Antibody arrays to measure biosimilar mAb comparability at molecular level.

2. YOUR PATH TO SUCCESS
Antibody Arrays for Biosimilar Conformational
Comparability Analysis

3. 3-D Conformational comparability Analysis
Process-related Impurity Analysis
Array Bridge provides ELISA based analysis for Host Cell a homologous counterpart in the human body, these
Proteins from CHO (Chinese Hamster Ovary ) and E. coli antibodies could interfere with the physiological function
host. The development and production of the ELISA kits of the protein through cross-reactivity. Thirdly, HCPs
are under cGMP to ensure uninterrupted product supply themselves could act as agonist or antagonist to interfere
and consistent quality. Host Cell Proteins are proteins and with the human normal metabolism. Because of these
their derivatives from the hosts used for biologics reasons, in biologics development, significant resource is
development and production. Higher levels of HCP will allocated during process development to reduce HCP
pose risks in several areas. levels in the biologics product.
First, HCPs from CHO and E. coli could be recognized by
the human immune system as no self molecules, eliciting
an immune reaction. Depending on the level and composi-
tion of the HCPs, the reaction could range from none and
mild reaction to severe reactions. Secondly, some HCPs
could induce the production of antibodies. If the HCP has

4. Protein Conformational Arrays, a new
approach for biologics three–dimensional
structure comparability analysis
Protein Conformational Array ELISA provides a The FDA guidance
systematic, sensitive and robust comparability testing further stated that
for biologics (therapeutic proteins) at molecular level. “The three dimensional
An array of polyclonal antibodies was designed systemati- conformation of a
cally covering the whole biologics sequence and the assay protein is an important
is in an easy-to-use ELISA format, these Protein Confor- factor in its biological
mational Array ELISAs (PCA ELISA) can provide valuable function. Protein
information on the 3-D structure and heterogeneity of generally exhibit
biologics, and can be used at many stages and aspects complex three-dimen-
of biologics development including cell line selection, sional conformations
process development, formulation development and (tertiary structure
product release testing. and, in some cases,
quaternary structure) due to their large size and the
It is known that the clinical and biological properties of a rotational characteristics of protein alpha carbons.
biologics are the results of their basic properties such as The resulting flexibility enables dynamic, but subtle,
amino acid sequence and three-dimensional structure, as changes in protein conformation over time, some of which
well as the production, purification, formulation and storage may be absolutely required for functional activity.”
conditions. One of the major challenges in biologics develop- “... at the same time, a protein’s three-dimensional
ment is protein immunogenicity, unwanted immunogenicity conformation can often be difficult to define precisely
could lead to reduced or loss of drug efficacy, altered using current physiochemical analytical technology.”
pharmacokinetics (PK), general immune and hypersensitivity
reaction, and neutralization of the natural counterpart in Because of the close relation between protein conforma-
the human body. Multiple studies have demonstrated that tion and its immunogenicity, several analytical techniques
protein conformation stability is closely related to its and bioassays have been used to probe conformational
immunogenicity. One recent study indicated that a protein comparability in biologics. For example, protein intrinsic
has a threshold of conformational stability to prevent the fluorescence, analytical ultracentrifugation, gel filtration,
immunogenicity of foreign proteins. Another strong indica- light scattering and bioassays have all been employed for
tion that protein conformation is closely related to its protein conformational analysis. However these approach-
immunogenicity is through the study of protein aggregation. es have their respective limitations, generally they lack
Multiple studies showed that protein aggregation is a major the desired sensitivity, coverage and throughput to
source of immunogenicity. provide the information about protein 3-D structure.
In the case of monoclonal antibody biologics, Bioassays
In the recently published document for biosimilar developed based on target-antibody recognition will
development by the Food and Drug Administration detect some changes in the CDR (complementarity
(Guidance for Industry, Quality Considerations in determining region) regions, but can’t measure changes
Demonstrating Biosimilarity to a Reference Protein in the rest of the biologics molecule.
Product, FDA, February 2012), FDA recommends
“Extensive, robust comparative physicochemical and The Protein Conformational Array developed specifically
functional studies should be performed to evaluate toward monoclonal antibody drugs could provide a
whether the proposed biosimilar product and the sensitive, systematic and efficient way to measure protein
reference product are highly similar. A meaningful conformational comparability. The protein conformational
assessment as to whether the proposed biosimilar array antibodies are developed from the specific sequence
product is highly similar to the reference product of each monoclonal antibody drug; about 30 different
depends on, among other things, the capabilities of antibodies were developed to provide a systematic
available state-of-the-art analytical assays to coverage of the molecule. Studies using marketed
assess, for example, the molecular weight of the monoclonal antibody drugs indicated that these confor-
protein, complexity of the protein (higher order mational arrays can provide detailed information about
structure and post-translational modification), degree the molecule and detect changes that may not be detected
of heterogeneity, functional properties, impurity by the aforementioned techniques including bioassays.
profile, and the degradation profiles denoting stability.”

5. Application — 1
Comparison between marketed monoclonal
antibody drug and biosimilar candidate.
Comparison of Three Lots of Innovator Molecule and a Biosimilar Candidate
2.5
2
OD 450 nm
1.5
1
0.5
0
Ab1
Ab2
Ab3
Ab4
Ab5
Ab6
Ab7
Ab8
Ab9
Ab10
Ab11
Ab12
Ab13
Ab14
Ab15
Ab16
Ab17
Ab18
Ab19
Ab20
Ab21
Ab22
Ab23
Ab24
Ab25
Ab26
Ab27
Ab28
Ab29
Ab30
Reference Lot 1 Reference Lot 2 Reference Lot 3 Biosimilar
Application 2
Formulation development
Application of Conformational Array to Formulation Development
2.5
2
OD 450 nm
1.5
1
0.5
0
Ab1
Ab2
Ab3
Ab4
Ab5
Ab6
Ab7
Ab8
Ab9
Ab10
Ab11
Ab12
Ab13
Ab14
Ab15
Ab16
Ab17
Ab18
Ab19
Ab20
Ab21
Ab22
Ab23
Ab24
Ab25
Ab26
Ab27
Ab28
Ab29
Ab30
Control Pi Buffer, O ion Pi Buffer+400mM NaCL Histidine Buffer

6. About Array Bridge
Array Bridge provides products and services that and documentation. Further, we can help you with ELISA
address two important areas in the development of method qualification or validation. The company also
biologics: biosimilar drug comparability analysis and provides consultation for the development of an effective
impurity analysis. impurity analysis strategy, enabling your program(s) to
meet requirements from regulatory agencies such as FDA
During biosimilar development, biologics comparability and EMA.
is critical to the successful development of the process
and product. From cell line selection to process develop- Array Bridge provides value to our customers through
ment, from formulation development to change control, high quality products and services, and we help you
comparability is closely related to the molecule’s safety develop biologics including biosimilars successfully.
and efficacy. Array Bridge has developed ‘antibody arrays’
to measure biosimilar drug comparability at the molecular
level, providing a sensitive, systematic and robust mea-
surement of biosimilar conformational comparability.
This antibody array-based technology can be used at all
stages of biosimilar development, from cell line selection and
process development to clinical testing and product release.
For impurity analysis, Array Bridge provides ELISA kits and
reagents for Host Cell Protein quantitation and Western
Blot analysis. All the products are manufactured under
cGMP to ensure quality and consistency. In the near future,
Array Bridge will also provide Q-PCR-based residual DNA
quantitation kits for CHO and E. coli-derived biologics and
an ELISA kit for residual Protein A quantitation.
In addition to these products, Array Bridge also provides
services to the biotech industry. If you need to analyze your
samples for impurities (Host Cell Proteins, residual DNA or
Protein A) or for biosimilar conformational comparability,
Array Bridge has scientists with experience working under
cGMP and ICH guidelines to deliver regulatory-ready results

7. Services
Array Bridge provides services in several areas
1. Biosimilar conformational comparability analysis.
2. HO and E. coli Host Cell Protein quantitation, method development, qualification
C
or validation.
3.Western Blot analysis of HCPs in CHO or E. coli-derived biologics using 1-D and 2-D
gel electrophoresis and 1-D and 2-D Western Blot.
4. evelopment of customer-based biosimilar conformational comparability analysis
D
ELISA and HCP ELISA.
5. roviding consultation on the Host Cell Protein strategy for a specific project
P
or platform.
Contact Information
www.arraybridge.com
Phone: 636-284-4212.
Email: support@arraybridge.com
4320 Forest Park Avenue. Ste. 303
St. Louis, MO 63108
ARB-1125