dose) On-treatment difference in HDL-C 4 mg/dL (~ 4% event reduction) Overall conclusion (Nissen et al) ‘no consequences for clinical practice’ Boden et al. N Eng J Med 2011; 356:2255
ILLUMINATE: Primary Endpoint: Time to First MCVE*: Kaplan-Meier Plot Hazard Ratio 1.25 100 P=0.001 Event Free (%) 98 96 94 Atorvastatin (A) events = 373 Torcetrapib/Atorvastatin (T/A) events = 464 92 90 0 90 180 270 360 450 540 630 720 810 Days from Randomization *Major cardiovascular event: CHD death, non-fatal MI, stroke or hospitalization for unstable angina Barter et al, NEJM 2007;357:2109
Inhibiting CETP is wrong: wrong ‘pathway’ to increase HDL-c ? Inhibition of CETP generates ‘dysfunctional’ HDL ? Torcetrapib is wrong off-target effects unrelated to CETP Reasons for adverse outcome with Torcetrapib
- increases aldosterone / cortisol increases blood pressure - reduces eNOS, - increases ET-1 induces endothelial dysfunction Other CETP inhibitors do not have these off-target effects Off-target effects of Torcetrapib Forrest et al. Br J Pharmacol. 2008;154:1465-1473). Hu et al. Endocrinology 2009;150:2211-2219. Capponi et al. Circulation 2008;118:S:452. Connelly et al. J Cardiovasc Pharmacol 2010; 55:459. Simic et al. Eur Heart J. 2012 (in press)
Dal-OUTCOMES Trial Dalcetrapib 600 mg 15,600 patients 4-12 weeks after an index ACS event Statin therapy to optimal LDL-C level Placebo 2.5-year follow-up Primary End Point CHD death, non-fatal MI, atherothrombotic stroke, unstable angina requiring hospitalization or resuscitated cardiac arrest Schwartz et al. Am Heart J. 2009;158:896.
Why did dalcetrapib fail to reduce CV events? Explanations ? • weak inhibitor, hence no impact on CV events • CETP inhibition pro-atherogenic • HDL-C increase no valid target
Other CETP-Inhibitors ? Changes of lipid-parameters in % Torcetrapib* 60 mg/d Pfizer* Dalcetrapib* 600 mg/d Roche Anacetrapib100 mg/d MSD Evacetrapib 500 mg/d Lilly Total chol LDL-c Triglycerides Apo B HDL-c ApoA1 Lp(a) • + 4 • - 24 • - 9 • - 12 • + 61 • + 25 + 8 - 2 - 3 + 4 + 31 + 11 -7 • + 16 • - 40 • - 7 • - 21 • + 138 • + 45 • - 38 • + 11 • - 40 • - 20 • - 26 • + 132 • + 50 HaltedToxicity HaltedFutility Ongoing Reveal * Clinical development program of Torcetrapib & Dalcetrapib stopped Cannon C, JAMA 2011;306:2153
Future • 30,000 patients with occlusive arterial disease in North America, Europe and Asia • Background LDL-lowering with atorvastatin • Randomized to anacetrapib 100 mg vs. placebo • Primary outcome: Coronary death, myocardial infarction or coronary revascularization www.revealtrial.org.
Summary IIILessons HDLc-increasing trials • Trials to date haven’t solved the question whether HDL should be a therapeutic target • Lessons we did learn: • Power adequately with realistic ‘benefit’AIM-HIGH failed • Watch out for adverse effects prior to endpoint trialTorcetrapib failed • Test the compound, not the mechanismAIM-HIGH
Therapies on the Horizon Reconstituted apoAI/HDL ; HDL delipidation pre-β HDL ApoAI upregulation CETP Inhibitors HDL hyperTGemia Omega-3 FAs ApoAIupregulation apoCIII ApoAI mimetics PPAR agonists ABCA1 induction / LXR agonists apoAII apoE sPLA2 HL EL LCAT SR-B1 Niacin analogues
Targeting cholesterol ‘flux’ by increasing ApoA-I rHDL CER001 RVX-208 Target HDL Phospholipids ABC-A1 Cholesterol ApoA-I Protein ApoA-I mRNA Cytoplasm ApoA-I Gene Nucleus Hepatocyte 7
Indications for ‘apo-AI/HDL infusables’ Re-events after ACS cholesterol Days ‘Therapeutic gap’after ACS ‘Lipid-rich’ coredepletion Anti-inflammatory Targeted delivery
Take Home: • In CVRM: • measure HDLc for risk-scoring (1C) • Treat LDLc more vigorous in case of low HDLc (1C) • If HDLc is low in high risk: • consider adding nicotinic acid (2A) • Validity of co-targeting HDL-c will be revealed < 3-4 years (HPS2/Reveal) • Research foci in HDLc: • Concentration vs Quality / Flux • ‘Where’ to intervene (production/remodeling/clearance) • How to measure succes (PET-CT / MRI)