Download Critical Considerations for Analytical Similarity Assessment

Critical Considerations for
Analytical Similarity Assessment
Jennifer Liu
CASSS CMC Strategy Forum Japan 2015
Development of Biosimilars: Technical Aspects
Biologics Are Larger and Structurally More
Complex Than Chemically Synthesized Drugs
Generic
Same Structure
Biosimilars 1.0
Similarity in Structure
2
Biosimilars 2.0
Monoclonal antibodies have multiple biological
functions
EU
Potency
Heavy
chain
ABP
US
Potency Reflective of
Target Binding and
Mechanism of Action
Light
chain
Inter-chain
disulfide
Binding Region for FcRn
(PK)
N-glycan
FcRn
Binding Region for FcR,
Effector Function
(CDC, ADCC)
Intra-chain
disulfide
CDC
ADCC
EU
ABP
US
EU
ABP
US
Biological and functional assays are used to investigate structure/functional
differences which are clinically meaningful for biosimilarity
Biosimilar product development begins with
establishing target quality product profiles
Biosimilar development is reverse
engineering of the reference product
Demonstrate biosimilarity
in a step-wise manner
Define critical quality attributes for the
reference product

Known mechanism of actions, biological functions,
safety, and immunogenicity profiles
Establish product quality profiles based on the
target reference product

Characterize reference product to establish targets
and ranges for critical product quality attributes
Develop biosimilar products to match the
target reference product

Match reference product profiles with greater
emphasis on matching all biological functions
Additional
clinical data
Human
PK and PD
Non-clinical PK/PD and
toxicology as appropriate
Match all predicted functions
and confirm no enhancement of
functions absent
Demonstrate analytical
similarity
Comprehensive analytical similarity is critical
foundation for biosmilarity
Attributes related to the amino acid
sequence and all post-translational
modifications, including glycans
Integrity of the secondary, tertiary,
and quaternary structure
Degradation profiles
denoting stability
Higher
order
structure
Primary
structure
Biological and functional
activities, including receptor binding
and immunochemical properties
Biological
function
Product-related
substances and
impurities
Quantitative levels of
product variants and
their identities
Stability
General
properties
and
excipients
Properties of the finished
drug product, including
strength and formulation
Particles
and
aggregates
Processrelated
impurities
5
Subvisible and submicron particles
and aggregates of various sizes
Impurities from host cells
and downstream process
Similarity assessment may use risk-based tier
approach and statistical analysis
Consider criticality ranking of quality attributes with regard to their potential impact
on activity, PK/PD, and immunogenicity.
Christl, L (FDA CDER) FDA Oncologic Drugs Advisory Committee meeting, 2015
Criticality
Ranking
Statistical
Rigor
High
Low
Tsong, Y (FDA CDER) DIA/FDA Statistics Forum 2015
6
•
Pass equivalence testing if 90% confidence interval of
the true mean difference is within equivalence margins
•
Equivalence margins = 1.50σ where σ is the true
standard deviation of the RP
•
Statistical power (sensitivity to detect difference)
dependent on number of lots
Power
An approach to statistical equivalence testing
for tier 1 attributes
Number of biosimilar batches
McCamish, M. (Sandoz)
Dong, X. (FDA) FDA
This case study is provided for the sole purpose of illustrating FDA’s statistical approach for similarity assessment as presented at FDA ODAC meeting on Jan. 7 2015.
No conclusion of the data is made by the presenter.
Challenges in the tier 1 equivalence approach
• Panel of Tier 1 quality attributes should be consistent for all sponsors seeking
biosimilar product approval to the same original product
• Relationship between quality attributes and safety/efficacy in patients may
not be completely understood
• Specific roles for effector function as part of the clinical mechanism of
action are not entirely clear
• Sufficient number of lots are required for meaningful statistical analysis
• Small number of biosimilar batches reduce statistical power to detect
difference
• Small number of reference product lots can not estimate true variability
• The true variability (standard deviation) in the reference product is difficult to
estimate
• Different reference product lots may come from the same drug substance
lots → underestimating variability
• Differences due to manufacturing process changes → overestimating
variability
Use appropriate characterization techniques in
well-designed analytical studies is critical
Reliability - Methods should be qualified and suitable for intended purposes
Relevance - Methods provide meaningful information and may predict clinical performance
Resolution - Methods should be sensitive and capable of resolving differences
Material age - Attributes impacted by material age should be considered in the assessment
Biosimilar
Reference product
9
Slide from Kozlowski, S (CDER) presentation at 2014 Biomanufacturing Technology Summit, Rockville, MD, June 13, 2014
Understanding the biological relevance of
measured quality attributes is important
Measuring the quality attributes by retaining the important structural characteristics of the attributes
Increase understanding for the biological relevance of different glycan attributes and ensure the critical
attributes are controlled properly in order to match biological functions
Confidence in similarity
A2G0F
Critical
Glycans
Oligosaccharide Analysis (Glycan Map)
30.0
(e.g. high-Man)
A2G2F
M7
A2G1F(a)
A2G1F(b)
M6
A1G1F
10.0
M5
A1G0F
A2G0
20.0
min
0.0
Relevance
4.0
Glycan
Map
profile
6.0
8.0
10.0
12.0
14.0
16.0
18.0
20.0
Monosaccharide Analysis
Monosaccharide
analysis
Reliability
10
22.0
24.0
26.0
Knowing the correlation of orthogonal methods
helps develop a robust control strategy
ADCC vs. Afucosylated glycan
Orthogonal assays with increasing
biological relevance to discern
clinically meaningful differences
and confirm functional similarity
Confidence in manufacturing
Chung, mAbs, 326-340, May 2012
NK92
ADCC
High resolution and reliable methods
suited for process control can guide the
process and product development.
Response (LU))
20.0
10.0
0.0
4.0
Reliability
11
A2G2F
M7
30.0
A2G1F(a)
A2G1F(b)
M6
A2G0F
Glycan
map
M5
A1G1F
Relevance
FcgRIIIa
binding
A1G0F
A2G0
PBMC
ADCC
min
6.0
8.0
10.0
12.0
14.0
16.0
18.0
20.0
22.0
24.0
26.0
Critical glycan attributes are modality and
molecule dependent
A2G0F
Biosimilar epoetins: how similar are they?
30.0
Isoform
10
11
12
13
14
A2G2F
M7
10.0
M5
A1G1F
A2G1F(a)
A2G1F(b)
M6
A1G0F
A2G0
20.0
min
0.0
[U/mg]
RP
4.0
RP
In Vivo Bioactivity
400000
350000
300000
250000
200000
150000
100000
50000
0
5
7
8
9
10
11
Isoform Number
Schellekens H. Eur J Hosp Pharm Sci. 2004;3:43–47.
12
13
14
6.0
8.0
10.0 12.0 14.0 16.0 18.0 20.0
Sensitivity to
difference
Impact to
epoetins
Glycan Type
Impact to
mAb
Sensitivity to
difference
High
Increase
clearance
No glycan
No ADCC
Low to medium
Low to medium
Increase
clearance
Bisecting GN
Increase ADCC
Low to medium
Medium
Increase
clearance
High mannose
and ADCC
Medium
High
Increase
clearance
Terminal Gal
Increase CDC
Low
High
Decrease
clearance
Sialic acid
Antiinflammatory
and ADCC
Low
12
N/A
N/A
Afucosylated
Increase ADCC
High
Fingerprint-like similarity versus
Fingerprint-like methods
FDA Definition of Fingerprint-like:
a term to describe integrated, multi-parameter approaches that are extremely sensitive in
identifying analytical differences.
FDA DRAFT GUIDANCE
“Clinical Pharmacology Data to Support a Demonstration of Biosimilarity to a Reference Product”
Koslowski, presentation at CASSS WCBP Conference, Washington DC, Jan, 31 2013
13
Analytical methods which may provide
fingerprint-like profiles
• Methods investigate the overall conformational integrity
•
•
•
•
•
1-D NMR
2-D NMR
Crystallography
Antibody conformation array
H/D exchange
• Methods investigate the heterogeneous characteristics
• Peptide map
• Glycan map
Can any one of these methods provide prove fingerprint-like similarity in its own right?
14
1H
NMR provides fingerprint pattern
•
Applications for monoclonal antibodies and less complex proteins have been shown
•
Visual profile comparison could be subjective. An objective comparison for
spectrum similarity would require complex mathematical algorithm
V. Visser et. al, BioDrugs, 07 May 2013
L. Poppe, Anal. Chem. 2013, 85, 9623-9629
Similarity is assessed based on pattern similarity and little information can be discerned on the
differences and their impact to purity, safety, and efficacy
15
2D-NMR has been applied for smaller nonglycosylated protein
•
Several publications on filgrastim (small non-glycosylated protein of ~ 19,000
Dalton) 1H-15N 2D-NMR spectral (pattern) similarity
•
Provides higher resolution in structural information compared to 1D-NMR down to
the single amino acid level
M. Levy, Anal. Bioanal. Chem. 22 Nov 2013
R. Brinson, AAPS, 2013
D. Hodgson, WCBP, 2012
Sandoz presentation to ODAC, 07 Jan. 2015
May not be suitable for glycoprotein and monoclonal antibodies which is structurally more
complex than filgrastim
16
Crystallography has been applied to
investigate sub-domains of large proteins
•
Typically require changing formulation to allow crystallization of protein of subdomains of mAb
•
Crystallization process generally serves as a purification step selecting the most
“homogeneous” population, and could miss low abundant sub-populations
S. K. Jung, mAbs 6:5, 1163--1177; September/October 2014
V. Visser et. al, BioDrugs, 07 May 2013
Does not investigate heterogeneous populations or discern sub-populations which may have
different biological activities
17
H/D Exchange provides site-specific
information on structural differences
• H/D exchange require long experimental time with multiple testing time points.
• Investigate differences in the exchange rate comparing two products under the same
condition. Results could be informative in regards to detailed structural differences at
specific locations
Z. Zhang Anal. Chem. 2012, 84, 4942−4949
Interpretation of complex results requires experienced subject matter experts
18
Antibody conformation array could identify
new epitopes due to changes in conformation
•
Evidences of regional conformational change may predict impact to biological
activities mediated through specific antigen or receptor recognition
•
Reagents maybe high cost and experiment is relatively low throughput
S. K. Jung, mAbs 6:5, 1163--1177;
September/October 2014
X. Wang, CHI’s 6th Annual Biotherapeutics Analytical Summit
Comparability for Biologics & Biosimilars March 13, 2015
Orthogonal to biological assays in investigating structure/functional differences
19
Capabilities and gaps of these fingerprint-like
methods
Technique
Capabilities
Gaps
1D-[1H]-NMR
Sensitive to detect differences for both
small and large proteins including
monoclonal antibodies
Difficult to interpret results and primarily
rely on pattern similarity.
May not determine specific site and levels
of differences
2D-[1H-15N] HSQC
NMR
Sensitive to detecting differences down to
amino acid levels for small proteins
May not be suitable for complex biologics,
such as glycoprotein and monoclonal
antibodies
X-ray crystallography
Primary application for smaller protein or
fragments of monoclonal antibody.
Assess sub-populations which are
homogenous in nature
Limited resolution to structural
differences for large protein.
May omit minor components with
unknown safety or efficacy impact.
H/D exchange
Provide detailed structural differences at
specific locations
Long experimental time. Interpretation of
complex results requires experienced
subject matter experts
Ab conformational
array
Data analysis is less complex compared to
the other fingerprinting methods.
Provides regional structural information
Require product-specific reagents which
could be costly or may not be available
These methods might provide a partial 'fingerprint' of higher order structure
but are not sufficient to demonstrate 'fingerprint-like similarity’.
20
Summary
• Comprehensive and well-designed similarity assessment is the
foundation for biosimilarity
• US FDA recommends risk-based approach for tier assignment and
statistical analyses
• Challenges associated with the current approach require further
guidance
• Biosimilar product need to demonstrate similar functions using biological
assays relevant to potential clinical mechanism of action
• There is no one method alone capable of indicating “fingerprint-like
similarity”; it requires a collection of methods, including bioactivity
assays.
• “Fingerprint similarity” presumably is matching all
structural/functional assessments while using comprehensive
sensitive methods
21
Acknowledgements
Simon Hotchin
Leszek Poppe
Margaret Karow
Pavel Bondarenko
Sundar Ramanan
Zhongqi Zhang
Richard Markus
John Gabrielson
Gino Grampp
Brad Jordan
Izydor Apostol
Linda Narhi
22