Guideline for Industry
Quality of Biotechnological
Products: Stability Testing of
Biotechnological/Biological
Products
July 1996
ICH Q5C Table of Contents
I. INTRODUCTION (1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
II. SCOPE OF THE ANNEX (2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
III. TERMINOLOGY (3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
IV. SELECTION OF BATCHES (4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
A. Drug Substance (Bulk Material) (4.1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
B. Intermediates (4.2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
C. Drug Product (Final Container Product) (4.3) . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
D. Sample Selection (4.4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
V. STABILITY-INDICATING PROFILE (5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
A. Protocol (5.1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
B. Potency (5.2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
C. Purity and Molecular Characterization (5.3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
D. Other Product Characteristics (5.4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
VI. STORAGE CONDITIONS (6) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
A. Temperature (6.1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
B. Humidity (6.2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
C. Accelerated and Stress Conditions (6.3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
D. Light (6.4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
E. Container/Closure (6.5) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
F. Stability after Reconstitution of Freeze-Dried Product (6.6) . . . . . . . . . . . . . . . . 8
VII. TESTING FREQUENCY (7) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
VIII. SPECIFICATIONS (8) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
IX. LABELING (9) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
X. GLOSSARY (10) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
i GUIDELINE FOR INDUSTRY 1
QUALITY OF BIOTECHNOLOGICAL PRODUCTS: STABILITY
TESTING OF BIOTECHNOLOGICAL/BIOLOGICAL
PRODUCTS
I. INTRODUCTION (1)
The guidance stated in the ICH harmonized tripartite guideline entitled Stability Testing of New
Drug Substances and Products (issued by ICH on October 27, 1993) applies in general to
biotechnological/biological products.  However, biotechnological/biological products have
distinguishing characteristics to which consideration should be given in any well-defined testing
program designed to confirm their stability during the intended storage period.  For such products
in which the active components are typically proteins and/or polypeptides, maintenance of
molecular conformation and, hence, of biological activity, is dependent on noncovalent as well as
covalent forces.  The products are particularly sensitive to environmental factors such as
temperature changes, oxidation, light, ionic content, and shear.  To ensure maintenance of
biological activity and to avoid degradation, stringent conditions for their storage are usually
necessary.
The evaluation of stability may necessitate complex analytical methodologies.  Assays for
biological activity, where applicable, should be part of the pivotal stability studies.  Appropriate
physicochemical, biochemical, and immunochemical methods for the analysis of the molecular
entity and the quantitative detection of degradation products should also be part of the stability
program whenever purity and molecular characteristics of the product permit use of these
methodologies.
With these concerns in mind, the applicant should develop the proper supporting stability data for
a biotechnological/biological product and consider many external conditions that can affect the
1 This guideline was developed within the Expert Working Group (Quality) of the International Conference on
Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) and has been
subject to consultation by the regulatory parties, in accordance with the ICH process.  This document has been endorsed
by the ICH Steering Committee at  Step 4 of the ICH process, November 20, 1995.  At  Step 4 of the process, the final
draft is recommended for adoption to the regulatory bodies of the European Union, Japan and the USA.  This guideline
was published in the Federal Register  on July 10, 1996 (61 FR 36466) and is applicable to drug and biological
products.  Although this guideline does not create or confer any rights for or on any person and does not operate to bind
FDA or the industry, it does represent the agencys current thinking on stability testing of biotechnological/biological
products.  For additional copies of this guideline, contact the Drug Information Branch, HFD-210, CDER, FDA, 5600
Fishers Lane, Rockville, MD 20857 (Phone: 301-827-4573) or the Manufacturers Assistance and Communication Staff
(HFM-42), CBER, FDA, 1401 Rockville Pike, Rockville, MD 20852-1448.  Send one self-addressed adhesive label to
assist the offices in processing your request.  An electronic version of this guidance is also available via Internet using
the World Wide Web (WWW) (connect to the CDER Home Page at http://www.fda.gov/cder and go to the Regulatory
Guidance section). product's potency, purity, and quality.  Primary data to support a requested storage period for
either drug substance or drug product should be based on long-term, real-time, real-condition
stability studies.  Thus, the development of a proper long-term stability program becomes critical
to the successful development of a commercial product.  The purpose of this document is to give
guidance to applicants regarding the type of stability studies that should be provided in support of
marketing applications.  It is understood that during the review and evaluation process, continuing
updates of initial stability data may occur.
II. SCOPE OF THE ANNEX (2)
The guidance stated in this annex to Stability Testing of New Drug Substances and Products
applies to well-characterized proteins and polypeptides, their derivatives and products of which
they are components, and which are isolated from tissues, body fluids, cell cultures, or produced
using recombinant deoxyribonucleic acid (r-DNA) technology.  Thus, the document covers the
generation and submission of stability data for products such as cytokines (interferons,
interleukins, colony-stimulating factors, tumor necrosis factors), erythropoietins, plasminogen
activators, blood plasma factors, growth hormones and growth factors, insulins, monoclonal
antibodies, and vaccines consisting of well-characterized proteins or polypeptides.  In addition,
the guidance outlined in the following sections may apply to other types of products, such as
conventional vaccines, after consultation with the appropriate regulatory authorities.  The
document does not cover antibiotics, allergenic extracts, heparins, vitamins, whole blood, or
cellular blood components.
III. TERMINOLOGY (3)
For the basic terms used in this annex, the reader is referred to the Glossary in Stability Testing
of New Drug Substances and Products.  However, because manufacturers of
biotechnological/biological products sometimes use traditional terminology, traditional terms are
specified in parentheses to assist the reader.  A supplemental glossary is also included that
explains certain terms used in the production of biotechnological/biological products.
IV. SELECTION OF BATCHES (4)
A. Drug Substance (Bulk Material) (4.1)
Where bulk material is to be stored after manufacture, but before formulation and final
manufacturing, stability data should be provided on at least three batches for which
manufacture and storage are representative of the manufacturing scale of production.  A
minimum of 6 months stability data at the time of submission should be submitted in cases
where storage periods greater than 6 months are requested.  For drug substances with
storage periods of less than 6 months, the minimum amount of stability data in the initial
submission should be determined on a case-by-case basis.  Data from pilot-plant scale
batches of drug substance produced at a reduced scale of fermentation and purification
2 may be provided at the time the dossier is submitted to the regulatory agencies with a
commitment to place the first three manufacturing scale batches into the long-term
stability program after approval.
The quality of the batches of drug substance placed into the stability program should be
representative of the quality of the material used in preclinical and clinical studies and of
the quality of the material to be made at manufacturing scale.  In addition, the drug
substance (bulk material) made at pilot-plant scale should be produced by a process and
stored under conditions representative of that used for the manufacturing scale.  The drug
substance entered into the stability program should be stored in containers that properly
represent the actual holding containers used during manufacture.  Containers of reduced
size may be acceptable for drug substance stability testing provided that they are
constructed of the same material and use the same type of container/closure system that is
intended to be used during manufacture.
B. Intermediates (4.2)
During manufacture of biotechnological/biological products, the quality and control of
certain intermediates may be critical to the production of the final product.  In general, the
manufacturer should identify intermediates and generate in-house data and process limits
that assure their stability within the bounds of the developed process.  Although the use of
pilot-plant scale data is permissible, the manufacturer should establish the suitability of
such data using the manufacturing scale process.
C. Drug Product (Final Container Product) (4.3)
Stability information should be provided on at least three batches of final container
product representative of that which will be used at manufacturing scale.  Where possible,
batches of final container product included in stability testing should be derived from
different batches of bulk material.  A minimum of 6 months data at the time of submission
should be submitted in cases where storage periods greater than 6 months are requested. 
For drug products with storage periods of less than 6 months, the minimum amount of
stability data in the initial submission should be determined on a case-by-case basis. 
Product expiration dating should be based upon the actual data submitted in support of the
application.  Because dating is based upon the real-time/real-temperature data submitted
for review, continuing updates of initial stability data should occur during the review and
evaluation process.  The quality of the final container product placed on stability studies
should be representative of the quality of the material used in the preclinical and clinical
studies.  Data from pilot-plant scale batches of drug product may be provided at the time
the dossier is submitted to the regulatory agencies with a commitment to place the first
three manufacturing scale batches into the long-term stability program after approval. 
Where pilot-plant scale batches were submitted to establish the dating for a product and,
in the event that the product produced at manufacturing scale does not meet those
3 long-term stability specifications throughout the dating period or is not representative of
the material used in preclinical and clinical studies, the applicant should notify the
appropriate regulatory authorities to determine a suitable course of action.
D. Sample Selection (4.4)
Where one product is distributed in batches differing in fill volume (e.g., 1 milliliter (mL),
2 mL, or 10 mL), unitage (e.g., 10 units, 20 units, or 50 units), or mass (e.g., 1 milligram
(mg), 2 mg, or 5 mg), samples to be entered into the stability program may be selected on
the basis of a matrix system and/or by bracketing.
Matrixing, i.e., the statistical design of a stability study in which different fractions of
samples are tested at different sampling points, should only be applied when appropriate
documentation is provided that confirms that the stability of the samples tested represents
the stability of all samples.  The differences in the samples for the same drug product
should be identified as, for example, covering different batches, different strengths,
different sizes of the same closure, and, possibly, in some cases, different container/closure
systems.  Matrixing should not be applied to samples with differences that may affect
stability, such as different strengths and different containers/closures, where it cannot be
confirmed that the products respond similarly under storage conditions.
Where the same strength and exact container/closure system is used for three or more fill
contents, the manufacturer may elect to place only the smallest and largest container size
into the stability program, i.e., bracketing.  The design of a protocol that incorporates
bracketing assumes that the stability of the intermediate condition samples are represented
by those at the extremes.  In certain cases, data may be needed to demonstrate that all
samples are properly represented by data collected for the extremes.
V. STABILITY-INDICATING PROFILE (5)
On the whole, there is no single stability-indicating assay or parameter that profiles the stability
characteristics of a biotechnological/biological product.  Consequently, the manufacturer should
propose a stability-indicating profile that provides assurance that changes in the identity, purity,
and potency of the product will be detected.
At the time of submission, applicants should have validated the methods that comprise the
stability-indicating profile, and the data should be available for review.  The determination of
which tests should be included will be product-specific.  The items emphasized in the following
subsections are not intended to be all-inclusive, but represent product characteristics that should
typically be documented to demonstrate product stability adequately.
A. Protocol (5.1)
4 The dossier accompanying the application for marketing authorization should include a
detailed protocol for the assessment of the stability of both drug substance and drug
product in support of the proposed storage conditions and expiration dating periods.  The
protocol should include all necessary information that demonstrates the stability of the
biotechnological/biological product throughout the proposed expiration dating period
including, for example, well-defined specifications and test intervals.  The statistical
methods that should be used are described in the tripartite guideline on stability.
B. Potency (5.2)
When the intended use of a product is linked to a definable and measurable biological
activity, testing for potency should be part of the stability studies.  For the purpose of
stability testing of the products described in this guideline, potency is the specific ability or
capacity of a product to achieve its intended effect.  It is based on the measurement of
some attribute of the product and is determined by a suitable in vivo or in vitro
quantitative method.  In general, potencies of biotechnological/biological products tested
by different laboratories can be compared in a meaningful way only if expressed in relation
to that of an appropriate reference material.  For that purpose, a reference material
calibrated directly or indirectly against the corresponding national or international
reference material should be included in the assay.
Potency studies should be performed at appropriate intervals as defined in the stability
protocol and the results should be reported in units of biological activity calibrated,
whenever possible, against nationally or internationally recognized standards.  Where no
national or international reference standards exist, the assay results may be reported in
in-house derived units using a characterized reference material.
In some biotechnological/biological products, potency is dependent upon the conjugation
of the active ingredient(s) to a second moiety or binding to an adjuvant.  Dissociation of
the active ingredient(s) from the carrier used in conjugates or adjuvants should be
examined in real-time/real-temperature studies (including conditions encountered during
shipment).  The assessment of the stability of such products may be difficult because, in
some cases, in vitro tests for biological activity and physicochemical characterization are
impractical or provide inaccurate results.  Appropriate strategies (e.g., testing the product
before conjugation/binding, assessing the release of the active compound from the second
moiety, in vivo assays) or the use of an appropriate surrogate test should be considered to
overcome the inadequacies of in vitro testing.
C. Purity and Molecular Characterization (5.3)
For the purpose of stability testing of the products described in this guideline, purity is a
relative term.  Because of the effect of glycosylation, deamidation, or other
heterogeneities, the absolute purity of a biotechnological/biological product is extremely
5 difficult to determine.  Thus, the purity of a biotechnological/biological product should be
typically assessed by more than one method and the purity value derived is
method-dependent.  For the purpose of stability testing, tests for purity should focus on
methods for determination of degradation products.
The degree of purity, as well as the individual and total amounts of degradation products
of the biotechnological/biological product entered into the stability studies, should be
reported and documented whenever possible.  Limits of acceptable degradation should be
derived from the analytical profiles of batches of the drug substance and drug product
used in the preclinical and clinical studies.
The use of relevant physicochemical, biochemical, and immunochemical analytical
methodologies should permit a comprehensive characterization of the drug substance
and/or drug product (e.g., molecular size, charge, hydrophobicity) and the accurate
detection of degradation changes that may result from deamidation, oxidation,
sulfoxidation, aggregation, or fragmentation during storage.  As examples, methods that
may contribute to this include electrophoresis (SDS09Page, immunoelectrophoresis,
Western blot, isoelectrofocusing), high-resolution chromatography (e.g., reversed-phase
chromatography, gel filtration, ion exchange, affinity chromatography), and peptide
mapping.
Wherever significant qualitative or quantitative changes indicative of degradation product
formation are detected during long-term, accelerated, and/or stress stability studies,
consideration should be given to potential hazards and to the need for characterization and
quantification of degradation products within the long-term stability program.  Acceptable
limits should be proposed and justified, taking into account the levels observed in material
used in preclinical and clinical studies.
For substances that cannot be properly characterized or products for which an exact
analysis of the purity cannot be determined through routine analytical methods, the
applicant should propose and justify alternative testing procedures.
D. Other Product Characteristics (5.4)
The following product characteristics, though not specifically relating to
biotechnological/biological products, should be monitored and reported for the drug
product in its final container:
Visual appearance of the product (color and opacity for solutions/suspensions; color,
texture, and dissolution time for powders), visible particulates in solutions or after the
reconstitution of powders or lyophilized cakes, pH, and moisture level of powders and
lyophilized products.
6 Sterility testing or alternatives (e.g., container/closure integrity testing) should be
performed at a minimum initially and at the end of the proposed shelf life.
Additives (e.g., stabilizers, preservatives) or excipients may degrade during the dating
period of the drug product.  If there is any indication during preliminary stability studies
that reaction or degradation of such materials adversely affect the quality of the drug
product, these items may need to be monitored during the stability program.
The container/closure has the potential to affect the product adversely and should be
carefully evaluated (see below).
VI. STORAGE CONDITIONS (6)
A. Temperature (6.1)
Because most finished biotechnological/biological products need precisely defined storage
temperatures, the storage conditions for the real-time/real-temperature stability studies
may be confined to the proposed storage temperature.
B. Humidity (6.2)
Biotechnological/biological products are generally distributed in containers protecting
them against humidity.  Therefore, where it can be demonstrated that the proposed
containers (and conditions of storage) afford sufficient protection against high and low
humidity, stability tests at different relative humidities can usually be omitted.  Where
humidity-protecting containers are not used, appropriate stability data should be provided.
  
C. Accelerated and Stress Conditions (6.3)
As previously noted, the expiration dating should be based on real-time/real-temperature
data.  However, it is strongly suggested that studies be conducted on the drug substance
and drug product under accelerated and stress conditions.  Studies under accelerated
conditions may provide useful support data for establishing the expiration date, provide
product stability information or future product development (e.g., preliminary assessment
of proposed manufacturing changes such as change in formulation, scale-up), assist in
validation of analytical methods for the stability program, or generate information that may
help elucidate the degradation profile of the drug substance or drug product.  Studies
under stress conditions may be useful in determining whether accidental exposures to
conditions other than those proposed (e.g., during transportation) are deleterious to the
product and also for evaluating which specific test parameters may be the best indicators
of product stability.  Studies of the exposure of the drug substance or drug product to
extreme conditions may help to reveal patterns of degradation; if so, such changes should
be monitored under proposed storage conditions.  Although the tripartite guideline on
7 stability describes the conditions of the accelerated and stress study, the applicant should
note that those conditions may not be appropriate for biotechnological/biological
products.  Conditions should be carefully selected on a case-by-case basis.
D. Light (6.4)
Applicants should consult the appropriate regulatory authorities on a case-by-case basis to
determine guidance for testing.
E. Container/Closure (6.5)
Changes in the quality of the product may occur due to the interactions between the
formulated biotechnological/biological product and container/closure.  Where the lack of
interactions cannot be excluded in liquid products (other than sealed ampules), stability
studies should include samples maintained in the inverted or horizontal position (i.e., in
contact with the closure), as well as in the upright position, to determine the effects of the
closure on product quality.  Data should be supplied for all different container/closure
combinations that will be marketed.
In addition to the standard data necessary for a conventional single-use vial, the applicant
should demonstrate that the closure used with a multiple-dose vial is capable of
withstanding the conditions of repeated insertions and withdrawals so that the product
retains its full potency, purity, and quality for the maximum period specified in the
instructions-for-use on containers, packages, and/or package inserts.  Such labeling should
be in accordance with relevant national/regional requirements.
F. Stability after Reconstitution of Freeze-Dried Product (6.6)
The stability of freeze-dried products after their reconstitution should be demonstrated for
the conditions and the maximum storage period specified on containers, packages, and/or
package inserts.  Such labeling should be in accordance with relevant national/regional
requirements.
VII. TESTING FREQUENCY (7)
The shelf lives of biotechnological/biological products may vary from days to several years.  Thus,
it is difficult to draft uniform guidelines regarding the stability study duration and testing
frequency that would be applicable to all types of biotechnological/biological products.  With only
a few exceptions, however, the shelf lives for existing products and potential future products will
be within the range of 0.5 to 5 years.  Therefore, the guidance is based upon expected shelf lives
in that range.  This takes into account the fact that degradation of biotechnological/biological
products may not be governed by the same factors during different intervals of a long storage
period.
8 When shelf lives of 1 year or less are proposed, the real-time stability studies should be conducted
monthly for the first 3 months and at 3 month intervals thereafter.  For products with proposed
shelf lives of greater than 1 year, the studies should be conducted every 3 months during the first
year of storage, every 6 months during the second year, and annually thereafter.
While the testing intervals listed above may be appropriate in the preapproval or prelicense stage,
reduced testing may be appropriate after approval or licensure where data are available that
demonstrate adequate stability.  Where data exist that indicate the stability of a product is not
compromised, the applicant is encouraged to submit a protocol that supports elimination of
specific test intervals (e.g., 9-month testing) for postapproval/postlicensure, long-term studies.
VIII. SPECIFICATIONS (8)
Although biotechnological/biological products may be subject to significant losses of activity,
physicochemical changes, or degradation during storage, international and national regulations
have provided little guidance with respect to distinct release and end of shelf life specifications. 
Recommendations for maximum acceptable losses of activity, limits for physicochemical changes,
or degradation during the proposed shelf life have not been developed for individual types or
groups of biotechnological/biological products but are considered on a case-by-case basis.  Each
product should retain its specifications within established limits for safety, purity, and potency
throughout its proposed shelf life.  These specifications and limits should be derived from all
available information using the appropriate statistical methods.  The use of different specifications
for release and expiration should be supported by sufficient data to demonstrate that the clinical
performance is not affected, as discussed in the tripartite guideline on stability.
IX. LABELING (9)
For most biotechnological/biological drug substances and drug products, precisely defined storage
temperatures are recommended.  Specific recommendations should be stated, particularly for drug
substances and drug products that cannot tolerate freezing.  These conditions, and where
appropriate, recommendations for protection against light and/or humidity, should appear on
containers, packages, and/or package inserts.  Such labeling should be in accordance with relevant
national and regional requirements.
X. GLOSSARY (10)
Conjugated Product
A conjugated product is made up of an active ingredient (e.g., peptide, carbohydrate)
bound covalently or noncovalently to a carrier (e.g., protein, peptide, inorganic mineral)
with the objective of improving the efficacy or stability of the product.
Degradation Product
9 A molecule resulting from a change in the drug substance (bulk material) brought about
over time.  For the purpose of stability testing of the products described in this guideline,
such changes could occur as a result of processing or storage (e.g., by deamidation,
oxidation, aggregation, proteolysis).  For biotechnological/biological products, some
degradation products may be active.
Impurity
Any component of the drug substance (bulk material) or drug product (final container
product) that is not the chemical entity defined as the drug substance, an excipient, or
other additives to the drug product.
Intermediate
For biotechnological/biological products, a material produced during a manufacturing
process that is not the drug substance or the drug product but for which manufacture is
critical to the successful production of the drug substance or the drug product.  Generally,
an intermediate will be quantifiable and specifications will be established to determine the
successful completion of the manufacturing step before continuation of the manufacturing
process.  This includes material that may undergo further molecular modification or be
held for an extended period before further processing.
Manufacturing Scale Production
Manufacture at the scale typically encountered in a facility intended for product
production for marketing.
Pilot-Plant Scale
The production of the drug substance or drug product by a procedure fully representative
of and simulating that to be applied at manufacturing scale.  The methods of cell
expansion, harvest, and product purification should be identical except for the scale of
production.
10