Jeffrey L. Shumway
MilliporeSigma
Excipientfest – Providence, RI
April 26, 2017
ExcipientS: Critical Components of the BiomanufacturingProcess
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
CLASSIC PERSPECTIVE
4
The Bioprocess Perspective
FORMULATION
PURIFICATION
A DIFFERENT PERSPECTIVE
CONTINUOUS FORMULATION
5
Chemistries of the recombinant/mAb process and formulation
Protein refolding
Virus Inactivation Chromatography Formulation
Urea
Ultra/Diafiltration
Glutathione
Arginine/Cysteine
Ammonium sulfate
Acetate
Citrate
Glycine
Triton™ X-100
Tri-N-Butylphosphate
Tris/Tris HCl
Glycine
Ammonium sulfate
Sodium Chloride
Urea
Ethanol (storage)
Sorbitol/Mannitol
Sucrose
Sodium Chloride
Histidine
Polysorbate 20/80
Citrate
Acetate Acetate
Citrate
Phosphate Phosphate
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
7
Administration of biomolecule therapeutics
Parenteral Administration• Intravenous• Direct Injection
• Infusion
• Subcutaneous
• Intramuscular
• Intradermal
• Intraspinal
• Intrathecal
• Intra-arterial
• Others
8
Administration advantages and challenges of biomolecules
Administration Form Advantages Challenges
Intravenous (IV) • Suitable for substances that may cause irritation
• Large volume administration
• Trained personnel; qualified environment• Port system requirement• Location of peripheral cannula• Time-consuming administration• Risk of systemic infection
Subcutaneous (SQ) • Short clinical visit• Lower resource burden• Less invasive (as compared to IV)• Self-administration possible
• Pain-free administration of larger volumes• Minimization of effects at injection site• Adsorption and bioavailability• Administration of exact dose
Geburtshilfe Frauenheilkd. 2014 Apr; 74(4): 343–349.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4078128/
High Concentration Drivers
High patient doses required for biological products: ~0.1-3mg/kG body weight
Intravenous (IV) infusion most common delivery method due to high administered
doses and low protein concentration
Subcutaneous administration using prefilled syringes preferred by patients
Ease of Use
Fast
Low cost
Dani, 2007
10
Formulation Criteria
Simplicity
Manufacturing-friendly
Robust
Safe (use appropriate excipients)
Meets shelf-life objectives
Satisfy target profile
Meets time-lines
“Informed Compromise”
Rational/Defensible
Reference: “Introduction to the Stabilisation and Formulation of Proteins and Peptides”; Legacy BioDesign, LLC
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
Stability
Conformational
•Native vs. Denatured states
•Chemical Denaturation
•Thermal Denaturation
Colloidal
•Soluble vs. Insoluble proteins
•Distinctly different from aggregation
•Native-state association
Interfacial
•Protein Adsorption
•Binding results in physical instability
•May include interaction with air-water interface
12
Conformational Stability
Stabilizers in solution (i.e. polyols, sugars, etc)
Sugars are also known to stabilize protein conformations against dehydration stresses by substituting surrounding water molecules through hydrogen bonding
Excluded solvent behaviors
13
Sugar/Polyol Initial Concentration Typical Range
Trehalose 0.5 M 0-1.0 M
Mannitol 2% w/v
Sorbitol 0.5 M 0.2-1.0 M
Sucrose 0.5 M 0.2-1.0 M
Amino Acids
Glycine 250 mM 0.25-2.0 M
L-Histidine HCl 20 mM
L-Histidine 20 mM
Lebendiker & Danieli, FEBS Letters 588 (2014) 236–246
Colloidal Stability
Proteins exhibit colloidal properties in solution Attractive or repulsive interactions
Interactions effect solution properties
Solubility, viscosity, and crystallization – can contribute to aggregation
14
Tonicity Agents/Mineral Salts Initial Concentration Typical Range
Sodium Chloride 300 mM 0-1 M
Sodium Sulfate 500 mM 0-0.5 M
Potassium Chloride 200 mM 0-1 M
Ammonium Sulfate 50 mM 0-0.2 M
Amino Acids
L-Arginine HCl 125 mM 0-2 M
L-Arginine 125 mM 0-2 M
Lebendiker & Danieli, FEBS Letters 588 (2014) 236–246
Interfacial Stability
Surfactants
General interaction: Lower the surface tension between two media (liquid/liquid, liquid/solid, liquid/gas)
Non-ionic Detergents
Characterized by non-ionic, hydrophilic headgroups
Limits interaction with ions, hydrophobic environments in solution
15
Surfactant Initial Concentration Typical Range
Polysorbate 20 0.1% 0.01-0.5%
Polysorbate 80 0.1% 0.01-0.5%
Lebendiker & Danieli, FEBS Letters 588 (2014) 236–246
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
17
What are Aggregates?
1. Mahler, H.C.; Jiskoot, W.; “Analysis of Aggregates and Particles in Protein Pharmaceuticals. Hoboken, NJ: John Wiley & Sons, 2012.
• Aggregates are multiple drug molecules held together by covalent bonds or intermolecular forces
• Aggregates larger than pentamers and large particles are of particular interest
• Measurement via multiple methods1
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Therapeutics with high aggregate concentration administered by IV or subcutaneous injection can cause an immune reaction
- Safety Concern – Critical Quality Attribute
- Stresses weakened patient
- Can lead to reduced therapeutic efficacy
Regulatory requirements:
- Testing for visible and subvisible particles
- Maximum specifications
Why are aggregates important?
Rosenberg, A. S. “Effects of Protein Aggregates: An Immunologic Perspective” AAPS Journal 2006, 8 (3).
Carpenter, J. F.; Randolph, T. W.; Jiskoot, W.; Crommelin, D. J.; Middaugh, C. R.; Winter, G.; Fan, Y.-X.; Kirshner, S.; Verthelyi, D.; Kozlowski, S.; Clouse, K. A.; Swann, P. G.; Rosenberg, A.; Cherney, B. “Overlooking Subvisible Particles in Therapeutic Protein Products: Gaps that may Compromise Product Quality” Journal of Pharmaceutical Sciences2009, 98 (4), 1201–1205.
19
Factors Influencing Aggregation
Stresses on protein:
• pH and salt
• Mechanical/Shear
• Raw material quality
Can be improved by selecting the
appropriate excipients, of the appropriate
quality
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
Drug Substance Drug Product
Formulation: Drug Substance + Excipients = Drug Product
Formulation
www.fda.gov
Source of Impurities:
Bulk Drug Substance purification process
Risk-Mitigation Strategies
22
Quality of Raw Materials
• Quality of raw materials can influence protein stability and aggregation
• Stringent quality control can reduce raw material-associated risks
• All specification parameters tested on every raw material batch
• Test methods are thoroughly validated
• Raw material storage stability tested
Impurity Profile• Elemental Impurity Profile is not
required of excipients
• Elemental Impurity Profile is requiredof Drug Product
• ICH Q3D: The applicants risk assessment can be facilitated with information about potential elemental impurities (e.g. by supplier of drug substance and excipients)
• Example shows all 24 elements of ICH Q3D
• Levels above option one limit (calculated to a daily intake of ten gram of drug)
Example: ICH Q3D Elemental Impurity information
23
Example
PDA Formalized Risk Assessment
Excipient Support Documents
• Product quality report [4.1 *]
• Elemental impurity information
• Analytical procedure
In line with CTD chapter 3 quality (adapted for excipients) [2.3*]
• General information
• Manufacture
• Characterization
• Control of drug substance
• Reference standard
• Materials
• Container closure system
• Stability
• Quality Self Assessment [2.6*]
• Audit report summary [2.6*]
• Supply chain Information [2.3*]
• Stability data [2.3*]
[*] No. of supported chapter of Guideline on formalized risk assessment for excipients EU/C 95/210 24
Material qualification
Risk assessmentProcess optimization
Minumum information required to begin material assessment
Support information during Formalized Risk Assessment
Support for Process Optimization and evolving
Regulatory landscape
Formalized Risk Assessment
EU 2015/C 95/02
“… the holder of the manufacturing authorization shall ensure that the excipients
are suitable for use ... by verifying the appropriate GMP…”
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
26
Ultrafiltration & Diafiltration Considerations
Ultrafiltration• IS: Increase in macromolecule concentration
• DOES: Typical concentration increases 5-50x
• MEANS: Anything ≥ MWCO will also increase in concentration
Diafiltration• IS: Exchange of solvent/buffer/excipient conditions
• DOES: Requires 7-10 diavolumes in practice
• MEANS: Anything ≥ MWCO will also increase in concentration
Contaminants such as pyrogens (MW 10kDa-100kDa) can increase in concentration as much as 12-60x in worst case scenario
Retentate
PermeateFeed
Diafiltrate
10/30kDa MWCO
27
Mechanical/Shear Stress
Mechanical/Shear stress can result in largely increased liquid-air interface (bubbles, foam)
Exposure to the liquid-air interface is an aggregation risk for the therapeutic protein!
Stabilizers can protect therapeutic proteins from such stresses in process and final formulated product
Stabilizer options:
Sugars, Polyols and Amino Acids• Conformational stabilizers: Reduce sensitivity to
stress at interfaces by forcing the protein into tight
conformation
Surfactants• Interfacial stabilizers: Reduce stress exposure
of the protein at liquid-air/solid interface
• Almost exclusively applied in the final formulation
due to process challenges
Stirring PumpingShaking
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
Practical Considerations for Bioprocessing Excipients
Process-friendly
Specialized requirements
• Microbial qualification
• Endotoxin qualifcation
• Low levels of contaminants
• Example: Tris, low in polyoxymethylene (POM)
• GMP qualified production
• Example: sodium caprylate
• Paper-free packaging
• Storage stability
• Clumping/flocculant excipients
• Custom packaging
29
Agenda
The Bioprocess Perspective1
Administration & Drivers of Biomolecule Therapeutics2
Functionality of Excipients: Stability3
Aggregation & Contributing Factors4
Sources of Impurities & Risk Mitigation5
Additional Process & Excipient Considerations6
Practical Considerations7
Summary & Discussion8
31
Biologics require special consideration
Biopharmaceuticals• Trend toward higher concentration biologic
therapeutics
• Formulation excipients can prevent protein aggregation, both in the drug product and process
• Excipient grade formulation additives are higher value – rational design of formulations is a must
• Effective chemistries prevent product-product interactions or prevents shear damage
• Trace contaminants such as heavy metals can effect protein stability (elemental impurities)
CLASSIC PERSPECTIVE
32
The Bioprocess Perspective
FORMULATION
PURIFICATION
A DIFFERENT PERSPECTIVE
CONTINUOUS FORMULATION
33