4. Table of contents
1 Introduction ....................................................................................................................................................4
2 Comparability exercise .......................................................................................................................5
3 Quality .....................................................................................................................................................5
4 Stability ..................................................................................................................................................9
5 Manufacturing Process...............................................................................................................................9
6 Similarity Determination .....................................................................................................................10
7 Data Organization...............................................................................................................................10
8 References ..................................................................................................................................................11
Guide for conduction of comparability exercise for biological product registration 3
5. 1
Introduction
This Guide is for the conduction of comparability exercise for biological product registration by comparability development,
according to the specific legislation (Resolution RDC No. 55/10 and its updates). The aim of this Guide is to clarify the regulatory
requirements for the comparability exercise with regard to the product quality criteria, required for registration of a biological product
by comparability development in Anvisa. This Guide addresses only the requirements for comparability study in relation to the quality
attributes, being that all other items of specific standards must be complied with for the product’s health registration.
If the applicant is able to evidence the comparability of the products by other scientifically and technically more viable studies, the
data presented will be considered and evaluated by ANVISA.
The decisions made with regard to the licensing of biological products must be scientifically evidenced. Thus the company that wishes
to register a biological product by comparability development must present the evidences required to prove all the necessary aspects in
relation to quality, safety and efficacy of the product, during application of a registration.
Likewise any drug development program, development of a biological product by comparability development includes a gradual
focus, starting with characterization and evaluation of the product quality attributes, followed by nonclinical and clinical studies. Full
characterization and comparison in the level of quality are the foundations for a possible reduction of data in the nonclinical and
clinical development. If differences between the biological product (BP) and the comparer biological product (CBP) are found, in any stage,
the fundamental reasons for the differences must be investigated. These differences must always be explained and justified, being that
additional data, such as safety data, may be required.
In addition to the quality data, the BP registration requires nonclinical and clinical data generated with the product per se. The
requirements for presentation of nonclinical and clinical data will be addressed in this guide and must follow the standard in effect and
other specific guides. The quantity of nonclinical and clinical data deemed necessary will depend on the product or class of products;
level of possible characterization used, with modern analytical methods; differences observed or potential differences of the BP and
CBP and the clinical experience with the product class. A case-by-case analysis is clearly required for each product class.
A BP must be similar to the licensed CBP, for which safety and efficacy are substantially evidenced through presentation of a
complete dossier. The possibility of a BP being authorized, based on reduced nonclinical and clinical data, depends on
evidence of its similarity with an appropriate BP through the comparability exercise. The manufacturers must show a
full understanding of the manufacturing of their product, of its uniform and robust manufacture, and present a complete
quality dossier that includes a full characterization of the product.
The comparability exercise between the BP and CBP in the aspect of quality is an additional element in the traditional complete
quality dossier. The pharmaceutical form and route of administration of the BP must be the same as for the CBP.
The studies must be comparative, using analytical methods sensitive to the detection of differences in potential between the BP and
CBP. The main clinical studies must use the final formula derived from the final material of the BP manufacturing process. Otherwise,
additional evidence of comparability may be required to demonstrate that the BP to be sold is comparable to that used in the main
clinical studies.
The comparability exercise must always use the same CBP, being that this must be the molecule registered in Brazil based on a
complete dossier.
4 Guide for conduction of comparability exercise for biological product registration
6. 2 Comparability exercise
The comparability exercise for a BP is structured to indicate that the BP has highly similar quality attributes when compared to the
CBP. However, it also includes the nonclinical and clinical studies that provide an integrated collection of comparative data. The
comparability data, in the quality level, may function as a set of data in addition to that usually required for an originator product
developed as a new and independent product. This is the basis to enable reduction of nonclinical and clinical data requirements.
For the comparability exercise to be consistent there is the need to ideally evaluate the product during the stages of the most
appropriate manufacturing process to detect a change in the quality attributes. In most cases, this can be limited to the active
ingredient and pharmaceutical product and can lead to evaluation of these latter ones. The number of studies required to demonstrate
comparability will depend on:
• nature of the product;
• availability of suitable analysis techniques that allow detection of possible divergences;
• relation between the quality attributes and the efficacy and safety profile of the product;
With the aim of demonstrating the comparability of two products, the manufacturer must evaluate, fro example:
• the physical-chemical and biological characterization data pertinent and related to the quality attributes;
• the results of analyses on pertinent samples collected in appropriate stages of the manufacturing process (of the active
ingredient as well as finished product)
• the data on stability, including data obtained after accelerated stability studies or under conditions of stress, to better
understand the potential differences of the product breakdown routes and potential differences related to the substances and
impurities associated with the product;
• the data obtained from countless batches of the biological product and comparer product to aid in the characterization of
possible differences. This does not suppose that there is need to conduct all the tests for all the batches; a matrix method can be
used if rationalized.
One must also determine fi the results provide indications on:
• the critical control points of the manufacturing process that have influence on the product characteristics;
• accuracy of the controls during the manufacturing, including critical control points and analyses during the
manufacturing;
• type and scope of the data that must be obtained after the clinical and nonclinical studies on the biological product.
If during the comparability exercise significant differences are detected that cannot be justified between the BP and CBP, there
will be an indication that the products are not similar. In such cases, the product must follow the individual development route for
registration and more extensive nonclinical and clinical data will be required.
3 Quality
Comparison of quality, showing molecular similarity between the BP and CBP is essential to justify that the clinical safety and
efficacy profile of the B would be potentially similar to the CBP so as to be able to reduce the level of nonclinical and clinical data
required for the BP. In ideal conditions, the development of a BP involves full characterization
7. Guide for conduction of comparability exercise for biological product registration 5
8. of various batches representing the CBP and, later, the design of a manufacturing process that will reproduce a product highly similar
to the CBP in all clinically relevant quality attributes; that is, those attributes that would have repercussion on the clinical
performance. A BP is, in general, derived from another master cell bank that uses independent manufacturing processes and control.
These must be selected and outlined to meet the necessary comparability requirements. A full technical report from the active
ingredient to the finished biological product will always be required.
A greater knowledge of the relation between the biochemical, physical-chemical and biological properties of the product and clinical
results will facilitate the development of a BP. Due to the heterogeneous nature of proteins (especially those with extensive post-
translational modifications, such as glycoproteins), the limitations of some analytical techniques and the usually unpredictable nature
of the clinical consequences of small differences in the structural/physical-chemical properties of protein, the comparability evaluation
will have to be conducted independently for each product. Thus, all differences detected between the BP and the CBP will have to be
evaluated and discussed, as well as their clinical relevance.
In addition to the complete set of data on the chemistry and manufacturing required, the set of data presented in relation to a biological
product to be registered by comparability development must support a great number of data, aiming at demonstrating the similarity
with the CBP, including a detailed characterization of the BP and CBP. In order for a biological product to be registered by
comparability development, the similarity must be essentially determined through strict and extensive studies. To evaluate the
comparability, the manufacturer must make a full physical-chemical and biological characterization in direct comparisons with the
CBP. All quality aspects and product heterogeneity must be evaluated.
Due to the non-availability of the active ingredient isolated for the CBP, the BP manufacturer will normally be using a finished CBP
for the comparability exercise. The finished biological product, by definition, will be in the final dosage form containing the active
ingredient(s) formulated with the excipients. In cases where the excipients do not limit the sensitivity of the tests used for the
characterization, the study can be conducted through the finished CBP.
However, conducting the studies by comparing the active ingredients can have some advantages or in some cases by the only scientific
option. If the comparer active ingredient used for the characterization is isolated from a CBP, one must demonstrate through
additional studies that the active ingredient was not altered by occasion of the isolation process. One of the ways of qualifying the
isolation process consists of subjecting the BP formulated to the same extraction process as the CBP and comparing the active
ingredient of the CBP thus extracted (without formula) to the active ingredient of the BP obtained before the formulation. All the
methods used must be justified.
The high level of similarity between a BP and CBP is based on the reduction of licensing nonclinical and clinical requirements.
However, some differences may likely be found, for example, due to differences in impurities or excipients. Such differences must be
evaluated with regard to their potential impacts on the clinical safety and efficacy of a BP and a justification, such as, for example, the
study results themselves or bibliographical data that allows such differences, must be provided. The unknown differences of clinical
relevance, particularly those related to safety, may have to be addressed in other studies before or after the sale. Differences in the
quality attributes that have a potential impact on the clinical activity will influence in the determination to consider such product for
registration by comparability development.
3.1 Considerations Related to Quality:
3.1.1 Analysis techniques:
Although the power of the analytical methods for characterization of the proteins has increased drastically in recent years, there are
sill obstacles in the complete characterization of complex biological products. A series of modern analyses are required to determine
the structure, function, purity and heterogeneity of the products. The methods used must separate and analyze different variants of the
product based on different subjacent chemical, physical and biological properties of the protein molecules. For example, PAGE, ion
exchange chromatograph, isoelectric focusing and capillary electrophoresis, all these separate proteins based on the load, but do so
under different conditions, taking into account different physical-chemical properties. As a result, one method can detect variants that
another method does not detect. The aim of the comparability investigation is to be as complete as possible, in order to minimize the
possibility of undetected differences between the CBP and BP that can have repercussion in the clinical activity. The analytical
limitations of each technique (e.g. sensitivity limits, power of resolution) must be considered on determining the similarity between
the BP and CBP.
The series of tests to be conducted in the scope of the comparability exercise must be chosen carefully and optimized so as to
maximize detection of differences in the quality attributes between BP and CBP. It may be opportune to modify the tests used in the
BP elaboration process or to add new tests. With the aim of examining the full range of physical-chemical properties and biological
activities, more than one analysis technique may be required to evaluate the same quality attribute.
6 Guide for conduction of comparability exercise for biological product registration
9. In such cases, techniques based on different physical-chemical or biological principles will have to be used to collect the data
associated with a single parameter so as to maximize the detection of potential differences between the BP and CBP.
The methods used to measure the quality attributes by release of batches as well as the methods used in the
comparability exercise must be validated according to the standards in effect. In the registration application, a full
description of the analytical techniques used to release and characterize the product must be provided.
3.1.2
Characterization
Full characterization of both the BP and CBP must be done with biochemical, biophysical techniques and modern and suitable
biological analytical techniques. For the active ingredient(s), details must be provided on the structure of primary and greater order,
the post-translational changes (including but not limited to the glycoforms), the biological activity, purity, impurities, substances
(variants) related to the product (active ingredient) and the immunochemical properties, when pertinent.
During a comparability exercise, direct characterization studies are required that compare the BP and CBP. The primary structure of
the BP and CBP must be identical.
If differences between the BP and CBP are found, their potential impacts on the safety and efficacy of the BP must be evaluated. The
predefined limits must be considered in advance. Evaluation of the results must include investigation of the differences found between
the BP and CBP. This determination will be based on knowledge of the relation between the quality attributes of the product and
clinical activity of the CBP and related products, on the clinical history of the CBP and differences of each batch of the BP from the
commercial batches of the CBP. For example, the quality attributes must be justified, as well as composition and profile of the
glycosylation, biological activity known to be related to the clinical activity and binding activity of the receptor. However, an
additional characterization may be required in certain cases. Therefore, when the characterization profiles are different, one must
evaluate the importance of these differences.
Knowledge of the analytical limitations of each technique used to characterize the product (e.g. sensitivity limits, power of resolution)
must be applied in determining the similarity. Raw data must be provided for all the complex analytical methods (e.g. high quality
reproductions of the gels, chromatographs, etc.) in addition to tabular data summarizing the complete set of data and showing the
results of all release and characterization analyses conducted with the BP and CBP.
Characterization of a biological/biotechnological product through appropriate techniques involves determination of the physical-
chemical properties, biological activity, immunochemical properties (if applicable), purity, impurities, contaminants and quantity.
Each one of the following criteria must be viewed as essential to conduction of the comparability exercise:
3.1.3 Physical-chemical properties
The manufacturer, when it elaborates and performs a comparability exercise, must consider the concept of the desired product (and its
variations). It must also consider the complexity of the molecular entity, namely the level of molecular heterogeneity. The
manufacturer must try to demonstrate that the structures of higher order (secondary, tertiary and quaternary, if applicable) are
compatible through the use of suitable analytical methods (e.g. mass spectrometry, nuclear magnetic resonance). If it is not possible to
obtain the data required in relation to the structures of higher order, a pertinent biological activity test can enable verification of a
correct conformation.
An inherent level of structural heterogeneity can occur in proteins, due to the process of biosynthesis, being that the BP and CBP will
probably contain a mixture of the post-translationally modified forms. These forms and their potential differences must be duly
investigated, identified, characterized and quantified and their impact analyzed.
3.1.4 Biological activity
The biological activity is the ability or specific capacity of the product to obtain a defined biological effect. It is used for several
purposes in the evaluation of product quality and is required to characterize and analyze batches. In ideal conditions, the biological
evaluation will reflect the mechanism included in the protein action and, therefore, will serve as a link to the clinical activity.
Biological evaluation is a measure of quality of the “function” of the protein product and can be used to determine if a variant of a
product has the suitable level of the activity (that is, a substance related to the product), or if it is inactive (which is therefore
defined as an impurity). Biological evaluation also complements the physical-chemical analyses on confirming the
correct structure of higher order of the molecule. Thus, the use of a relevant biological assay, of suitable accuracy,
is an important way of confirming that there is no significant functional difference between the BP and CBP.
Guide for conduction of comparability exercise for biological product registration 7
10. The manufacturer must take into account the limits of the biological tests, like the strong level of variability, which can hinder
detection of differences between two very similar products.
In cases in which the biological tests are sued as complement to the physical-chemical analyses, for example, while a surrogate test for
analysis of the structures of higher order, a pertinent, sufficiently precise and accurate biological test can be an acceptable means of
confirming the absence of alteration in the structures of higher order. In cases in which the physical-chemical and biological tests are
not regarded as acceptable means of confirming the preservation of the structure of higher order, it is possible to use data from clinical
and nonclinical studies. However, if the use of such studies is required, one must consider if it is really viable to register the product
by comparability development.
When the products compared have multiple biological activities, the manufacturers must perform a series of pertinent functional tests
conceived to evaluate the range of the activities. These activities can result in countless functional fields. In such situations, all
functional activities must be evaluated in the scope of the comparability study.
Potency is the quantitative measure of the biological activity. A relevant and validated potency test must be part of the active
ingredient and/or finished product specification, as well as of the comparability exercise.
The results of the potency test must be provided and expressed in the units of the activity. When possible (for example, for in vitro
biochemical analyses, like enzyme tests or binding tests), the results may be expressed in specific activities (e.g. unit/mg of protein).
The tests must be calibrated by a national or international standard or reference standard, when available and appropriate. Therefore,
international or national and reactive reference standards must be used to determine the potency and to express results in IU or U.
These standards are not conceived for use as a CBP during the comparability exercise.
The biological analyses may be used for purposes other than potency determination. For example, a relevant biological test is essential
to determine if the antibodies developed in response to the product have neutralizing activity that has repercussion on the biological
activity of the product and/or endogenous counterparts, if present.
When the compared products have multiple biological activities, the manufacturers must conduct a series of pertinent functional tests
conceived to evaluate the range of activities. These activities can result in countless functional fields. In such situations, all functional
activities must be evaluated in the scope of the comparability study.
3.1.5- Immunochemical properties
When the characterization also includes the immunochemical properties (e.g. in the cases of antibodies or antibody-based products),
the manufacturer must confirm that the BP is equivalent to the CBP, in terms of specificity, affinity, bond kinetics, Fc functional
activity, when pertinent.
3.1.6-Purity and impurities
The impurities related to the process and product must be identified, quantified with state-of-the-art technology and compared
between the BP and CBP. Some differences will be expected because the proteins are produced by different manufacturing processes.
If significant differences are observed in the impurity profile between the BP and CBP, their potential impact on the efficacy and
safety, including immunogenicity, must be evaluated and discussed. It is essential to conduct appropriate tests to verify the impurities
related to the process, specific for the cell line used for the production.
The combination of analysis techniques chosen must generate data that allows evaluation of the pertinent differences with regard to
the purity profiles.
If differences are observed in the level of purity profile and impurity profile of the BP in relation to the CBP, these differences must
be evaluated and justified so that people can determine the potential incidence on the safety and efficacy. When the BP has a different
impurity profile, these impurities must be identified and characterized. According to the type and amount of impurities, the conduction
of clinical and nonclinical studies will enable confirmation that there is no negative effect with regard to the safety and efficacy of the
biological product to be registered.
3.1.7- Specifications
The tests and analyses chosen to define the specifications of the drug substance or of the finished product are not regarded, separately,
as suitable to evaluate the differences, since they are chosen to serve as routine quality control and not to make a complete
characterization. The manufacturer must confirm that the specifications chosen for the BP can assure the product quality more
adequately.
8 Guide for conduction of comparability exercise for biological product registration
11. Specifications are used to evidence the current quality of the active ingredient and of the finished biological product, instead of fully
characterizing them. The specifications for the BP must be established as described in the guidelines and monographs established,
when these exist. Note that the pharmacopoeial monographs may contain only a minimum set of requirements of a particular product
and additional test parameters may be required. Reference to the analytical methods used and the acceptance limits for each BP test
parameter must be provided and justified. All analytical methods referred to in the specification must be validated; the corresponding
validation must be documented.
The specifications for a BP may not be the same for the CBP, since the manufacturing processes will be different and different
analytical and lab procedures for the tests will be used. However, the specifications must capture and control the known important
quality attributes of the product for the CBP (e.g. correct identity, purity, potency, molecular heterogeneity, in terms of size, load and
hydrophobicity, if relevant, level of sialylation, number of individual polypeptide chains, glycosylation of a functional domain, levels
of aggregation, impurities, such as proteins and DNA of the host cell); the specifications must be based on the
manufacturer’s experience with the BP (e.g. manufacturing history, test capacity, safety and efficacy profile of the
product), and the experimental results obtained, through the test, and comparing the BP with the CBP. Sufficient batches
of the BP must be used in the specifications established. The manufacturer must demonstrate, whenever possible, that the
limits established for a given specification are not significantly greater than the range of variability off the CBP during the
maximum storage period of the product, unless justified.
4 Stability
In the case of certain manufacturing processes, even minimal variations between the BP and CBP manufacturing stages can cause
differences in the stability of the products.
In exceptional cases, it may be useful or necessary to conduct comparative stability tests in real time/real conditions of preservation
with BP and CBP to compare the stability of both products in the same storage conditions. In certain cases, it may be possible and
even advantageous to conduct stability studies side by side on samples that were combined, as far as possible, in function of
the manufacturing date. However, these situations are rarely presented and are not mandatory. The comparative stability tests in real
time will only be required in exceptional and specific cases, such as when there is need to use the stability study as a tool to detect
subtle differences between the BP and CBP where the characterization studies do not allow this evaluation. For example, the presence
of vestiges of a protease can only be detected by a breakdown of the product that occurs for a long period. In certain cases, the
stability profile must be altered if divalent ions pass through the container closing system, since there will be activation of vestiges of
the proteases. The studies conducted in real time only with the biological product to be registered will always be required.
In turn, the accelerated breakdown studies and studies in conditions of stress are recommended and often prove to be useful tools to
establish breakdown profiles and can thus contribute toward direct comparison between the BP and CBP. The results thus obtained
can reveal differences between the products that would justify additional evaluations. One must consider conducting suitable tests to
ensure that the samples and storage conditions are adequate.
The stability studies conducted during the comparability exercise must be conducted according to Resolution RDC No. 50/11 and its
updates.
5 Manufacturing Process
The elaboration of a BP must be based on a fully designed production process that considers all relevant guidelines. The manufacturer
must demonstrate the uniformity and robustness of the manufacturing process, executing Good Manufacturing Practices, modern
quality control and assurance procedures, internal process controls and process validation. The manufacturing process must meet the
standards in effect for Good Manufacturing Practices and must be optimized to minimize the differences between the BP and CBP and
any predictable impact on the clinical safety and efficacy of the product. Some differences between the BP and CBP are expected and
will be acceptable, provided suitable justification is provided with regard to the negative impact on clinical performance.
Guide for conduction of comparability exercise for biological product registration 9
12. It is understood that a manufacturer developing a BP does not have access to the confidential details of the CBP’s manufacturing
process, such that the process will differ from the process licensed for the CBP (unless there is a contractual provision with the
manufacturer of the CBP). The manufacturing process of a BP must use state-of-the-art science and technology to obtain a high-
quality BP that is as similar as possible to the CBP. This will involve a broad evaluation of the CBP before developing the BP
manufacturing process. The BP manufacturer must unite all available knowledge on the CBP with regard to the type of host cell,
formula and container closing system used to sell the CBP. Where applicable, the BP manufacturer must determine the potential
impact on alteration of any of these elements, on quality, safety and efficacy of the product, based on evidences available from public
information and experience with previous use of the CBP. The BP manufacturer must apply this knowledge on designing the
manufacturing process. The justification for accepting these differences must be demonstrated based on concrete scientific and clinical
experiences, with the BP as well as the CBP.
As a general rule, the product must be expressed and produced in the same type of host cell as the CBP to minimize the potential of
important changes in the critical attributes of quality of the protein, and to prevent introduction of certain types of impurities related to
the process that may have repercussion on the clinical results and immunogenicity. If the type of host cell for manufacture of the BP
only is changed, the product must be registered by individual development and one must convincingly demonstrate that the product’s
clinical profile will not be altered.
A complete package must be presented with description and data outlining the manufacturing process, starting with the development
of expression vectors and cell banks, cell culture/fermentation, collection, purification reactions and modification, insertion in bulk or
final containers, and storage. The development studies conducted to establish and validate the form and formula of the dosage, and the
container closing system (including integrity to prevent microbial contamination), and the use directions, must also be documented.
6 Similarity Determination
Final determination of the similarity must be based on the following elements: analyses, biological assays and data obtained from
clinical and nonclinical studies. However, for a certain product to be regarded as a biological product liable to registration by
comparability, majority of the data must result from an analytical and biological characterization similar to that of the CBP.
It may not be adequate to consider a product as viable for registration by comparability development in the following cases:
i) the analysis techniques used do not allow one to distinguish the pertinent differences that may have impact on the safety and
efficacy of the product;
ii) the link between certain quality attributes, like safety and efficacy, was not established and it is likely that there are differences
between the quality attributes of the BP and CBP.
In such cases, one must use individual development to register the product, performing all the necessary stages to evidence its quality,
efficacy and safety according to the standard in effect.
7 Data Organization
Although the quality comparisons are used in several points in the entire application/quality dossier, a distinction must be made
between usual quality data requirements and those presented as part of the comparability exercises. The ideal is for all comparability
data to be presented in a separate and duly identified section in the quality module.
10 Guide for conduction of comparability exercise for biological product registration
13. 8 References
- Guidelines on evaluation of similar biotherapeutic products (SEBs). WHO, http://www.biosimilars.ca/docs/BIOTHERAPEUTICS_
FOR_WEB_22APRIL2010.pdf ; 2009 Oct..
- Guidance for Sponsors: Information and Submission Requirements for Subsequent Entry Biologics (SEBs). Health Canada;
2010 Mar.
Guide for conduction of comparability exercise for biological product registration 11
