What Physiologists Working in Industry Do Physiologists in Industry Committee (PIC) American Physiological Society Objective The purpose of this presentation is to 1) inform you about the responsibilities and types of work a Physiologist performs as a member of the pharmaceutical, biotech, or nutritional industry; and 2) describe some of the primary personal attributes necessary to succeed in this environment. Science and Drug Discovery • The drug discovery process requires concerted efforts of scientists across many disciplines (Biochemists, Chemists, Molecular Biologists, Pharmacologists, Physiologists, Technologists, etc…) to advance a project from initial scientific principles (an idea or hypothesis) to a clinical candidate, and ultimately a drug to treat human disease. • This extremely challenging undertaking is pursued under strict guidelines regulated by federal (i.e. FDA, USDA) and international (EMEA) agencies. Successful drug discovery requires critical thinking, organizational skills, creativity, as well as flexibility and resourcefulness. • In short, success in drug discovery requires well-trained, disciplined, and rigorous scientists. The process is one in which Physiologists can assume many critical roles. Do you fit these criteria? Scope of Scientific Activities of Physiologists in Drug Discovery Activities are listed from first discovery principles (hypothesis generation and testing) to clinical trials and submission of an NDA (New Drug Application) Target discovery and validation Proof-of-concept studies Development of in vitro efficacy models Mechanism of compound action Development of in vivo models (normal function and disease) Pharmacokinetic studies Pharmacodynamic studies Assay development Ex vivo functional studies Disease efficacy testing Development and utilization of biomarkers Safety pharmacology Interpretation of clinical results Exploration of additional indications Regulatory submission for product and claim approval Description of Bench Science Activities of Physiologists in Industry (Part I) Target Discovery and Validation: Studies of disease mechanisms using molecular and genomic approaches including genetic association studies in humans, knockout and transgenic animals, engineered tool compounds to identify or confirm a biochemical target Proof-of-Concept Studies: Studies are conducted to address the questions: does the enzyme, receptor, channel, etc… play a role in the physiological or disease process? Is the target of interest be activated/inactivated in this process? In Vitro Efficacy Testing: Develop and use assays to test the hypothesis in simple systems such as isolated proteins and/or cell-based systems. These assays may often use high-throughput or multiplexed (multiple readouts) platforms. Examples of Bench Science Activities of Physiologists in Industry (Part II) Mechanism of Compound Action: Studies are designed to address questions such as does the compound affect enzyme, ion channel, or receptor activity? Does the compound affect a specific signaling pathway? Does the compound affect genetic regulation (expression) of the target? Development of Disease Models: Studies are designed to address questions such as: does the cell, tissue, or animal model resemble the human condition? Is the model valid? (i.e. does the pathophysiology respond to current pharmacotherapies?) Examples of Bench Science Activities of Physiologists in Industry (Part III) Pharmacokinetic (PK) Studies: generally considered in terms of “what the organism does to drug” and studies are designed to address questions such as: what is the maximal plasma concentration of drug after dosing and when does this occur? how much drug gets to the tissue of interest and how widely is the drug distributed in the body? how quickly is the drug cleared after dosing? Pharmacodynamic (PD) Studies: generally considered in terms of “what the compound does to the organism” and studies are designed to address questions such as: is the biochemical target affected by the compound and to what extent? Is the tissue of interest affected? Examples of Bench Science Activities of Physiologists in Industry (Part IV) Ex vivo functional studies: Evaluation of integrated tissue or whole organ function with ability to carefully control dose, duration, and exposure to compound (e.g. isolated working heart, isolated perfused kidney, isolated blood vessel, brain slice, etc…) Disease efficacy testing: Acute and/or chronic studies are conducted to address questions such as: does the compound modify disease progression in vivo (i.e. prevention model)? Can the compound regress the disease (treatment model)? How does the efficacy of the compound compare to existing pharmacotherapies or potential co-therapies? Development and utilization of biomarkers: Studies are conducted to investigate whether there a quantifiable blood or urinary biochemical marker that predicts severity or progression of the disease? Can the marker serve as a surrogate for long-term efficacy of the compound? Examples of Bench Science Activities of Physiologists in Industry (pt V) Exploration of additional indications: Evaluate experimental results and literature to determine whether additional scientific opportunities exist (i.e. does the mechanism of action or signaling pathway play a role in other conditions other than the primary indication?) Interpretation of clinical results: mechanistic and/or theoretical evaluation of unexpected clinical events (utilization and identification of appropriate biomarkers to track mechanistic or pathophysiological responses to agent). Preclinical safety pharmacology: Studies are designed to address questions such as: what is the therapeutic index of the compound? What is the incidence of adverse events in major organ systems (e.g. cardiovascular, renal, gastrointestinal, respiratory, CNS) at multiples (3x, 10x, 30x) of therapeutic plasma concentrations of the compound? Non-Bench Science Activities of Physiologists in Industry Industry scientists have many responsibilities beyond benchwork… Training and supervision of technical staff Generation of novel scientific and technical hypotheses Rigorous design, analysis, and interpretation of experiments Presentation of scientific concepts and business applications of research to various professionals to enable business and scientific decisions Participation in project team and strategic planning meetings Writing of technical reports and scientific manuscripts Documentation of all scientific observations and submitting patents Planning facility development and resource (people, space, equipment) deployment Participation in the preparation and submission of documents (IND: Investigational New Drug; NDA: New Drug Application) to the Food & Drug Administration (FDA) Personal Attributes of Successful Industry Scientists (Part I) To be successful in discovering and developing a new drug, you must participate in a process that requires concerted efforts by many people across many departments and disciplines. Specific attributes are required to succeed in this fast-paced environment… Critical Thinking: Industry scientists identify key issues and deliver timely scientific responses to discovery projects and business development opportunities Team and Collaborative Behavior: Industry scientists network with internal/external scientists to assure access to current and innovative technologies and scientific advances. Interpersonal Skills: The drug discovery and development process is a huge undertaking, successful industry scientists foster a cooperative spirit, and work well with other scientific, regulatory, clinical, and business professionals. Personal Attributes of Successful Industry Scientists (Part II) Strong Communication Skills: Effective communication of ideas whether one on one, in small groups, or through formal presentations. Writing is clear, well-organized and logically developed; the audience is taken into consideration. Efficiency: The demands on an industry scientist are many (various experimental models to run and multiple compounds to test). Thus, industry scientists are constantly challenged to implement new processes to streamline procedures while maintaining rigorous standards. Flexibility: Effectively initiates change as needed and adapts to necessary changes in operations or strategies; also initiates new ways of accomplishing work. Leadership: Industry scientists drive operational plans and develop and implement tactics to deliver results by set timelines. Leads by appropriate actions and behaviors; inspires and guides others to achieve corporate and personal goals. Physiologists in Industry: Target Discovery and Validation Target discovery studies investigate disease mechanisms using molecular and genomic approaches in knockout and transgenic animals. Physiologists use these approaches to identify or confirm a role for biochemical targets in organ and organism function and dysfunction. Below: gene knockout of PKC improves cardiac performance following pressure overload (TAC), while transgenic overexpression of PKC impairs cardiac performance. PKC knockout (Prkca -/-) mice have enhanced cardiac ventricular performance Overexpression of PKC (Prkca) in transgenic mice reduces cardiac ventricular performance Reprinted with permission from Braz et al. Nature Med 10(3), 2004 Physiologists in Industry: Proof-of Concept Studies Proof-of-concept studies address whether a biochemical target plays a role in a disease process (i.e. is the target of interest activated, inhibited or differentially expressed in disease?) Physiologists use various approaches to learn whether a biochemical target is involved in disease. Lower left panel: over-expression of the cardiac enzyme, calcineurin (CN) transgenic mouse, induces cardiac hypertrophy; lower right panel: aortic-banding increases cardiac CN expression (A) and activity (B), treatment with CsA, a CN, inhibitor prevents aortic-banding induced cardiac hypertrophy (C). C Reprinted with permission from Molkentin Circ Res 87, 2000 Reprinted with permission from Lim et al. Circulation 101, 2000 Physiologists in Industry: In Vitro Efficacy Testing In vitro efficacy studies employ assays utilizing simple systems (e.g. isolated proteins and/or cell-based systems). These preparations allow Physiologists to carefully control experimental conditions and compound concentrations while measuring and comparing responses and behaviors of large numbers of compounds. Below: a classical competition curve utilizes radioligand binding techniques to evaluate the ability of compound Y to compete for receptor subtype binding, in turn generating affinity and potency data. [H3] Ligand Bound (% control) Compound Y Competition vs. Receptor Subtypes 1 and 2 100 75 50 IC50 (nM) 25 0 -13 subtype 1 0.24 0.04 subtype 2 0.30 0.04 Cmpnd Y vs 1 170 92 Cmpnd Y vs 2 40 21 -12 -11 -10 -9 -8 [Compound], M -7 -6 -5 Physiologists in Industry: Mechanism(s) of Compound Action 100 response to Angiotensin I bolus % inhibition of the mean arterial pressure Enalapril blocks the blood pressure response to Angiotensin I: The mechanism of action is the antagonism of angiotensin converting enzyme 80 60 40 20 0 -120 -60 Enalapril (10 mg/kg) 0 60 Angiotensin I (300 ng/kg, IV) 120 180 Time (min) 240 300 360 Physiologists in Industry: Development of Disease Models Ultimately, drugs developed through the discovery process must be able to modify disease progression and outcome. Physiologists develop models of disease for drug discovery, and must have an thorough understanding of normal and pathologic ranges of functional parameters. A valid disease model must involve many of the critical biochemical pathways and display many clinical findings of the human disease state. Below: Surgical instrumentation and induction of chronic pacing-induced heart failure. Surgical Instrumentation Pacing-Induced HF and Recovery 1. 2. 3. Cardiac function and coronary flow are measured in the conscious state by chronic instrumentation. Heart failure (elevated end diastolic pressure, reduced ejection fraction and cardiac reserve) is induced by right ventricular pacing for 3-4 weeks. Recovery from heart failure is allowed by the termination of pacing for 5-6 weeks after developed heart failure. Physiologists in Industry: Pharmacokinetic Studies Pharmacokinetic studies characterize how the body handles a compound. Physiologists work alongside Medicinal and Bioanalytical Chemists to determine if a compound is orally bioavailable and will achieve adequate plasma and tissue exposure and duration prior to undertaking an efficacy or chronic disease modification study. Below: Oral administration of Compound X (10 mpk) exhibited good fractional bioavailability (F% = 54%) and plasma halflife (t1/2 = 6 hours). Pharmacokinetic Characterization of Compound X Plasma Concentration (pg/ml) 1500 iv dose (10 mpk) oral dose (10 mpk) 1250 i.v. dose Cmax = 1004 pg/ml 1000 oral dose Cmax = 535 pg/ml; Tmax = 3 hrs, F = 53% 750 500 t1/2 = ~6 hrs 250 0 0 4 8 12 16 Time (hrs. post-dosing) 20 24 Physiologists in Industry: Pharmacodynamic Studies Pharmacodynamic studies characterize the effects of a compound on the body. Certain enzymes are activated (e.g. phosphorylated) or modified (e.g. glycosylated) in disease processes. For example, to determine if a compound will inhibit an enzyme of interest, Physiologists determine whether enzyme phosphorylation and kinase activity are suitable pharmacodynamic indices for compound activity. Below: intraperitoneal administration of a physiological stimulus dose-dependently increased enzyme phosphorylation and kinase activity, providing a model to assay compound activity against this enzyme’s activity. Western Blot – Phosphorylated Enzyme vehicle 3 mpk Immunoprecipitation Kinase Assay 10 mpk 35000 p-TXXX * p < 0.01 vs. vehicle * p-TXXX / Total enzyme 0.12 * * p < 0.01 vs. vehicle 0.10 * 0.08 0.06 0.04 Counts per Minute 30000 Total Enzyme * 25000 20000 15000 10000 5000 0.02 0 Vehicle 0.00 vehicle 3 mpk 10 mpk 3 mpk 10 mpk Physiologists in Industry: Ex Vivo Functional Studies Ex vivo studies evaluate integrated organs and organ systems from normal and diseased organisms. These preparations allow Physiologists to carefully control experimental conditions and organ compound exposures while measuring and comparing functional responses in normal and diseased organs. Below: an isolated working heart preparation allows careful control of preload, afterload, heart rate, and compound exposure. Cardiac Systolic Performance Endpoints LV Systolic Pressure mmHg LV End Diastolic Pressure mmHg Left Atrial Pressure mmHg Aortic Mean Pressure mmHg Max +/-dP/dt mmHg/sec Peak Pressure mmHg Time to Peak Press (TPP) msec TPP/PP msec/mmHg Diastolic Function Endpoints tau msec 1/2 Relaxation Press (1/2 RP) mmHg 1/2 Relaxation Time (RT1/2) msec (RT1/2) / (1/2 RP) msec/mmHg Physiologists in Industry: Disease Efficacy Studies Drugs developed through the discovery process must show efficacy in modifying disease progression and outcome. Physiologists develop models of disease for drug discovery, and are required to have a thorough understanding of normal function as well as the pathology of disease states. Last, models of human diseases for drug discovery must be amenable to standard pharmacotherapies. Below: Effects of varying delay (7 day vs. 30 days post-MI) of ACE inhibitor treatment on a) survival, b) cardiac hemodynamics, and c) morphology after myocardial infarction (MI). b a untreated ACEi 30d post-MI ACEi 7d post-MI Reprinted with permission from Mulder et al. Circulation 95, 1997 c Physiologists in Industry: Development and Utilization of Biomarkers Blood and/or urinary biochemical markers that are correlated to disease severity allow tracking of disease progression and regression following drug therapy. Physiologists a) develop disease models that have biomarker profiles similar to those observed in human disease, b) evaluate biomarker responses to standard and novel therapeutic agents, and c) develop assays to quantify biomarkers. Below: Kaplan-Meier survival curve for mortality and morbidity in human heart failure patients based on plasma brain natriuretic peptide (BNP) concentrations. Thus, plasma BNP is associated with disease severity and may be used in place of more expensive and timeconsuming assays. Reprinted with permission from Anand et al. Circulation 107, 2003 Physiologists in Industry: Preclinical Safety Pharmacology • Studies can be designed to address specific questions regarding safety of a compound with respect to a) acute plasma concentrations of drug (does increasing the plasma concentration of a drug 10-fold above the therapeutic level induce cardiac electrophysiological abnormalities?) or b) following chronic dosing. For example: • Determine the effects of increasing drug concentrations after dosing for 7 or 28 days various organ function, morphology, and histology • Determine “No Adverse Events Level” (NOEL) for compound • Federally required data in 2 species before First Time in Human (FIH) testing