Selecting Quality Parameters for Setting Specifications

1
Selecting Quality Parameters for Setting
Specifications

• Wassim Nashabeh
• Director, QC Clinical Development
• Genentech, Inc.

2
Scope of Specifications

• Specifications are one part of a total control
  strategy designed to ensure product quality and
  consistency
• 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
• How to select those characteristics?

3
Critical Product Quality Attributes

• Appearance/Description
• Identity
• Purity/Impurity
• Product-related
• Process-related
• Potency
• Quantity
• General Tests pH, osmolality, critical
  excipients,particulates, moisture, volume in
  container and content uniformity
• Contaminants LAL, Bioburden, sterility

4
Selection of Quality Attributes Purity/Impurity
(ICH Q6B)

• Product-related Substances
• Molecular variants of the desired product formed
  during manufacture and/or storage which are
  active and have no deleterious effect on the
  safety and efficacy of the drug product
• Product-related Impurities
• Molecular variants of the desired product
  (precursors, certain degradation products arising
  during manufacture or storage) which do not have
  properties comparable to the desired product with
  respect to activity, safety and efficacy
• Process-related Impurities
• Derived from the manufacturing process and are
  classified into three major categories
  cell-substrate derived, cell-culture derived and
  downstream-derived

5
Selection of Quality Attributes Product-related
Variants (ICH Q6B)

• Physicochemical and Biological Characterization
• Develops an understanding and definition of the
  product heterogeneity and degradation profile
  including
• the type of chemical or enzymatic modification
• site of modification (amino acid residues
  involved)
• preferred analysis method(s)
• Defines the desired product and a list of all
  product related variants
• Need to classify variants as either
  product-related substances or impurities

6
Selection of Quality Attributes Process-related
Impurities

• Process characterization,validation and
  qualification
• Define process capability and natural variability
• Define critical process parameter and acceptable
  ranges
• Confirm process performance and reproducibility
• Validates the ability of the process to
  consistently remove process and certain product
  related impurities to acceptable ranges
• The design and results of these studies are
  critical in determining the need for routine
  testing for selected process/product-related
  impurities

7
Selection of Quality Attributes Analytical
Methods

• The choice and optimization of analytical
  procedures for specifications should focus on the
  separation of the desired product from
  product-related substances and from impurities
• Measures critical and clearly defined product
  attributes
• Purpose/Type
• Deliverable (What and How) as it relates to
  acceptance criteria
• Quality attributes should be assessed with a
  combination of relevant orthogonal analytical
  methods

8
Criteria to Setting Acceptable Ranges for Product
Release Specifications

• The acceptance criteria (range) established for
  Product Release Specifications should at a
  minimum encompass the process capability limit,
  i.e., the typical variability observed in product
  quality attributes using a controlled and stable
  manufacturing process
• Understanding of key variables is essential in
  establishing the correlation between product
  quality attributes and process capability

9
Criteria to Setting Acceptable Ranges for Product
Release Specifications Challenges

• Clinical experience is gathered throughout
  clinical trials Phase I-III using material likely
  produced with different or evolving processes
• Process consistency/capability is typically
  demonstrated using the final market manufacturing
  process (Phase III and Qual lots), where clinical
  exposure likely derived from Phase III material
  only
• Phase III manufacturing typically done at full
  scale with a single campaign

10
Criteria to Setting Acceptable Ranges for Product
Release Specifications Challenges

• Assuming no significant changes in manufacturing
  process (with direct product quality impact)
  occur throughout clinical development, and
  normal distribution of the data, the greater the
  n of small scale production of Phase I/II lots,
  the more certainty we have that the distribution
  of the data represents the true distribution of
  variability
• Standard error is proportional to 1/vn

11
Criteria to Setting Acceptable Ranges for Product
Release Specifications Challenges

• Early clinical production should not be driven
  only by clinical trials material need, but also
  to better understand the likely product quality
  variables
• To capture both within-campaign and
  between-campaign variability, where different
  lots of key raw materials are likely to be used
• To provide lots for clinical evaluation that
  include product variants representative of the
  full specification range of what will be
  eventually proposed for licensure

12
Criteria to Setting Acceptable Ranges for Product
Shelf-life Specifications

• The acceptance criteria (range) established for
  Product shelf-life Specifications should at a
  minimum encompass changes observed in product
  stability/heterogeneity profile under storage,
  handling, shipping and allowable excursions up to
  expiry dating of the product. The changes should
  be incorporated in addition to the release
  acceptance criteria ranges.
• Use of properly aged material in clinical trials
  is important in establishing shelf-life specs

13
Initial Specifications at Time of Licensure
Projected Process Capability
Clinical Range
Specification
14
Specifications after Significant Manufacturing
History
Proven Process Capability
Clinical Range
Specification
15
Case Study Selection of Quality Parameters of a
recombinant Monoclonal Antibody(rMAb)

• Look for any safety, efficacy, immunogenicity and
  PK/PD signals in pre-clinical and clinical
  studies
• Detailed understanding of all variants present
  derived from extensive chemical characterization
• A relevant set of biological assays to
  characterize the potency test used for release
  and assess activity of product variants
• Studies to assess product stability profile under
  storage, handling, shipping and allowable
  excursions
• Relevance of observed changes to product
  heterogeneity profile
• Relevance of observed changes to product safety
  and efficay

16
Case Study Selection of Quality Parameters of a
recombinant Monoclonal Antibody(rMAb)

• Understanding the correlation between product
  quality attributes and process capability
• Expected variability in product heterogeneity
  profile at process capability limit
• Understanding true variables (Raw materials,
  intra and inter campaign variability, operational
  parameters, instrumentation)
• Correlation between expected product-related
  variants/process-related impurities ranges and
  clinical/non-clinical relevance
• Should be assessed early in clinical development
  in conjunction with clinical and non-clinical
  teams
• Critical attributes should be characterized in
  non-clinical or clinical model

17
Case Study Selection of Quality Parameters of a
recombinant Monoclonal Antibody(rMAb)

• Physicochemical Characterization
• Structural Characterization/Confirmation (Desired
  Product)
• Amino acid composition
• N-and C-terminal sequence analysis
• Peptide mapping
• Disulfide bridges/free sulfhydryl analysis
• Carbohydrate structure
• Monosaccharide composition
• Oligosaccharide profile
• Glycosylation occupancy
• Glycation
• Physicochemical properties
• Molecular weight or size
• Isoform pattern
• Extinction Coefficient

18
Case Study Selection of Quality Parameters of a
recombinant Monoclonal Antibody(rMAb)

• Heterogeneity Profile
• Size based
• Native Size exclusion Chromatography
• Denatured CE-SDS/SDS-PAGE (reduced, non-reduced)
• Charge based
• Ion-exchange chromatography
• Capillary isoelectric focusing/IEF gel
• Capillary Zone electrphoresis
• Hydrophobicity based
• Reversed-phase chromatography
• Hydrophobic interaction chromatography

19
Case Study Selection of Quality Parameters of a
recombinant Monoclonal Antibody(rMAb)

• Biological/Immunochemical Characterization
• describe the molecules relevant therapeutic
  activity
• assess impact of product-related variants on
  activity
• support rationale for selection of lot release
  potency assay
• Tools
• F(ab) related assays
• Affinity functions ELISA, BIACORE, FACS
• F(c) effector function assays
• C1q, Fc(g) receptor family, CDC, ADCC
• Molecule Specific Activity assays

20
Case Study Fc Glycosylation in rMAb--Should it
be specified?
Fuc Gal - GlcNAc - Man
Man - GlcNAc - GlcNAc - Asn297 Gal - GlcNAc - Man

Variability due to terminal Gal core
Fuc oligomannose vs. biantennary non-glycosy
lated Impacts on complement-dependent
cytotoxicity antibody-dependent
cytotoxicity antigen binding pharmacokinetics
21
Case Study Impact of Fc Oligosaccharides on
Clearance of rMAb1 Study Design

• Non-clinical and clinical pharmacokinetics
  studies to assess relevance of selected variants
  (Fc Glycosylation)
• Mouse model
• - three rMAb production lots
• - IV administration at 5 mg per kg body mass
• - take serum samples at 15 min, 6 hr, 24 hr, 4
  days post-dose
• Recover rMAB from serum for glycosylation
  analysis
• - anti-kappa affinity RP columns to purify
  antibody
• - MALDI-TOF/MS analysis of the glycopeptide
• Key assumption
• - oligosaccharides that mediate accelerated
  clearance will be
• reduced over the course of clearance

22
Glycopeptide MALDI-TOF/MS
80
15 Minutes
70
6 Hours
24 Hours
60
4 Days
50
Percent peak area
40
30
20
10
0
Man5
G0-Glc
G0-Fuc
G0
G1
G2
No change in oligosaccharide distribution over
the course of clearance Given other factors in
decision tree, glycosylation is not specified
23
Conclusions

• Selection of Quality Parameters to specify should
  be derived from a thorough understanding of the
  product non-clinical, clinical and CMC attributes
• A risk based approach should be utilized in the
  selection of parameters and associated acceptance
  criteria
• The design of the required studies should be
  considered early in the clinical development
  cycle
• Overall Quality assessment should be performed
  with a combination of relevant orthogonal
  analytical and biological methods

24
Acknowledgements

• Tim Gregory
• David Giltinan
• Mary Sliwkowski
• Reed Harris