Division of Monoclonal Antibodies Overview

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Division of Monoclonal Antibodies Overview
ACPS Presentation 10/19/04
Steven Kozlowski DMA/OBP/OPS/CDER
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Overview

• Quality Deconstruction Dot Connection
• Biological Characterization
• Research Reviewer Model
• DMA Organization Products
• DMA Ongoing Research
• Critical Path
• Critical Pathways Directions

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Pharmaceutical Quality System
PAT
Drug Safety
Process Capability
Continuous Learning and Improvement
Clinical
CGMPs
Clin Pharm Bio
Controls
CGMP Design Knowledge Space
Pharm/Tox
Clinical Design Knowledge Space
Chemistry
Manufacturing
CMC Design and Knowledge Space
Ajaz Hussain
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A Slice of the Polygon
Clinical
Controls
Chemistry
Manufacturing

• Chemistry to classic analytical controls
• Characterization to release specifications

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ICH Q6B Specifications
TEST PROCEDURES AND ACCEPTANCE CRITERIA FOR
BIOTECHNOLOGICAL /BIOLOGICAL PRODUCTS

• Characterization of a biotechnological or
  biological productis necessary to allow relevant
  specifications to be established.
• Specifications are chosen to confirm the quality
  of the drug substance and drug product rather
  than to establish full characterization and
  should focus on
• those molecular and biological characteristics
  found to be useful in ensuring the safety and
  efficacy of the product.

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The Weakest Links
Clinical
Controls
Chemistry
Manufacturing

• Chemistry to clinical
• Relevant structural attributes (safety
  efficacy)
• Controls to clinical
• Relevant attributes or processes to control

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Overview

• Quality Deconstruction Dot Connection
• Biological Characterization
• Research Reviewer Model
• DMA Products
• DMA Ongoing Research
• Critical Path
• Critical Pathways Directions

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Structure of complex molecules

• 1o sequence
• higher order structure
• post-translational modifications
• heterogeneity

Monoclonal Ab MW 150,000 Da
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ICH Q6BSpecifications for Biotechnology Products
for complex molecules, the physicochemical
information may be extensive but unable to
confirm the higher-order structure
which, however, can be inferred from the
biological activity
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Biological Activity (Q6B)

• the specific ability or capacity of the product
  to achieve a defined biological effect.
• Potency is the quantitative measure of biological
  activity
• Bioassays
• Animal based
• Cell culture based
• Biochemical based
• Other procedures, such as ligand/receptor binding
  assays may be acceptable

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Bioassay Continuum
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How do we choose the relevant biological
activity?
Q6B 2.1.2 Biological activity

• Assessment of the biological properties
  constitutes an equally essential step in
  establishing a complete characterization profile.

Biological Characterization
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Biological Characterization

• Characterization --gt classical specifications
  (Q6B)
• those molecular and biological characteristics
  found to be useful in ensuring the safety and
  efficacy of the product.
• Defining those characteristics relevant to
• Risk management
• CGMPs for the 21st century
• PAT
• Relevant to small molecules

• Molecular mechanism of action
• Biological Plausibility

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Molecular Mechanism of Action

• Therapeutic Proteins potency assays
• All CDER Products facilitate prediction of
• Relevant physiochemical properties
• Toxicity
• Drug interactions
• Efficacy
• May suggest appropriate animal models and
  clinical monitoring

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Biological Plausibility

• Biomarker development/validation
• Interpretation of
• Pharmacogenomic data
• Proteomic data

If Biological Characterization is so important
why is there such variability and limited
guidance on this topic?
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Biological Characterization
Guidance for Industry IND Meetings for Human
Drugs and Biologics EOP2 Biotech

• Adequacy of physicochemical and biological
  characterization (e.g., peptide map, amino acid
  sequence, disulfide linkages, higher order
  structure, glycosylation sites and structures,
  other post-translational modifications, and plans
  for completion, if still incomplete)
• Bioassay (e.g., appropriateness of method,
  specificity, precision)
• Bioactivity of product-related substances and
  product-related impurities relative to desired
  product

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Biological Characterization

• Levels
• Binding conformational changes
• Signal transduction
• Cell culture effects
• Tissue studies
• In vivo studies
• Multiplicity
• Relevant models
• Receptor/pathway/cells/tissues/species
• Molecular mechanism of action (circular)
• No linear algorithm
• Systems approach
• Product specific
• Greater variability in methods
• Expense

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Biological Activity Matrix
Purified/induced variants
Developmental lots
Clinical lot extremes
Stressed lots
Clinical lots
Multiple binding/cellular assays
Small Animal/Complex Bioassay
Clinical/Clin Pharm
Validated bioassay
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Biology Expertise

• A biological characterization is only as good as
  the experimental data supporting it
• If regulatory decisions are impacted by
  biological characterization
• a framework for an appropriate interpretation of
  cell molecular biology information is needed
• This expertise will become more important over
  time
• Guidance for biological characterization
• Mechanism for consultation
• With the recent consolidation, CDER now has
  additional cell molecular biology expertise in
  place.

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Overview

• Quality Deconstruction Dot Connection
• Biological Characterization
• Research Reviewer Model
• DMA Products
• DMA Ongoing Research
• Critical Path
• Critical Pathways Directions

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Researcher Reviewer Model
Pleiotropy

• Awareness of the nuts bolts of many review
  issues
• Multiplicity is a challenge
• Research producivity
• PCE
• Regulatory workload
• Investigator independence relevance

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Researcher Reviewer Model
Catalysis Synergy

• Not all reviewers can have active research
  programs
• A small nucleus can encourage
• biochemical/biological characterization
• process understanding
• mechanistic consideration
• This group can consult when a key decision is
  dependent on biological characterization
• This may include evaluating the validity of
  experimental data used to support the molecular
  mechanism of action
• The research reviewer group can network
• NIH and other academic experts
• OTR staff
• Full time review staff

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Research Organization
A Tapestry
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Overview

• Quality Deconstruction Dot Connection
• Biological Characterization
• Research Reviewer Model
• DMA Organization Products
• DMA Ongoing Research
• Critical Path
• Critical Pathways Directions

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DMA Organization
Lymphocyte and monocyte biology Tumor suppressors
and oncogenes
Manufacturing process validation
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Initial Indications for Licensed Monoclonal
Antibodies
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Approved Products

• Biological Response Modifiers

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Approved Products
Oncological Therapeutic Drugs
Product reviewers participate in PAIs in
biennials
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Approved Products
Radio-immuno-imaging Agents

• PTC for MAb
• Plant Transgenic Products
• Orphan Drug Status MAb
• Use of MAb as a Reagent for Further Manufacture

• Scientific Considerations for Follow on Proteins
• Stakeholder mtg
• DIA mtg
• Q5E

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Overview

• Quality Deconstruction Dot Connection
• Biological Characterization
• Research Reviewer Model
• DMA Products
• DMA Ongoing Research
• Critical Path
• Critical Pathways Directions

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Research Areas
Clinical
Controls
Chemistry
Manufacturing

• Structure
• TNF multimerization effects (Dr. Kathleen Clouse,
  Ph.D.)
• Use of SPR in protein thermodynamics (Dr. Steven
  Kozlowski, M.D)
• Antibody Structure

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IgG Structure
V region CDRs
Jefferis et al. Immunology Letters (2002) 82
57-65. PDB 2IG2, 1FC1
FcgRI,II,III C1q
FcRn MBL MR
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Antibody Structural Diversity
Dr. Marjorie Shapiro, Ph.D.

• A number of molecular processes are involved to
  generate a mature specificity
• V(D)J Recombination
• Switch Recombination
• Somatic Mutation
• Positive and negative selection in a normal
  microenvironment
• New technologies
• Phage display
• Transgenic animals expressing human ab genes

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Antibody Structure Immunogenicity

• Murine n8
• Whole antibodies
• 55 to gt80
• Fab or Fab
• lt1 to 8
• Chimeric, n5, 3/5 whole mAbs, 1 Fab
• lt1 to 13
• Humanized, n7, whole antibodies
• lt1 to 8
• Human (f display), n1
• 12

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Antibody Effector Interactions
Dr. Mate Tolnay, Ph.D.

• Complement receptors play a critical role in
  antibody function and production
• A new family of FcR-like genes may play a role in
  antibody effector function

Dr. Gerald Feldman, Ph.D.

• Immune complex-mediated regulation of cell
  function as a side effect of Ab treatment

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Research Areas
Clinical
Controls
Chemistry
Manufacturing

• Biological Characterization
• In vitro
• In vivo

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Adhesion CostimulationSteven Kozlowski, M.D.
Selective Effects on CD8 versus CD4 T-cells
Keratinocyte proliferation
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Lymphocyte Signaling Barbara Rellahan, Ph.D.
Cbl participates in Herceptin response
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Cytokines Sustain HIV Reservoir
Dr. Kathleen Clouse, Ph.D.
HIV
HIV infected macrophage
PDI Viral entry
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GTPase Cycle Targets Neoplasia
Wen Jin Wu, M.D. Ph.D.
Erbitux
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Epithelial Differentiation NeoplasiaWendy
Weinberg, Ph.D.
p53 family members play distinct roles in
regulation of cell growth, differentiation and
cancer pathology
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Research Areas
Clinical
Controls
Chemistry
Manufacturing

• Contaminants
• Process Understanding

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Prion Peptide Cell Signaling
Dr. Gerald Feldman, Ph.D.

• NF-kB pathway
• Cytokine Induction

• On DCs
• Activation and maturation
• Lack of calcium flux
• Resistance to PT
• No involvement of FPRL-1

• On Monocytes
• Chemotactic
• Induction of calcium flux
• Sensitivity to PT
• Involvement of the FPRL-1

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Contamination Process Control Kurt Brorson,
Ph.D.

• Retroviral testing
• implementation of Q-PCR based assays
• Process understanding
• unit operation robustness predictability-
  chromatography, membrane adsorbers, fermentation,
  virus inactivation

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Cell Culture Process Changes
Which of these can impact endogenous retrovirus
expression?
Photo courtesy of Applikon, Inc.
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Overview

• Quality Deconstruction Dot Connection
• Biological Characterization
• Research Reviewer Model
• DMA Products
• DMA Ongoing Research
• Critical Path
• Critical Pathways Directions

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Critical Path
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Critical Path

• A. The technical hurdle or problem
• Dimensions of product development
• Unique vantage point of FDA
• Industry segments facing the problem
• - role of partnerships/collaborations
• The government role in solving this problem
• Solution impact on product development
• - breadth of solution on products/classes/sector
  s

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Critical Path David Frucht, M.D., LCB

1. Problem Limited bioassays for anthrax lethal
   toxin activity and neutralization
2. questionable relevance to the in vivo mechanism
3. widely accepted assays involve analysis of the
   viability of two murine macrophage cell lines
4. murine but not human cell lines undergo apoptosis
   in response to anthrax lethal toxin
5. appropriate bioassays are critical since that it
   is not feasible to assess the efficacy of anthrax
   therapeutics in humans directly (Animal Rule).
6. in vitro potency assays involving human cells or
   cell lines are more likely to be of predictive
   value for efficacy in humans
7. Dimensions Medical Utility Industrialization

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Critical Path David Frucht, M.D.

• FDA unique vantage the FDA is
• evaluating several INDs for anthrax therapeutics
• involved in the discussions regarding the
  stockpiling of anthrax therapeutics for Project
  BioShield.
• in a unique position to compare cell-based
  bioassays for anthrax lethal toxin
• Industry segments/partnerships
• small large biotechnology and pharmaceutical
  companies are developing products targeting
  anthrax
• academic collaborationsinternal expertise CDC
  NIH interactions additional public-private
  partnerships can be developed.

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Critical Path David Frucht, M.D.

• The government role
• BioShield regulator stakeholder
• IND product awareness
• internal expertise
• anthrax lethal toxin activates a pro-inflammatory
  cytokine pathway involving the enzyme caspase-1
  and its downstream effectors IL-1? and IL-18.
  This assay is more sensitive than existing assays
  examining cell viability.
• although human macrophages and macrophage cell
  lines are resistant to anthrax LT-induced cell
  death, the caspase- 1/IL-1?/IL-18 cytokine
  pathways are highly activated and readily
  detectable.
• Impact a relevant toxin assay helps to assure
• development and quality of efficacious products
• recognition of more suitable biomarkers for
  infection
• impacts the companies currently developing
  anthrax therapeutics, other toxin therapies and
  the public health

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Molecular Mechanism of Anthrax ToxinDavid
Frucht, M.D.
IL-1b and IL-18 Release In vitro and in vivo
(Frucht lab)
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Critical Path Wendy Weinberg, Ph.D.

1. Problem the need for animal models with higher
   predictive value for drug effectiveness
2. models applied to development and evaluation of
   effective cancer treatments should reflect the
   molecular changes contributing to cancer
   evolution.
3. transgenic mice with inducible expression of
   commonly mutated genes provide a more physiologic
   context of tumor development that is
   representative of the human situation than models
   commonly utilized by drug developers.
4. Dimensions Medical Utility

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Critical Path Wendy Weinberg, Ph.D.

• FDA unique vantage the FDA is
• evaluating numerous INDs/NDAs/BLAs for cancer
  therapeutics
• in a unique position to compare in vivo and in
  vitro assays used to demonstrate product activity
• Industry segments/partnerships
• numerous biotechnology and pharmaceutical
  companies are developing products targeting
  cancers
• failed phase 3 studies for oncology products may
  have been prevented by better animal models
• academic collaborationsinternal expertise
  additional public-private partnerships can be
  developed.

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Critical Path Wendy Weinberg, Ph.D.

• The government role
• product awareness
• internal expertise
• experience in animal models of epithelial cancers
  that appropriately reflects the genetic changes
  observed in human cancer pathogenesis.
• the most frequently altered pathway in human
  cancers is that of the nuclear transcription
  factor p53 recently a related protein p63 has
  been identified that can modulate p53 activity
  and also act independent of p53 to alter growth
  properties of cells.
• the contribution of specific p63 isotypes will be
  determined in combination with additional changes
  such as p53 mutations (as observed in lung
  cancer), the presence of human papilloma virus
  (HPV) (as seen in cervical and some oral
  cancers), and her2 neu overexpression (as in
  breast cancers)
• Impact this project helps to assure
• development of animal models reflective of human
  cancers
• impacts a very large segment of the industry

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Critical Path Kurt Brorson, Ph.D.

• Problem the need for less expensive strategies
  to assure viral safety
• Mammalian cells used in the production of
  monoclonal antibodies (mAbs) produce endogenous
  type C retrovirus particles and are capable of
  being infected by adventitious agents.
• Regulatory agencies require a demonstration that
  mAbs intended for human use are free of virus
  with an adequate margin of safety.
• Small scale viral clearance studies can be
  prohibitively expensive for small biotech firms
  and academic investigators
• Dimensions Safety Industrialization
• FDA unique vantage This problem has been
• communicated to the agency at conferences
• noted in review of multiple INDs.

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Critical Path Kurt Brorson, Ph.D.

• It impacts multiple sponsors of biotech INDs,
  particularly small biotech firms and academic
  investigators.
• The government role
• government can provide a broad perspective for
  identifying acceptable solutions and approaches
  that comply with GMP standards
• industry-government collaboration may facilitate
  solution of this issue by pooling resources and
  expertise
• work on membrane absorbers and viral clearance
  will be part of a larger collaborative study
  concerning virus membrane interactions with
  Genentech, the University of Maryland, Baltimore
  County and the University of Wisconsin, Madison

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Critical Path Kurt Brorson, Ph.D.

• Impact this project helps to assure
• lower barriers against innovation by biotech
  companies
• regulatory relief for these organizations

• In earlier collaborative studies, Genentech Inc.
  and the Division of Monoclonal Antibodies
  performed two matrix/bracket studies of robust
  viral clearance steps (e.g. low pH inactivation
  and anion exchange chromatography Brorson et
  al., Biotechnol Bioeng 82321-9 Curtis et al.
  Biotechnol Bioeng 84179-186, 2003).

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PR772- suitability for testing large virus filters
Genome sequence resolved- AY441783 Highly similar
to other Tectiviridae
150,000 x
Lute et al., Appl. Environ. Microbiol. 704864,
2004
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Critical Path Kurt Brorson, Ph.D.
Dimensions Safety Industrialization

• Gene arrays, cell culture process changes, and
  comparability
• Chromatography media decay and virus removal
  validation
• Databases of viral clearance experience and TSE
  risk (with Gerry Feldman, Ph.D.)

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Overview

• Quality Deconstruction Dot Connection
• Biological Characterization
• Research Reviewer Model
• DMA Products
• DMA Ongoing Research
• Critical Path
• Critical Pathways Directions

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Critical Pathways
Cell Molecular Biology

• Toxicity
• Drug interactions
• Efficacy

• May suggest appropriate animal models and
  clinical monitoring

Manufacturing process validation
Regulatory relief fewer failed studies
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Critical directions

• Better define biological characterization
• eventual guidance
• role for follow on proteins
• Maintaining OBP biological expertise and research
  across relevant areas of biology for our products
  (critical pathways)
• Facilitating access to between OBP biologists
• interactions with other OPS offices, pharmacology
  and clinical review groups
• Biotech Rounds
• MAJIC/ Bioprocessing Journal Club
• mechanism for consults

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Critical directions

• Extending some OBP research into defined Critical
  Path projects
• Relational databases
• viral clearance (Kurt Brorson)
• review management, USAN, targets (Patrick Swann)
• specifications (Patrick Swann)
• TSE (Gerry Feldman Kurt Brorson)
• internal meetings
• workload
• structural/sequence information
• Enhancing safety facilitating regulatory relief