Biotechnology Drugs

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Biotechnology Drugs

• Part I Basic concepts
• Part II Process Quality Safety issues
• Part III A checklist for inspection

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Why Are Biotechnology Products Different From
Simple Organic Chemicals?

• Synthetic Drugs
• Small molecules
• Easy synthesis
• Aspirin
• Oligopeptides
• Hemi-synthesis
• Need of active stereo-isomers
• Steroids
• Anticancer
• Antimetabolites
• cyclosporin

• Extraction Biologicals
• Complex rare molecules
• Animal source possible
• Insulin
• Heparins
• Human source necessary
• HGH
• Coag. Factors
• Albumin

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Biotech Drugs

• Better yield better safety
• Insulin
• HGH
• Modified molecules
• Extraction impossible
• Erythropoietin
• Interferon
• Interleukin
• Growth factors

4
Manufacturing Processes Are Different

• Biotech Products
• Produced by purification
• Starting material variable
• Many in-process tests
• End-product tests complex
• Process is product-specific
• Batch sizes small (g or kg of finished product)

• Conventional drugs
• Produced by formulation
• Starting material defined
• Few in-process tests
• End-product tests simple
• Process is product type specific (generalizations
  possible)

5
Biotechnology Drugs

• Use of micro-organisms (procaryotic or
  eucaryotic) genetically modified for production
  of complex molecules
• After purification, the products are used in
  human or animal therapeutics

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Medicinal Products Derived From Recombinant DNA

• Insertion of naturally occurring or synthetic
  nucleotide sequence into a vector
• Introduced into a suitable host organism to
  ensure the efficient expression of the desired
  gene product

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Five Features For a Biotechnology Drug

1. Expression system of the gene
2. Production system compatible with the
   microorganism
3. Purification system
4. Nature of the active product
5. Pharmaceutical formulation and presentation

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Five Features For a Biotechnology Drug1.
Expression System Vector Host

• Identify, isolate and clone the gene coding for
  the desired protein
• Construct a vector containing
• The gene
• The expression controls (promoter, secretion
  signal)
• Insert the vector into the selected
  micro-organism
• Escherichia coli
• Saccharomyces cerevisiae
• Mammalian cells
• Genetically modified plants

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Expression System Vector Construction Host
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Five Features For a Biotechnology Drug2. The
Production System

• Purpose
• Optimize survival conditions for the genetically
  modified microorganism
• So that it produces the desired protein
• With acceptable yield
• Materials Methods
• Selection of cell culture medium
• Selection of culture conditions
• Selection of culture equipmentsfermentor,
  cytocultor

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Five Features For a Biotechnology Drug3. The
Purification System

• Purpose
• extract protein from a complex growth medium
• Achieve close to 100 purity
• Without altering the protein
• Materials Methods
• Sequence of purification steps
• Filtration/ultrafiltration
• Precipitation/resolubilization
• Chromatography (ion-exchange, affinity, etc.)

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Five Features For a Biotechnology Drug4. Nature
of Active Product

• Proteins
• Chains of amino-acids
• Sequence of amino-acids encoded by genes
• Folded into 3-D conformation
• To obtain biological activity
• Host-dependent post-translational modifications
  (sugars)

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Five Features For a Biotechnology Drug5.
Pharmaceutical Formulation and Presentation

• Purpose
• Maintain biological activity
• By maintaining active protein conformation in
  solution
• Materials Methods
• Stabilization (albumin, glycerol)
• Storage at low temperature

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Biotechnology Drugs

• Part I Basic concepts
• Part II Process Quality Safety issues
• Part III A checklist for inspection

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Process Flow-Chart
Fermentation- culture
Harvest
Starting material
Purification
Pharmaceutical finishing
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A Cell Bank

• A collection of ampoules of uniform composition
  stored under defined conditions, each containing
  an aliquot of a single pool of cells

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The Master Cell Bank (MCB)

• Generally derived from the selected cell clone
  containing the expression construct.
• The MCB is used to derive all working cell banks.

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The Manufacturer Working Cell Bank (MWCB)

• Derived by expansion of one or more ampoules of
  the MCB under defined culture conditions
• The working cell bank is used for the production
  of the batches.

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The Late Expanded Cell Bank (LECB)

• Obtained in multiplying the cells used for the
  production of the recombinant protein, several
  passage after the passage of production.
• It is used to reveal a potential low viral
  contamination and to study genetic stability of
  the transgene.

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Cell Bank System
Genetic transformation
Parental cell line
Master cell bank (MCB)
expand
Starting material
Manufacturer working cell bank (MWCB)
expand
Production substrate
expand
Late expanded cell bank (LECB)
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Cell Bank System
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Process Flow-Chart
Fermentation- culture

• Various expansion systems
• (fermentor, roller bottle, fermenting flasks,
• Cell culture systems, airlift, hollow fiber
• Various culture media
• (totally synthetic or containing components
• of animal origin)

Starting material
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Process Flow-Chart
Fermentation- culture
Harvest
Starting material

• Discontinuous production system
• (from fermentor)
• Continuous production system
• (several harvests of culture supernatant)

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Process Flow-Chart
Fermentation- culture
Harvest
Starting material
Purification

• Various extraction strategies
• (from supernatant or cell disruption)
• Various purification methods
• (according to potential contaminants)

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Purification Potential Contaminants

• What contaminants may be encountered?
• What is the source of the contamination?
• How hazardous are they?
• How can they be removed?
• How can we ensure their removal?

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Purification Potential Contaminants

• Process-related impurities
• Cell substrate derived
• Cell culture derived
• Downstream derived

• Product-related impurities
• Truncated forms
• Other modified forms
• aggregates

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Purification Potential Contaminants

• Microbiological contaminantsadventitious agents
• Prevent in the original cells or in the master
  cell bank
• Adventitious viruses introduced during production

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Purification Potential Contaminants

• Hazards
• Toxicity
• Heavy metals, cyanogen bromide, antibiotics,
  organic solvents
• Altered pharmacological activity
• Aggregates, breakdown products
• Immunogenicity
• Oncogenicity
• Infectious diseases
• Mycoplasmas, yeasts, viruses

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Purification Contaminant Removal

• A sequence of several methods
• Precipitation
• Filtration
• Liquid chromatography based on different physical
  or chemical principles
• Affinity, hydrophobicity, molecular weight,
  electrical charge

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Biotechnology Drugs

• Part I Basic concepts
• Part II Process Quality Safety issues
• Part III A checklist for inspection

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Purification System Should Be

• Appropriate
• Justified
• Validated

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Process Flow-Chart
Fermentation- culture
Harvest
Starting material
Purification
Pharmaceutical finishing

• Stabilization
• (according to protein and delivery mode)
• Storge

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A Checklist For Inspection

• Focus on changes in the manufacturing process
• Do not classify a priori a change in the process
  as minor or major
• Consider the potential consequences on the drug
  product in terms of
• Quality
• Safety
• Efficacy

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Changes In the Manufacturing Process

• Main reasons for introducing changes
• Improvement of product quality
• Increase of production yield
• Global productivity
• Cost savings
• Production scale-up
• New production sites

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A Checklist For Inspection

• 1.Cell bank system
• 2.Fermentation/culture process
• 3.Purification process
• 4.Drug substance
• 5.Formulating and filling
• 6.Drug product

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Issues For Inspection1.Cell Bank System

• GMP compliant plant design
• Documentation of cell origin
• Setup conditions for the (Master), (working) and
  (late expanded) cell banks
• Documentation of viral safety
• Documentation of expansion conditions
• Storage conditions
• Measures taken against contamination

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Issues For Inspection2.Fermentation/Culture
Process

• Starting material (cells)
• New supplier
• Specifications
• Additions/substitution of new material
• Cell culture conditions
• pH, oxygen, temperature, time, of reagents,
  formulation of culture media
• Scale of fermentation/cell culture mode
• Equipment
• Change of additional fermentation site or
  facility

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Issues For Inspection3.Purification Process

• Column/resin change
• Size of column, supplier, cleaning conditions,
  storage conditions
• Reagents
• New supplier, specifications, replacement of raw
  material
• Purification protocols
• Addition/substitution/elimination of specific
  steps
• Scale of the downstream processing
• equipment

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Issues For Inspection4.Drug Substance(active
principle)

• Batch definition
• Storage conditions
• Pooling strategy

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Issues For Inspection5.Formulating and Filling

• Excipient
• Equipment
• Manufacturing process
• Scale
• Change of site/facility
• Storage shipping conditions

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Issues For Inspection6.Drug Product (final
product)

• Control of
• Identity
• Purity
• Activity
• Stability
• General safety
• Sterility
• pyrogenicity

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Issues For InspectionSummary

• Clean starting material
• Well-characterized cell-line
• (cell bank) system
• Validated production purification processed
• (In-process) controls
• Specific final products testing
• Compliance to GMPs

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Conclusion

• The growing number of biotechnology products
  requires highly skilled professionals to inspect
  complex and changing production processes