Edward Narke discussed the CMC pathway for biologics through clinical development and market approval. The goals are to better understand FDA requirements, visualize a cost-effective approach to manage manufacturing processes, and appreciate challenges in controlling safety, potency, and impurities. Biologics have complex structures that must be characterized and controlled. Assay methods, product specifications, stability data, and comparability between clinical and commercial materials are common reasons INDs are placed on clinical hold. Managing impurities, developing relevant potency assays, and collecting data continuously are important strategies to address these challenges over the course of development.

1. Edward Narke
Regulatory Managing Director
DS InPharmatics
Journey in the Development of Biologics
Through End of Phase 3
The CMC Pathway

2. The CMC Journey in the
Regulation of Biologics
Our Goals
• To better understand the FDA’s CMC requirements and
expectations for biologic manufacturing and product
testing
• To better visualize a cost-effective, risk-managed
approach to manage these manufacturing processes and
products through clinical development into market
approval
• To better appreciate the challenges involved with
controlling safety, potency, and impurity profiles for these
products

3. Process Overview of Biologics
Virus inactivation
Virus removal
Harvest
FiltrationFiltration
Chromatography
column (Size Exclusion) Chromatography column
(Ion Exchange)
Chromatography
column (HIC)
WCB
Bioreactor (fermentation)
Filtration
Sterile fill
lyophylization

4. What makes Biologics Special?
Biologics have Expected
• Primary, secondary, tertiary,
quaternary structure
• Size
• Charge
• Hydrophobicity
• Folding (S-S bonds)
• Glycosylation
• Bioactivity
• Heterogeneity
& Unwanted:
• Aggregation
• Incorrect folding
• Truncation
• Amino acid modifications oxidation, deamidation,
glycation, etc.

5. A Big Picture Approach is Desirable
Pre-clinical
Phase 1
Phase 2
Phase 3
Phase Development
Not So Obvious
How much test method
validation, product
characterization, stability? How
tight should specs be? Do I need
a bioassay?
Unambiguous Requirements
Validated Test Methods
Complete Product Characterization
Final Specifications
Expiry Date Assigned
Bioassay Related to Function
Full Change Control Program

6. Question?
• What are some critical items to open an
IND and most common reasons why
INDs get placed on Clinical Hold, and
how to avoid this.

7. Product Characterization?
• Inadequate characterization data provided
– Identity*, heterogeneity/variants (size, charge, hydrophobicity,
glycosylation), aggregates, etc.
– Process-related impurities (HCPs, DNA, antibiotics, chemicals)
• Specifications inadequate to control quality
– Inadequate spectrum of release tests
– Acceptance criteria too wide
• What to do?
– Evaluate product as much as feasible before starting
nonclinical and clinical studies

8. Methods for Product
Release
• Assay Methods not suitable for
intended purpose
– SEC for Aggregates
– Potency Assay

9. BioActivity Assays?
• Absence of bioactivity/or Potency assay
specification
– Critical quality attribute for proteins
– Proteins inactivated by various conditions
– Potency assay required to evaluate and control product
quality
– Inability to assure consistent dosing of product between
lots; safe dose
• What to do?
– Develop and implement a relevant & quantitative
bioactivity and or potency assay and set a
meaningful specification

10. Viral Safety?
– Cell banks or animal-derived raw materials
not appropriately tested for endogenous or
adventitious agents (mostly viruses,
retroviruses)
– Manufacturing scheme not validated for its
ability to remove or inactivate retroviruses
• Transmission of infectious viruses to humans
• No information on country of origin of ruminant
derived materials used in manufacturing
– Concern over TSEs; BSE

11. Viral Safety?
– What to do?
Retroviruses
• Estimate retrovirus particle load in cells &
unpurified bulk; potential particles/product dose
• Document ability of process to adequately remove
retroviruses
Exogenous viruses
• Evaluate potential presence of viruses
• Include 2 robust, orthogonal viral reduction steps

12. Pharmaceutical Process-Related
Impurities Major Safety Concern for
the FDA!
The FDA can place your clinical study in
‘clinical hold’ for the following CMC reason:
MAPP 6030.1 – “if there are any reasons to
believe the manufacturing or controls for the
clinical trial product present unreasonable health
risks to the subjects … such as a product with
an impurity profile indicative of a potential health
hazard or an impurity profile insufficiently
defined to assess a potential health hazard”

13. Impurity Safety Assessment For
Biologics Product-Related Impurities
 Protein Aggregation
Known immunogenecity
 Amino Acid Changes
Immunogenecity (e.g., oxidation of methionine)
 Glycosylation Changes
immunogenecity

14. FDA Guidance For Industry CMC IND
Content For Phase 2 and 3 1999
“Impurities should be identified, qualified, and
quantified, as appropriate. Suitable limits
based on manufacturing experience should
be established.”
“For peptides and proteins,
characterization should include data on the
amino acid sequence, peptide map, post-
transitional modifications (e.g., glycosylation,
gamma carboxylation), and secondary and
tertiary structure information, if known.”

15. Design of the Manufacturing
Process!
“The extent of purification of recombinant DNA products
should be consistent with the intended use of the product.
Drugs and biologics which are to be administered
repeatedly or at high concentrations should be adequately
pure to prevent the development of undesired immune or
toxic reaction to contaminants.
The purification process should be designed to specifically
eliminate detectable viruses, microbial and nucleic acid
contamination and undesirable antigenic materials.”
1985 FDA Guidance: Production and Testing
of Recombinant DNA-derived Products

16. List All Actual/Potential Impurities!
• Process-related impurities
 Cell-substrate (DNA, HCP, proteases, endotoxins)
 Cell-culture (cell-substrate [DNA, HCP, protease];
endotoxin; media components – antibiotics [tetracycline,
gentamicin], hormones [insulin, IGF-1, transferrin],
serum)
 Purification (enzymes [DNase/RNase]; resin leachates;
surfactants; residual cleaning agents]
Product-related impurities
FDA Guidance for Review Staff and Sponsors: Gene Therapy 2004

17. Identify the “Critical Impurities”!
‘Critical Impurity’: That which must be
controlled to a defined level to assure
appropriate quality and/or safety!
 Impurity that impacts patient safety risk
 Impurity that is difficult to consistently remove
 Impurity that varies from batch-to-batch or
changes with time
 (case by case)

18. Risk Management of Impurities
Goal: Determine how you will demonstrate to
regulatory agencies adequate control of the specified
impurities!
Impurity Control Mechanisms
 Process validation
 In-process action limit monitoring
 End product specification release/stability testing
 Combination of above

19. Determine Acceptance Limits
What to Base Acceptance Limits On
• Known toxicity information
• Required regulatory targets/specs
• Levels consistent with clinical materials
• Company-specific requirements

20. Specifications: Early
Development
• Acceptance Criteria Generally Broad (Focus on
Safety/Efficacy)
– Define safety limits, where possible, with regulatory
guidance
– Example: LAL ≤5 EU/kg/dose
– Tighten specifications as manufacturing experience
increases
• Employ Quantitative Methods Where Feasible
• Push the Envelope With Toxicity Studies to
Underwrite Safety
• Understand the Impact of Process Changes on
Product Quality

21. Specifications Through
Development
• Specifications Are Expected to Change
– Changes to Analytical Methods
– Evaluation of Stability Data
– Changes to Formulation
– Process Changes and Process Capability
– Enhanced Understanding (Characterization)
– Increased Manufacturing Experience
– Process Validation and Clearance Studies

22. Specifications Through
Development
While acceptance criteria generally get tighter with
increased manufacturing experience, there may be
some cases where widening the criteria may be
acceptable.
• Analytical Testing May Decrease for Late Phase
Products
– May remove tests following process validation/clearance
• Examples: Viral Testing and DNA
– May remove tests based on process consistency
• Examples may include monitoring of oxidation/acidic variants

23. Specifications: Late
Development
• In General, Expect to Tighten Specifications
– Methods Are Fully Validated and Locked Down
– Extensive Manufacturing Experience
– Link Between Product Quality & Clinical Outcome
– Statistically Relevant Pool of Data
– Enhanced Understanding of Product Stability
• Internal Targets
– Reflect Process Capability
– Product quality may still be high outside of internal targets
• Make Specifications Relevant

24. Designing Relevant
Specifications
• The Good
– Supported by appropriate, well designed analytical methods
– Address all the quality attributes that impact safety and efficacy
– Underwrite safety and efficacy through end of shelf life
– Reflect a thorough understanding of the molecule and the process
• The Bad
– Analytical methods inappropriate, poorly validated, lacking specificity
– Contain tests that are irrelevant to product quality–Lack tests for
critical quality attributes due to poor characterization
– Lack relevance to clinical experience
– Driven by analytical or process capability
– Contain tests performed “because we can”

25. The Perfect Process
Early Phase Development
• Phase 1 Study with Pilot-Scale Material: Process Not Optimized
• Acceptance Criteria for Clips/Truncations Very Wide
• Process May Not Optimized for Removal of Aggregates
• No Assay for Acidic Species or Oxidation
• Clinical Data Shows Good Safety and Efficacy
Later Phase Development
• Methods Optimized: More Sensitive and Quantitative
• Clinical Samples Re-evaluated With Optimized, Quantitative Methods
• More Results Define Further Knowledge
• Specifications Based on Process Capabilities and Relevant Clinical
Experience
• Targets Set on Patient Safety Considerations and Process Capabilities
– Plan Ahead –Understanding of process capability will increase over time as you
gain experience.

26. A Few Key Questions
• What are some of the major challenges
that are faced in meeting CMC filing
requirements?
• What are the some strategies that are
applied to address the major challenges?

27. Assay Methods for Product
Release?
• Assay methods not suitable for intended
purpose
Examples:
– SEC for aggregates: Sample treated to
reduce aggregates before running column
– SDS-PAGE gels under-loaded
– Potency assay: “what is active”

28. COMPARISON OF NONCLINICAL
& CLINICAL LOTS?
– Product used in animal toxicology studies not
comparable to product intended for clinical
• Can’t rely on Tox studies establishing safety
(special emphasis on impurities, degradants,
aggregates)
– What to do?
• Do key Tox studies on appropriate material;
• Do side-by-side comparisons of non-clinical and
clinical lots
• Evaluate potential safety impact of differences
between Tox and clinical lots

29. Stability Testing?
– No stability data or testing plan
• Product stable throughout nonclinical studies
• Product will be stable for duration of clinical studies
– Stable under conditions of use (diluted, etc.)
• Product changes that would result in safety risk
– e.g., release of untargeted toxin
– e.g., release of radiolabel
– e.g., aggregation
– e.g., loss of sterility

30. Insufficient Information
Submitted?
– Clinical trial material not yet manufactured
• No release or characterization data on the actual
product to be administered to patients
• Uncertain that product suitable for clinical use
– Problem exacerbated by limited set of
specifications and wide acceptance criteria;
limited understanding of critical product
characteristics
– What to do?
• Manufacture clinical lots, provide release data
before submitting IND

31. Collecting the Data as the
Journey Continues
Key question: How and when to invest to really get to know the
manufacturing process and its outcome
Marginal conditions: Seek out regulatory authority advice. It’s all about
involving the agency as a partner
Milestones: A reality check for your CMC regulatory approach at any
transition

32. What Is ‘Potency’?
‘Potency’ = the assessment of
‘biological activity’
Impacted by both molecular
conformation and by molecular variants!

33. Potency is Invaluable in Biologic
Manufacturing!
• Parameter of product quality release testing
(‘active content’)
• Tool for assessing lot-by-lot manufacturing
consistency during normal manufacturing
operations
• Tool for assessing product stability
• Tool for demonstrating product comparability
after a manufacturing process change

34. BioAssays/Potency: Required
Measurement for Biologics
• 21 CFR 610.10
“Tests for potency shall consist of either in vitro or in vivo
tests, or both, which have been specifically designed for
each product so as to indicate its potency in a manner
adequate to satisfy the interpretation of potency given by
the definition in 600.3(s)”
 21 CFR 600.3(s)
“The word potency is interpreted to mean the specific ability
or capability of the product, as indicated by appropriate
laboratory tests or by adequately controlled clinical data
obtained through the administration of the product in a
manner intended, to effect a given result”

35. Regulatory Expectations For the
Choice of Bioassay/Potency
“ A correlation between the expected clinical
response and the activity in the biological assay
should be established in pharmacodynamic
or clinical studies.”
ICH Q6B Specifications for Biologics

36. When Must a
Biologic/Biopharmaceutical Have a
Potency Bioassay?
“Potency assay (i.e., ability to induce immune
response such as proliferation of responder
cells, cytotoxicity or any other correlation with
biological activity) is to be in place at Phase
1/2, and established at Phase 3”
Regulatory Expectations During Product Development for
Tumor Vaccines, Raj Puri, FDA

37. What About Setting Potency
Specifications?
Regulatory guidance on setting potency
specs
- limited! (as with other specifications)
“The permissible range of values in potency assays that reflects
adequate biological activity of a product should be based on
experience……”
FDA PTC MAbs 1997

38. Development Phases
Controlling Quality
and Basis for QTPP?
• Do I have a reliable process that
is reproducible?
• Do I have a reliable, specific and
sensitive analytical method?
• What are the physical chemical
properties? Can it be readily
formulated-delivered and
maintain stability?
Pre-IND
Initiating Phase 1
Early Clin Dev
Transition Ph2 to
Ph3
POC to Registration
Continuous Improve
Key Questions
Conditions/Features
Basis/Considerations
Milestone/Result -
Further Actions

39. Development Phases
Basis for QTPP?
• How do I want to (need to)
deliver the drug?
• What, if any, are the key
properties of the drug that could
confound clinical results?
• Can I produce a compliant and
convincing CMC package?
Pre-IND
Initiating Phase 1
Early Clin Dev
Transition Ph2 to
Ph3
POC to Registration
Continuous Improve
Key Questions
Conditions/Features
Basis/Considerations
Milestone/Result -
Further Actions

40. Example of Release Specifications For
a Marketed Biologic

41. Implications of New
Regulations?
• What about Refuse to File
• Actions for BLAs

42. Refusal to File BLA for
Protein Product?
• Facility not ready for inspection during the
time frame of the review clock
• Lack of process validation
• No stability data on product intended for
commercial use

43. Summary?
• Implications of Regulations?
• Principles for selecting effective
development and regulatory CMC
strategies in an evolving regulatory
environment?
• How Much Information?
• What is the best way to use opportunities
to consult with the Agency?

44. What you don’t know can
hurt you….
• “…there are known
knowns; there are
things we know we
know. We also know
there are known
unknowns; that is to
say, we know there
are some things we
do not know. But
there are also
unknown unknowns –
the ones we don’t
know we don’t know.”

45. Thank you …