Sinai Center for Thrombosis Research Baltimore, Maryland, U.S.A. We Should Tailor Antiplatelet Therapy Based on Platelet Function Testing and Genotyping Paul A. Gurbel, M.D. Sinai Center for Thrombosis Research Baltimore, Maryland, U.S.A.

Paul A. Gurbel, MD Consulting: Eli Lilly and Company, Pozen, Inc., Accumetrics, Inc., Daiichi Sankyo, Novartis AG, Bayer Corporation, Sanofi-Aventis, Boehringer Ingelheim Vetmedica GmbH, Merck and Company, Inc. and Medtronic, Inc. Grant Support: Daiichi Sankyo, Eli Lilly and Company, CSL, Haemoscope Corporation, Harvard Clinical Research Institute, Duke Clinical Research Institute, Pozen, Inc., Accumetrics, Inc., Helena Laboratories, Verum Diagnostica GmbH and Portola Pharmaceuticals, Inc.

Post-PCI/MI Thrombotic Events- A “Plateletcentric” Problem!!!! PCI/ACS Platelet Adhesion /Activation Thrombin ADP TxA2 Sustained GPIIb/IIIa Activation P2Y12 Blockers x Platelet Aggregation Hypercoagulability Inflammation Ischemic Events/Stent Thrombosis Gurbel PA et al. Circulation. 2012;125:1276-87 4

Platelet Function Testing

How can we rationalize giving this drug blindly Aggregation On Aspirin and Aspirin + Clopidogrel Clopidogrel is a highly unpredictable and overall weak antiplatelet agent. Aggregation in 42% of pts on C+A is in the same range as 50% of pts treated with A alone! How can we rationalize giving this drug blindly to patients with high risk CVD? 100 42% 50% 8hr post- 600mg Clopidogrel Aspirin 75-100mg qd 80 60 Cumulative Frequency (%) 40 20 20 40 60 80 100 120 20uM ADP-Induced Aggregation Gurbel PA and Tantry US. Circulation. 2012 ;125: 1276-87. 6

Relation of On-Treatment Platelet Reactivity to ADP to Post-PCI Ischemic Events: Early Evidence Gurbel PA et al. J Am Coll Cardiol. 2005; 46:1820-6 ~Immunity from Ischemic Event Occurrence 46% 7

VerifyNow P2Y12 Patient Based Meta-Analysis : 2 Year Outcomes 6 studies, n=3,059 2 Yr MACE by PRU Quartile 2 Yr Stent Thrombosis by PRU Quartile Very low ST rate ~ immunity ~3x risk between Q1 and Q4 ~8x risk between Q1 and Q4 Brar SS, et al. J Am Coll Cardiol. 2011;58:1945–54

Personalization of Antiplatelet Therapy: Relation of HPR to Outcomes We now have data in tens of thousands of patients: High Platelet Reactivity to ADP (HPR) is a major risk factor for post-PCI thrombotic event occurrence. Gurbel PA and Tantry US. Circulation. 2012 ;125: 1276-87. 9

ADAPT-DES Registry: 30 Day ST by HPR 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Days 5 10 15 20 25 30 0.81% 0.21% P2Y12 PRU > 208 (n=3607) P2Y12 PRU ≤ 208 (n=4834) P <0.001 HR [95% CI]= 3.89 [1.90, 7.98] Definite/Probable ST (%) ~ 4X Increase absolute difference = 0.6% N=8349 Multivariable (Cox PHR) model: 50% of 30 d definite or probable stent thrombosis solely attributable to HPR! Multivariable Propensity Score Adjusted Risk of VerifyNow PRU >208 1-year Adverse Events Event Adj HR [95%CI] P value ST, def/prob 2.49 [1.43, 4.31] 0.001 - Definite 3.05 [1.62, 5.75] 0.0006 MI 1.42 [1.09, 1.86] 0.01 Major bleeding 0.73 [0.61, 0.89] 0.002 Death, all-cause 1.20 [0.85, 1.70] 0.30 Stone G, et al. Presented at TCT 2011 and 2012

Have Failed to Show Benefit of Tailoring - Low risk patients (all trials) - Remedy for HPR (high dose clopidogrel) suboptimal (GRAVITAS, ARCTIC) - Low post-D/C event rates (all trials): - Incomplete protocol following (ARCTIC) - difficult to perform positive randomized trial with adequate n Why Aren't We Tailoring? GRAVITAS, TRIGGER-PCI and ARCTIC 3 Major Prospective Trials of Personalized Antiplatelet Therapy- in the PCI Patient Have Failed to Show Benefit of Tailoring

Genetic Testing

A genetic locus unequivocally associated with clopidogrel response variability Shuldiner AR and Gurbel PA, et al. JAMA. 2009;302:849-57 Genome Wide Association Study ~ 500,000 SNP’s 13 SNP’s cluster (1.5 mb on 10q24)

CYP2C19 LoF = ~ 30% Americans & ~ 2% are homozygotes 2C19 LoF Carriage Associated With Post-PCI Thrombotic Outcomes Carriers Non-carriers JAMA 2010;304:1821-1830 Hulot:Meta-analysis TRITON TIMI-38 Primary Outcomes (%) J Am Coll Cardiol. 2010;56:134-43 9.3 7.8 10 12.6 8.4 12.1 8 8.5 9.8 2 4 6 12 14 Mega:Meta-Analysis 1 LoF 2 LoF None 1 LoF 2 LoF None 1 LoF 2 LoF None Clopidogrel Prasugrel n=11,959 2.9 0.9 4.9 n=5,694 Stent Thrombosis n=9,685 2.2 0.94 5.7 n=5,787 n=1,477 n=1,466 Mega Circ 2009;119:2553-60;NEJM 2009;360:354-62 1.3 1.5 0.9 1.6 1.8 3.3 4.7 2.8 4.0 CYP2C19 LoF = ~ 30% Americans & ~ 2% are homozygotes Platelet reactivity in the clopidogrel-treated homozygotes is very high - a subject of FDA “boxed warning” 14

The RAPID Program: Spartan RX CYP2C19 System Buccal Swab/Real Time PCR 60 minutes to identify: CYP2C19*2 carrier status Heterozygous vs. Homozygous Patients undergoing PCI for non ST-ACS or stable CAD N=200 Rapid Genotyping N=102 Platelet Function Testing at 1 week CYP2C19*2 Carriers N=23 Non-Carriers N=74 Prasugrel 10 mg OD Clopidogrel 75 mg OD Standard Therapy N=98 Point-of-Care Genotyping Roberts JD et al. Lancet. 2012;379:1705-11

RAPID GENE Trial: Results Rapid Genotyping (N=91) Standard Therapy (N=96) Carriers of CYP2C19*2 allele no.(%) 23 (25.3) 23 (24.0) Heterozygous CYP2C19*2 no.(%) 19 (20.9) 20 (20.8) Homozygous CYP2C19*2 no.(%) 4 (4.4) 3 (3.1) Performance Characteristics of Rapid Testing vs. Direct DNA Sequencing Sensitivity – 100% Specificity – 99.4% Prevalence of HPR (%) p = 0.01 31 10 20 30 Rapid Genotyping Standard Therapy 40 15 (PRU>208) Roberts JD et al. Lancet. 2012;379:1705-11

Cost Analysis Clopidogrel is pharmacodynamically effective in ~ 65% Unselected use of new agents : more bleeding more cost Selective use of generic clopidogrel : more economical No convincing evidence that prasugrel or ticagrelor confer more benefit in clopidogrel responders. 2 4 6 8 10 12 14 TRITON TIMI-38 PLATO 12.1 8.5 8.0 9.8 11.2 8.6 10.0 8.8 LoF Carriers 30% LoF Non-carriers LoF Carriers 30% Primary Efficacy Outcome (%0 Clopidogrel Prasugrel Ticagrelor Gurbel PA et al. Expert Rev Cardiovasc Ther. 2004;2:535-45 17

Consensus/Guidelines/Alerts/FDA Statements Addressing Platelet Function Testing IIb III-No Benefit: Routine Analysis

Why We Should Tailor Antiplatelet Therapy Based on Platelet Function Testing and Genotyping Because specific genotypes and HPR are associated with stent thrombosis and death during clopidogrel therapy. 2) There are no proven reasons why antiplatelet agents reduce thrombosis other than inhibiting P2Y12 receptor. 3) Because ARCTIC and GRAVITAS have limitations and shouldn’t be used to disprove the utility of personalization 4) How can we rationalize giving a placebo in one third of patient population to prevent the most catastrophic event? 5) How can we rationalize giving an expensive drug associated with more bleeding to all patients when a 33 cents /day drug works in two third of patients population?