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Biomarkers and Clinical Care Lessons Learned from Case Studies: The Challenges and the Promise of Predictive Biomarker

Disclosure. I am an employee of Bristol-Myers Squibb Company and I own stock in Bristol-Myers Squibb and in other pharmaceutical companiesBristol-Myers Squibb manufactures and sells Plavix ? and Erbitux? Any reference to information not contained within drug labeling is unintentional.. Personal

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Biomarkers and Clinical Care Lessons Learned from Case Studies: The Challenges and the Promise of Predictive Biomarker

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    1. Biomarkers and Clinical Care Lessons Learned from Case Studies: The Challenges and the Promise of Predictive Biomarkers Steven D. Averbuch, MD Vice President, Oncology Transition Strategy & Development and Head, Pharmacodiagnostics Global Clinical Research Bristol-Myers Squibb Add Merck as a partner; partner companies (not development partners)Add Merck as a partner; partner companies (not development partners)

    2. Disclosure I am an employee of Bristol-Myers Squibb Company and I own stock in Bristol-Myers Squibb and in other pharmaceutical companies Bristol-Myers Squibb manufactures and sells Plavix ® and Erbitux® Any reference to information not contained within drug labeling is unintentional.

    3. Personalized Medicine A shift from conventional disease oriented approach to biologically defined personalized approach leads to improved performance of drugs Through the research and discoveries we are making eventually we will start to deliver tests that will allow physicians to selectively treat cancer patients with the best drugs. In this room we are using a very sophisticated machine to look at differences in genes so that we can identify those genes that correlate to response. We are able to examine about 8,000 genotypes/day or roughly 2million/year. Our Company has also taken a lead position in the emerging field of pharmacogenomics and personalized medicines. We believe pharmocogenomics in the clinic offer several advantages to drug development, to improved medicines for patients. Today it is becoming commonplace to examine a single gene on a tumor biopsy to select treatment. We believe that in the future, expanding that approach to scan large sets of genes will improve our ability to find the right drug for the right patient. Through our internal genomics effort, as well as through our alliances with Millennium, the Whitehead Genomics Center, Impath, Exelixis and major clinical centers, we are integrating this approach extensively into our oncology pipeline. Through the research and discoveries we are making eventually we will start to deliver tests that will allow physicians to selectively treat cancer patients with the best drugs. In this room we are using a very sophisticated machine to look at differences in genes so that we can identify those genes that correlate to response. We are able to examine about 8,000 genotypes/day or roughly 2million/year. Our Company has also taken a lead position in the emerging field of pharmacogenomics and personalized medicines. We believe pharmocogenomics in the clinic offer several advantages to drug development, to improved medicines for patients. Today it is becoming commonplace to examine a single gene on a tumor biopsy to select treatment. We believe that in the future, expanding that approach to scan large sets of genes will improve our ability to find the right drug for the right patient. Through our internal genomics effort, as well as through our alliances with Millennium, the Whitehead Genomics Center, Impath, Exelixis and major clinical centers, we are integrating this approach extensively into our oncology pipeline.

    4. Pharmacodiagnostics The Hype Surrounding Personalized Medicine Needs to be Balanced Against Many Challenges Research & Development Regulatory Commercial / Economics

    5. Pharmacodiagnostics The Hype Surrounding Personalized Medicine Needs to be Balanced Against Many Challenges Research & Development Establishing molecular mechanism and biomarkers Selecting and optimizing diagnostic platforms Clinical specimen acquisition Clinical validation Potential decrease in therapeutic development productivity Relevant biomarker science is often out of step with drug development timing

    6. Co-Development: Drug and PDx Ideal Paradigm You might ask why, if a PDx is tied to the development of an asset, we need a separate group of resources outside of the EDT/FDT or LCMT focusing on the companion diagnostic? This slide depicts the ‘ideal’ process by which a PDx is developed and approved. In reality, we have a steep learning curve associated with each of these steps /arrows. (Cite examples) Given that the incorporation of PDx adds to the complexity of drug R&D, it seemed wise to have a group of resources who could become well-versed in the issues, thereby releasing teams from some of the burden of educating themselves and understanding the best path forward. The PDxT also helps assure organizational learning from our efforts over time and the collection of experience (rather than repetition of mistakes from teams working independently from one another)You might ask why, if a PDx is tied to the development of an asset, we need a separate group of resources outside of the EDT/FDT or LCMT focusing on the companion diagnostic? This slide depicts the ‘ideal’ process by which a PDx is developed and approved. In reality, we have a steep learning curve associated with each of these steps /arrows. (Cite examples) Given that the incorporation of PDx adds to the complexity of drug R&D, it seemed wise to have a group of resources who could become well-versed in the issues, thereby releasing teams from some of the burden of educating themselves and understanding the best path forward. The PDxT also helps assure organizational learning from our efforts over time and the collection of experience (rather than repetition of mistakes from teams working independently from one another)

    7. Only In Few Cases Have Subgroups Been Defined in Advance With Formal Analysis Imatinib and Kit + GIST (prospective, preapproval) Dasatinib and PH + ALL (prospective, preapproval) Maraviroc and CCR5 + (tropic) HIV-1 (prospective, preapproval) Tetrabenazine and 2D6 dosing (prospective, preapproval) Trastuzumab and HER2+ Br Ca (“prospective”, preapproval)

    8. How Pharmacodiagnostics can Streamline Clinical Development and Increase Value

    9. Trial Design to Establish Clinical Utility: An Ideal Situation A definitive clinical study for a drug used in conjunction with a predictive biomarker allows for assessment of a drug’s safety and efficacy and for verification of the clinical utility of the biomarker in guiding the drug’s use including appropriate patient selection, and consequently enables labeling

    10. Only In Few Cases Have Subgroups Been Defined in Advance With Formal Analysis Imatinib and Kit + GIST (prospective, preapproval) Dasatinib and PH + ALL (prospective, preapproval) Maraviroc and CCR5 + (tropic) HIV-1 (prospective, preapproval) Tetrabenazine and 2D6 dosing (prospective, preapproval) Trastuzumab and HER2+ Br Ca (“prospective”, preapproval) Nilotinib and UGT hyperbilirubin (retrospective, preapproval) Abacavir and HLAB*5701 HAS (prospective, post-approval) Clopidegrel and 2C19 “resistance” (prospective, post-approval) Cetuximab / Panitumamab and KRAS (retrospective, post-approval) Carbamazepine and HLAB*1502 SJS (retrospective, post-approval) Warfarin and 2C9/VKORC1 dosing (retrospective, post-approval)

    11. Co-Development: Drug and PDx Ideal Paradigm You might ask why, if a PDx is tied to the development of an asset, we need a separate group of resources outside of the EDT/FDT or LCMT focusing on the companion diagnostic? This slide depicts the ‘ideal’ process by which a PDx is developed and approved. In reality, we have a steep learning curve associated with each of these steps /arrows. (Cite examples) Given that the incorporation of PDx adds to the complexity of drug R&D, it seemed wise to have a group of resources who could become well-versed in the issues, thereby releasing teams from some of the burden of educating themselves and understanding the best path forward. The PDxT also helps assure organizational learning from our efforts over time and the collection of experience (rather than repetition of mistakes from teams working independently from one another)You might ask why, if a PDx is tied to the development of an asset, we need a separate group of resources outside of the EDT/FDT or LCMT focusing on the companion diagnostic? This slide depicts the ‘ideal’ process by which a PDx is developed and approved. In reality, we have a steep learning curve associated with each of these steps /arrows. (Cite examples) Given that the incorporation of PDx adds to the complexity of drug R&D, it seemed wise to have a group of resources who could become well-versed in the issues, thereby releasing teams from some of the burden of educating themselves and understanding the best path forward. The PDxT also helps assure organizational learning from our efforts over time and the collection of experience (rather than repetition of mistakes from teams working independently from one another)

    12. Pharmacodiagnostics The Hype Surrounding Personalized Medicine Needs to be Balanced Against Many Challenges Research & Development Establishing molecular mechanism and biomarkers Selecting and optimizing diagnostic platforms Clinical specimen acquisition Clinical validation Potential decrease in therapeutic development productivity Relevant biomarker science is often out of step with drug development timing Regulatory Integrated regulatory requirements (e.g., evidentiary standard) are not established and currently inconsistent Regulatory and reimbursement standards within and across major markets (US, EU, and JP) are not harmonized

    14. Regulatory Considerations for Drug/Diagnostic Development Laboratory developed test (LDT) - created in a single lab for use at that specific lab General Purpose Reagents (GPRs) are chemical reagents and Analyte-Specific Reagents (ASRs) are building blocks or active ingredients (i.e. antibodies, receptor proteins) used in a Laboratory Developed Test (LDT) No requirement for premarket review by FDA Subject to Clinical Laboratory Improvement Amendments (CLIA) with oversight by CMS Analytical performance Quality system No clinical validation (not prohibited but not required by CLIA) No threshold between research and clinical use ASRs are required to be performed in CLIA “high-complexity” testing labs and are subject to registration and listing, GMP, adverse result reporting, and transparency in labeling Diagnostic test “kits” - reagents, instruments and systems that are developed in the form of a kit and sold by a Device manufacturers Regulated by FDA – subject to premarket review Per CFR: IVDs are reagents, instruments, and systems intended for use: in diagnosis of disease or other conditions, including the determination of the state of health, in order to cure, mitigate gate or treat, or prevent disease and are intended for use in the collection, preparation, and examination of specimens taken from the human body Laboratory developed test (LDT) - created in a single lab for use at that specific lab General Purpose Reagents (GPRs) are chemical reagents and Analyte-Specific Reagents (ASRs) are building blocks or active ingredients (i.e. antibodies, receptor proteins) used in a Laboratory Developed Test (LDT) No requirement for premarket review by FDA Subject to Clinical Laboratory Improvement Amendments (CLIA) with oversight by CMS Analytical performance Quality system No clinical validation (not prohibited but not required by CLIA) No threshold between research and clinical use ASRs are required to be performed in CLIA “high-complexity” testing labs and are subject to registration and listing, GMP, adverse result reporting, and transparency in labeling Diagnostic test “kits” - reagents, instruments and systems that are developed in the form of a kit and sold by a Device manufacturers Regulated by FDA – subject to premarket review Per CFR: IVDs are reagents, instruments, and systems intended for use: in diagnosis of disease or other conditions, including the determination of the state of health, in order to cure, mitigate gate or treat, or prevent disease and are intended for use in the collection, preparation, and examination of specimens taken from the human body

    15. Pharmacodiagnostics The Hype Surrounding Personalized Medicine Needs to be Balanced Against Many Challenges Research & Development Establishing molecular mechanism and biomarkers Selecting and optimizing diagnostic platforms Clinical specimen acquisition Clinical validation Potential decrease in therapeutic development productivity Relevant biomarker science is often out of step with drug development timing Regulatory Integrated regulatory requirements (e.g., evidentiary standard) are not established and currently inconsistent Regulatory and reimbursement standards within and across major markets (US, EU, and JP) are not harmonized Commercial / Economics Incentives poorly aligned between stakeholders Liability and IP issues Market access for the diagnostic and for therapeutic Physician Education Laboratory Testing Infrastructure, Distribution and Reimbursement Market share and pricing for the therapeutic Diagnostic value and the diagnostic company return on investment

    16. Diagnostic Company (Diag, Inc.) Business Model Diag, Inc. sell diagnostic products, the pharmaceutical company sell drugs Diag, Inc. provides the tools for patients, providers, payers, regulators and pharmaceutical company Constraints to viability of the diagnostic business: A) need for clinical trial as stated by FDA B) cost of clinical trial for clinical validation of a companion pharmacodiagnostic C) relatively low price of reimbursement D) no protection from LDT’s, homebrews E) Diag, Inc. can only survive with Rx support so lack of intrinsic value limits innovation

    17. Pharmacodiagnostic Case Studies Clopidogrel Lung Cancer Abacavir Cetuximab

    18. Polymorphisms: Potential Factors Contributing to Variability of Response to Clopidogrel Clopidogrel has to be converted to an active metabolite (bioactivation) Bioactivation is achieved via P450 enzyme(s)-mediated metabolism CYP2C19, CYP3A4, CYP1A2 and CYP2B6 are involved in bioactivation, Other CYP enzymes are being studied Active metabolite generation may vary through: Drug-drug interaction (e.g. potentially Omeprazole) Polymorphism of CYP 450 enzymes

    19. Mega Study CYP2C19*2 predicts worse outcome 1 or 2 copies of variant No data for other CYP2C19 alleles Gain of function: *17 *1/*1 ~ 40% Caucasian *1/*17 or *17/*17 ~ 35% Caucasian *2/*17 ~ 5% Caucasian Loss of function: *3, *4, *5 All rare in Caucasian *3: 6 % - Chinese *3/ 26% - Japanese Figure 3. Association between Status as a Carrier of a CYP2C19 Reduced-Function Allele and the Primary Efficacy Outcome or Stent Thrombosis in Subjects Receiving Clopidogrel. Among 1459 subjects who were treated with clopidogrel and could be classified as CYP2C19 carriers or noncarriers, the rate of the primary efficacy outcome (a composite of death from cardiovascular causes, myocardial infarction, or stroke) was 12.1% among carriers, as compared with 8.0% among noncarriers (hazard ratio for carriers, 1.53; 95% CI, 1.07 to 2.19) (Panel A). Among 1389 subjects treated with clopidogrel who underwent PCI with stenting, the rate of definite or probable stent thrombosis (a key prespecified secondary outcome, defined as per the Academic Research Consortium) was 2.6% among carriers and 0.8% among noncarriers (hazard ratio, 3.09; 95% CI, 1.19 to 8.00) (Panel B).Figure 3. Association between Status as a Carrier of a CYP2C19 Reduced-Function Allele and the Primary Efficacy Outcome or Stent Thrombosis in Subjects Receiving Clopidogrel. Among 1459 subjects who were treated with clopidogrel and could be classified as CYP2C19 carriers or noncarriers, the rate of the primary efficacy outcome (a composite of death from cardiovascular causes, myocardial infarction, or stroke) was 12.1% among carriers, as compared with 8.0% among noncarriers (hazard ratio for carriers, 1.53; 95% CI, 1.07 to 2.19) (Panel A). Among 1389 subjects treated with clopidogrel who underwent PCI with stenting, the rate of definite or probable stent thrombosis (a key prespecified secondary outcome, defined as per the Academic Research Consortium) was 2.6% among carriers and 0.8% among noncarriers (hazard ratio, 3.09; 95% CI, 1.19 to 8.00) (Panel B).

    20. Simon Study Registry analysis( n=2208) CYP2C19*2*2, not CYP2C19 *1*2 were at risk for a MACE

    21. Emerging information established a role for CYP2C19 in clopidogrel response

    22. Does Variability of Platelet Response correlate to Variability of Clinical Outcomes? Serebruany poses the following questions: (1) Are hypo-responders at higher risk of thrombotic events?, and (2) Are hyper-responders at higher risk of bleeding? (The current study does not provide any data to answer the questions.) Because of the lack of data surrounding hyper-responders and risk of bleeding, this section focuses on hypo-responders and risk of thrombotic events. Variability of platelet response to clopidogrel can be defined by platelet function tests and particularly by measuring inhibition of platelet aggregation to ADP: With clopidogrel 75mg, the targeted median of inhibition of platelet response is between 40 to 60% of platelet inhibition (5µM ADP) The clinical question is: Are hypo-responders at risk of thrombotic events? Are hyper-responders at higher risk of bleeding events? What is the optimal inhibition of platelet response to balance efficacy and safety? To date, no definitive correlation has been established between the level of inhibition of platelet aggregation and the occurrence of clinical outcome events However, defining cut off values that allow identification of outliers is important to optimize management of antiplatelet therapy Serebruany poses the following questions: (1) Are hypo-responders at higher risk of thrombotic events?, and (2) Are hyper-responders at higher risk of bleeding? (The current study does not provide any data to answer the questions.) Because of the lack of data surrounding hyper-responders and risk of bleeding, this section focuses on hypo-responders and risk of thrombotic events. Variability of platelet response to clopidogrel can be defined by platelet function tests and particularly by measuring inhibition of platelet aggregation to ADP: With clopidogrel 75mg, the targeted median of inhibition of platelet response is between 40 to 60% of platelet inhibition (5µM ADP) The clinical question is: Are hypo-responders at risk of thrombotic events? Are hyper-responders at higher risk of bleeding events? What is the optimal inhibition of platelet response to balance efficacy and safety? To date, no definitive correlation has been established between the level of inhibition of platelet aggregation and the occurrence of clinical outcome events However, defining cut off values that allow identification of outliers is important to optimize management of antiplatelet therapy

    23. Outstanding Questions for Genomic Testing for Clopidogrel Therapy

    24. Outstanding Questions for Genomic Testing for Clopidogrel Therapy

    25. Results of PREDICT-I (Mallal et al, New Eng J Med, 2008)

    26. From Research to Clinical Practice: The Abacavir Paradigm*

    27. In HIV, GSK is a big player with its abacavir compound Some patients are hypersensitive to abacavir, with reactions such as fever, rash, gastro symptoms Genetic marker identified and test developed that allowed for screening of patients. Countries where testing became routine commanded higher market shares for abacavir Test costs of $100 were widely reimbursed – most patients at some time would need abacavir Key to drive sales development – drive adoption of the test In HIV, GSK is a big player with its abacavir compound Some patients are hypersensitive to abacavir, with reactions such as fever, rash, gastro symptoms Genetic marker identified and test developed that allowed for screening of patients. Countries where testing became routine commanded higher market shares for abacavir Test costs of $100 were widely reimbursed – most patients at some time would need abacavir Key to drive sales development – drive adoption of the test

    28. Companion Pharmacodiagnostics: individualized medicine in cancer EVOLUTION FROM and Anatomic and DISEASE-BASED TO A MORE PERSONALIZED-BASED MEDICINEEVOLUTION FROM and Anatomic and DISEASE-BASED TO A MORE PERSONALIZED-BASED MEDICINE

    29. Companion Pharmacodiagnostics: individualized medicine in cancer EVOLUTION FROM and Anatomic and DISEASE-BASED TO A MORE PERSONALIZED-BASED MEDICINEEVOLUTION FROM and Anatomic and DISEASE-BASED TO A MORE PERSONALIZED-BASED MEDICINE

    30. Companion Pharmacodiagnostics: individualized medicine in cancer EVOLUTION FROM and Anatomic and DISEASE-BASED TO A MORE PERSONALIZED-BASED MEDICINEEVOLUTION FROM and Anatomic and DISEASE-BASED TO A MORE PERSONALIZED-BASED MEDICINE

    31. Erbitux® (Cetuximab) FDA Approved Indications

    32. History of Companion Drug-Diagnostic Considerations for Cetuximab (2002 - 2007) Early clinical development assumed EGFR expression would be predictive of benefit Specificity of cetuximab for its target Precedent for other targeted mAbs (e.g. trastuzumab, rituxumab) Continuous and dedicated effort by academic and industry scientists to validate EGFR expression as a predictive marker and to further improve patient selection criteria for improved therapeutic index Preclinical models and biomarker discovery Exploratory prospective pharmacogenomic trial Insufficient scientific foundation for prospectively incorporating other predictive markers (e.g. K-ras) at the time that 4 large randomized clinical trials were initiated in 1st, 2nd, & 3rd line treatment for CRC

    33. Key K-Ras Events: April 2008 – July 2009

    34. KRAS Testing and Regulation EU Vectibix and Erbitux are indicated for KRAS WT CRC Approval supported by retrospective data EMEA required a CE marked test Not considered a high risk device by EU directive USA Vectibix and Erbitux label update in 2009 based on safety information – no treatment benefit for patients with KRAS mutations. Treatment not recommended for patients with KRAS mutations Since treatment decisions will be based on test results, a PMA approved kit is required before a efficacy claim on benefit for KRAS WT Considered Class III high risk device FDA approved KRAS test under development

    35. Predictive Biomarkers: Lessons Learned Subgroup analyses – either prospective or retrospective - have become routine Often exploratory but may influence labeling/approval Recent examples of analyses showing associations between biomarker and outcomes have rapidly influenced medical practice Clinical utility of a diagnostic test and level of evidence may be elusive Impact of false + or false – in the context of use How will individualized therapy (e.g., in cancer) be generalized to populations for evidence based medicine Diagnostic Considerations Diagnostic company development – technical and commercial Regulatory approval and oversight Access to the test

    36. Companion Drug-Diagnostic Medicine in the Future Expand and Accelerate the dialogue among stakeholders The macro-environment of companion drug-diagnostics The micro-environment of product development and labeling Flexible process Not a “one size fits all approach” Weighing the evidence Plausibility and relevance of biological underpinning Replication of the observation Provide incentives for the enterprise: Therapeutic and Diagnostic sponsors Patients, Physicians (especially specimen acquisition) Payors Reimbursement for the value of the test-drug combination

    37. Workshop on the Impact of Biomarkers on the Complexity of Drug Development

    38. Conclusions Many challenges remain for predictive medicine to be realized in the future The experiences in these case studies discussed here are likely to be repeated, i.e., post approval scientific discovery leading to clinical application An open dialogue and participation of a broad range of stakeholders is required to bring innovation to clinical and regulatory science to optimize patient selection for new and existing therapies

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