Information guide for healthcare professionals
Biosimilars in the EU
Prepared jointly by the European Medicines Agency
and the European Commission
Table of contents
Foreword	2
Summary	3
Biological medicines: overview	 5
Key features of biological medicines	 5
Biosimilar medicines: definition and features	 8
Why biosimilars are not considered generic medicines	 10
Development and approval of biosimilars in the EU	 12
A robust regulatory framework for biosimilars	 12
Process for approval of biosimilars in the EU	 12
Data requirements for approval: a scientifically tailored package	 12
Immunogenicity	20
Extrapolation	22
Safety of biosimilars	 24
General considerations on safety for biosimilars	 24
Safety monitoring for all biological medicines, including biosimilars	 24
Traceability: importance of identifying biological medicines by tradename and batch number	 25
How healthcare professionals can help improve pharmacovigilance for biological medicines 	 26
Data included in the prescribing information and EMA assessment reports for biosimilars	 27
Data for prescribing: summary of product characteristics (SmPC)	 27
Data on biosimilarity: published in the assessment report	 27
Implications of the availability of biosimilars	 28
Interchangeability, switching and substitution: EMA and Member States’ responsibilities	 29
Definitions	 29
EMA and Member States’ responsibilities	 29
Communicating with patients on biosimilars	 30
EU contribution to the regulation of biosimilars worldwide	 31
References	32
Abbreviations	33
Glossary	34
Foreword
by Prof. Guido Rasi
EMA Executive Director
Biological medicines, often produced by cuttingedge
biotechnology, have transformed the outlook
for patients with many chronic and often disabling
conditions. An increasing number of biological
medicines are ‘biosimilars’ - medicines highly similar in
all essential aspects to an already approved biological
medicine.
The EU has pioneered the regulation of biosimilar
medicines by establishing a solid framework for their
approval and by shaping biosimilar development
globally. Since the EU approved the first biosimilar in
2006, healthcare professionals have gained increasing
experience with their use. Today, biosimilars are
an integral part of the effective biological therapies
available in the EU, supported by adequate safeguards
protecting patient safety.
As healthcare professionals are at the forefront of
patients’ care, it is vital that they have access to
reliable information on these medicines: what they
are and what scientific principles support their clinical
development, approval and safety monitoring. This
guide has therefore been prepared with the important
objective of providing healthcare professionals
with reference information on both the science and
regulation underpinning the use of biosimilars.
Contributors
This guide has been prepared by the European
Medicines Agency in collaboration with the European
Commission and scientific experts from EU Member
States.
Information needs and feedback from EU healthcare
professionals’ organisations have been sought
throughout the preparation of this document.
2	
Summary
 Since the EU approved the first biosimilar medicine (‘biosimilar’) in 2006, the EU has pioneered
the regulation of biosimilars. Over the past 10 years, the EU has approved the highest number
of biosimilars worldwide, amassing considerable experience of their use and safety.
 The evidence acquired over 10 years of clinical experience shows that biosimilars approved through
EMA can be used as safely and effectively in all their approved indications as other biological
medicines.
 A biosimilar is a biological medicine highly similar to another biological medicine already approved
in the EU (the so-called ‘reference medicine’).
 Because biosimilars are made in living organisms there may be some minor differences from the
reference medicine. These minor differences are not clinically meaningful, i.e. no differences are
expected in safety and efficacy. Natural variability is inherent to all biological medicines and strict
controls are always in place to ensure that it does not affect the way the medicine works or its safety.
 Biosimilars are approved according to the same standards of pharmaceutical quality, safety
and efficacy that apply to all biological medicines approved in the EU.
 The aim of biosimilar development is to demonstrate biosimilarity - high similarity in terms
of structure, biological activity and efficacy, safety and immunogenicity profile.
 By demonstrating biosimilarity, a biosimilar can rely on the safety and efficacy experience gained with
the reference medicine. This avoids unnecessary repetition of clinical trials already carried out with
the reference medicine.
 Demonstration of biosimilarity relies on comprehensive comparability studies with the reference medicine.
 If a biosimilar is highly similar to a reference medicine, and has comparable safety and efficacy in
one therapeutic indication, safety and efficacy data may be extrapolated to other indications already
approved for the reference medicine. Extrapolation needs to be supported by all the scientific
evidence generated in comparability studies (quality, non-clinical and clinical).
 Extrapolation is not a new concept but a well-established scientific principle used routinely when
biological medicines with several approved indications undergo major changes to their manufacturing
process (e.g. to introduce a new formulation). In most of these cases, clinical trials are not repeated for
all indications and changes are approved based on quality and in vitro comparability studies.
 All indications of biological medicines (including biosimilars) have been granted based on sound
scientific evidence.
 Safety of biosimilars is monitored through pharmacovigilance activities, in the same way as for any
other medicine. There is no specific safety requirement applicable only to biosimilars because of their
different development route.
3
 Over the last 10 years, the EU monitoring system for safety concerns has not identified any relevant
difference in the nature, severity or frequency of adverse effects between biosimilars and their
reference medicines.
 Biosimilar competition can offer advantages to EU healthcare systems, as it is expected to improve
patients’ access to safe and effective biological medicines with proven quality.
 EMA does not regulate interchangeability, switching and substitution of a reference medicine
by its biosimilar. These fall within the remit of EU Member States.
4	
Monoclonal antibody
150,000 daltons
Growth hormone
22,000 daltons
Insulin
5,808 daltons
Biological medicines: overview
Biological medicines (‘biologicals’) contain active
substances from a biological source, such as
living cells or organisms. Biological medicines are
well established in clinical practice and in many
cases they are indispensable for the treatment
of serious and chronic conditions such as diabetes,
autoimmune diseases and cancers.
Key features of biological medicines
Most biological medicines in current clinical use
contain active substances made of proteins. These
can differ in size and structural complexity, from
simple proteins like insulin or growth hormone to
more complex ones such as coagulation factors or
monoclonal antibodies (figure 1).
Biomanufacturing strictly regulated
The manufacture of biological medicines tends
to be more complex than for chemically-derived
molecules. Most biological medicines are made
by biotechnology, often using sophisticated
cell systems and recombinant DNA technology.
The EU legislation imposes strict requirements for
the manufacture of all medicines:
 EU manufacturers must hold a manufacturer’s
license and are legally obliged to comply with
Good Manufacturing Practice (GMP), the agreed
standards to obtain a medicine with proven
quality.
 National regulatory authorities in the EU
regularly inspect manufacturing sites for
compliance with GMP requirements.
 If some manufacturing steps take place outside
the EU, then non-EU manufacturers, importers
and wholesale distributors are obliged to follow
the same strict requirements and are also
regularly inspected.
For biological medicines, some of the GMP
requirements have been adapted to take
into account their specific nature (e.g. use of
appropriate aseptic techniques, refrigeration and
other storage conditions, stability, transport etc.).
Figure 1. Examples of types of proteins in biological medicines approved in the EU
5
Large molecular structure
Compared with small chemical substances,
biological medicines consist of large and often
complex molecular structures. Sophisticated
analytical methods (e.g. peptide mapping, mass
spectrometry and assays in cells) are used to study
their physicochemical and functional properties such
as molecular structure, protein modifications and
biological activity.
Inherent degree of variability
Biological medicines are made by living organisms,
which are naturally variable. Thus, the active
substance in the final biological medicine can
have an inherent degree of minor variability
(‘microheterogeneity’). This minor variability must
fall within the acceptable range to ensure consistent
safety and efficacy. This is done by adjusting the
manufacturing process to guarantee that the active
substance fits into the desired specifications range.
This degree of minor variability can be present
within or between batches of the same
biological medicine (figure 2), particularly when
manufacturing processes are modified during the
commercial life of the medicine (e.g. increasing
production scale). Strict controls are always applied
to ensure that, despite this variability, there is
batch-to-batch consistency and that the differences
do not affect safety or efficacy. In practice,
variability (within a batch or batch-to-batch) is very
low when using the same manufacturing process.
Figure 2. Example of variability between different batches of a biological medicine
Consecutive batches of the same biological medicine may show a small degree of variability (yellow
shadow) within the accepted ranges, for example in glycosylation (sugar molecules attached to the
protein, which are represented by small blue triangles). The amino acid sequence (represented by
circles) and biological activity of the protein remain the same in all batches, even when these minor
differences in sugar chains are present.
Batch 1 Batch 2 Batch 3
6
Strict control of the quality of biological
medicines
The quality of all medicines (biological and nonbiological)
approved in the EU is rigorously proven.
For biological medicines, this includes studying
their specific physicochemical properties, biological
activity, purity, sterility and stability to ensure that
all the required standards are met before batches
are released for marketing.
Potential immunogenicity
The immune system has the ability to recognise
foreign proteins and react against them. Biological
medicines usually cause no or only a limited
immune response (e.g. transient appearance of
antibodies). Adverse reactions of an immune nature
(e.g. infusion-related reactions or injection-site
reactions) are normally not severe. Rarely, however,
an immune reaction against a biological medicine
could be serious and life-threatening.
Also, antibodies directed against the biological
medicine (‘anti-drug antibodies’ or ADAs) could
neutralise the medicine’s activity and reduce its
efficacy. Thus, potential immunogenicity needs
to be always evaluated for all biological medicines.
Natural variability is inherent to
all biological medicines and strict
controls are always in place during
manufacturing to ensure that it does
not affect the way the medicine
works or its safety.
7
Biosimilar medicines: definition and features
A biosimilar medicine (‘biosimilar’) is a medicine
highly similar to another biological medicine already
marketed in the EU (the so-called ‘reference
medicine’)1, 2
. Companies can market approved
biosimilars once the period of market protection of
the reference medicine expires (after 10 years).
Since biosimilars are a type of biological medicine,
all features pertinent to biological medicines apply.
Due to the natural variability of the biological
source and to the manufacturing process unique
to each manufacturer, minor differences can occur
between the biosimilar and its reference medicine
(table 1 and figure 3). Strict controls are always in
place during manufacturing to ensure that minor
differences do not affect the way the medicine
works or its safety. Thus, these differences are not
clinically meaningful in terms of safety or efficacy.
Table 1. Specific features of biosimilar medicines
Highly similar to the
reference medicine
The biosimilar has physical, chemical and biological properties highly similar
to the reference medicine’s. There may be minor differences from the
reference medicine which are not clinically meaningful in terms of safety or
efficacy.
Noclinically meaningful
differences compared
with the reference
medicine
No differences are expected in clinical performance. Clinical studies that
support the approval of a biosimilar confirm that any differences will not
have an effect on safety and efficacy.
Variability of biosimilar
kept withinstrict limits
Minor variability is only allowed when scientific evidence shows that it does not
affect the safety and efficacy of the biosimilar. The range of variability allowed
for a biosimilar is the same as that allowed between batches of the reference
medicine. This is achieved with a robust manufacturing process to ensure that
all batches of the medicine are of proven quality.
Same strict standards
of quality, safety
and efficacy
Biosimilars are approved according to the same strict standards of quality,
safety and efficacy that apply to any other medicine.
When the active substance is a protein, both the
biosimilar and the reference medicine must contain
the same protein (i.e. amino acid sequence) and the
same ‘3D’ structure (folding of the protein). Amino
acid sequence and folding are the main factors that
determine biological activity, which must be the
same for the biosimilar and the reference medicine.
For the finished medicine, both biosimilar and
reference medicine must have the same posology
and route of administration. Some differences may
be allowed if they have no effect on safety and
efficacy - for example differences in the formulation
of the medicine (e.g. excipients), presentation (e.g.
powder to be reconstituted versus solution ready
for injection) and administration device (e.g. type of
delivery pen).
To date, the great majority of biosimilars approved in
the EU contain proteins as active substances. Table
2 lists the classes of biological medicines for which
biosimilars have been approved in the EU.
8	
Figure 3. Example of variability between a biosimilar and the reference medicine
Variability (yellow shadow) between a biosimilar and the reference medicine is comparable to what
may occur between different batches of the same biological medicine (figure 2). Minor variability, e.g.
in glycosylation (represented by small blue triangles) may be allowed, while the protein’s amino acid
sequence (circles) and biological activity are the same.
Table 2. Classes of biological medicines for which a biosimilar is currently approved in the EU
Classes of biological medicines Biosimilar approved in the EU (as at March 2017)
Polysaccharides
Low-molecular weight heparins  Enoxaparin sodium
Proteins
Growth factors  Epoetin
 Filgrastim
Hormones  Follitropin alfa
 Insulin glargine
 Somatropin (growth hormone)
 Teriparatide
Fusion proteins  Etanercept
Monoclonal antibodies  Adalimumab
 Infliximab
 Rituximab
Biosimilar medicineReference medicine
9
Why biosimilars are not considered generic
medicines
A biosimilar is not regarded as a generic of a
biological medicine. This is mostly because the
natural variability and more complex manufacturing
of biological medicines do not allow an exact
replication of the molecular microheterogeneity.
Consequently, more studies are needed for
regulatory approval of biosimilars than for generics
to ensure that minor differences do not affect safety
or efficacy. Table 3 compares development and
characteristics of generics and biosimilars.
Table 3. Comparison of development and characteristics between generics and biosimilars
Generic medicine Biosimilar medicine
Usually produced by chemical synthesis Obtained from a biological source
Generally possible to obtain exactly the same
molecule
Possible to reproduce the molecule to a
high degree of similarity due to unique
biomanufacturing methods and natural biological
variability
Mostly smaller molecules, easier to characterise In general, larger, structurally more complex
molecules, which require multiple technologies for
their characterisation
Full data requirements on pharmaceutical quality Full data requirements on pharmaceutical quality,
plus additional quality studies comparing the
structure and biological activity of the biosimilar
with the reference medicine
Development based on demonstration of
bioequivalence (i.e. that the generic and the
reference medicine release the active substance
into the body at the same rate and to the same
extent under similar conditions)
Development based on demonstration of
biosimilarity using comparability studies
(comprehensive head-to-head comparison of the
biosimilar with the reference medicine to show
high similarity in chemical structure, biological
function, efficacy, safety and immunogenicity)
10	
Generic medicine Biosimilar medicine
Clinical data requirements are mainly
pharmacokinetic bioequivalence studies
In addition to comparative pharmacokinetic and
pharmacodynamic studies, safety and efficacy
data may be required, particularly for more
complex biological medicines
All indications approved for the reference
medicine can be granted based on demonstrated
bioequivalence, without the need for further
clinical data
Efficacy and safety have to be justified in each
indication. However, confirmatory clinical trials
with the biosimilar are usually not needed in
every indication that has been approved for
the reference medicine. After demonstration
of biosimilarity, extrapolation of data to other
indications is possible if the scientific evidence
available addresses all specific aspects of these
indications
11
Development and approval of biosimilars in the EU
A robust regulatory framework
for biosimilars
Approval of medicines in the EU relies on a solid
legal framework, which in 2004 introduced a
dedicated route for the approval of biosimilars.
The EU has pioneered the regulation of biosimilars
since the approval of the first one (the growth
hormone somatropin) in 2006. Since then, the EU
has approved the highest number of biosimilars
worldwide, and consequently has the most extensive
experience of their use and safety.
Over the years, EMA has issued scientific guidelines
to help developers conform to the strict regulatory
requirements for approving biosimilars. The
guidelines have evolved to keep pace with rapid
advances in biotechnology and analytical sciences,
and they take on board increasing experience of
clinical use.
The expertise acquired over the last
10 years has enabled EU regulators
to integrate experience-based
knowledge with the initial sciencedriven
concept. This has helped
to shape current requirements for
approval.
Process for approval of biosimilars
in the EU
All medicines produced using biotechnology and
those for specific indications (e.g. for cancer,
neurodegeneration and auto-immune diseases)
must be approved in the EU through EMA (via
the so-called ‘centralised procedure’). Nearly all
biosimilars approved for use in the EU have been
approved centrally, as they use biotechnology for
their production. Some biosimilars may be approved
at national level, such as some low-molecular
weight heparins derived from porcine intestinal
mucosa.
When a company applies for marketing
authorisation at EMA, data are evaluated by EMA’s
scientific committees on human medicines and
on safety (the CHMP and PRAC), as well as by EU
experts on biological medicines (Biologics Working
Party) and specialists in biosimilars (Biosimilar
Working Party).
The review by EMA results in a scientific opinion,
which is then sent to the European Commission,
which ultimately grants an EU-wide marketing
authorisation.
Data requirements for approval:
a scientifically tailored package
Medicines are approved when studies on their
pharmaceutical quality, safety and efficacy
convincingly demonstrate that the medicine’s
benefits outweigh the risks (‘positive benefit-risk
balance’). For any biological medicine with a new
active substance, a positive benefit-risk balance
is determined mainly from evidence of safety
and efficacy in pivotal trials in humans (figure 4),
supported by solid pharmaceutical quality data and
non-clinical data.
For biosimilars, a positive benefit-risk balance
is based on demonstrating biosimilarity, i.e.
that the active substance is highly similar to the
reference medicine (figure 4). This is achieved
via comprehensive comparability studies with the
reference medicine (figure 5), and on the basis of
solid pharmaceutical quality data. By demonstrating
high similarity with the reference medicine, the
biosimilar can largely rely on the efficacy and safety
experience gained with the reference medicine.
An overview of biosimilar development compared
with the development of reference medicines is
provided in table 4.
12	
Risk management plan
Clinical studies
 Safety and efficacy
 PK/PD
 Immunogenicity
Non-clinical studies
Pharmaceutical
quality studies
Risk management plan
Comparative clinical studies
 Safety and efficacy
 PK/PD
 Immunogenicity
Comparative quality studies
Pharmaceutical
quality studies
Comparative
non-clinical studies
Reference medicine Biosimilar medicine
Figure 4. Comparison of data requirements for approval of a biosimilar versus the reference medicine
The non-clinical and clinical data
needed to approve a biosimilar are
different from those needed for a
biological medicine with a new active
substance.
This is because, by demonstrating
biosimilarity, the biosimilar relies on
the safety and efficacy experience
gained with the reference medicine.
13
Table 4. Overview of biosimilar development compared with a reference medicine
Biological medicine with new active
substance (e.g. reference medicine)
Biosimilar medicine
No previous knowledge of safety and efficacy Builds on knowledge of safety and efficacy from
years of clinical use with reference medicine
Development aims at demonstrating safety and
efficacy directly in patients
Development aims at demonstrating comparable
safety and efficacy by establishing biosimilarity
Comparability studies only for manufacturing
changes during development (e.g. producing
larger batches for clinical trials)
Comprehensive comparability studies with the
reference medicine
Full non-clinical data (pharmacology and
toxicology)
Amount of non-clinical data determined by the
outcome of quality studies
Conventional clinical trials to demonstrate efficacy
and safety in all claimed therapeutic indications
Comparative clinical trials to exclude clinically
meaningful differences
Trials designed mainly to compare with placebo
or current standard of therapy using ‘hard’
endpoints (e.g. long-term outcome, mortality,
structural damage) and a relevant patient
population to demonstrate benefit
Trials designed mainly to show clinical equivalence
with the reference medicine using sensitive
endpoints in a population where product-related
differences in clinical performance can be detected
Positive benefit-risk mainly established on the
basis of safety and efficacy studies in the intended
population
Positive benefit-risk based on demonstrating
biosimilarity (using comparability studies)
14	
Same pharmaceutical quality standards for
all medicines
Companies developing medicines in the EU,
including biosimilars, must demonstrate with
a large body of data that the medicine is
manufactured to agreed standards and that it is
suitable for its intended clinical use (what is known
as ‘pharmaceutical quality’).
The studies to prove pharmaceutical quality should
provide detailed data on:
 structural characterisation and other
physicochemical properties
 purity (traces of residues from the
manufacturing process have to be controlled
and must not exceed acceptable levels)
 biological activity
 excipients and starting materials
 strength and formulation
 the control of the manufacturing process (to
ensure that the active substance and finished
product conform with the accepted ranges for
technical specifications)
 stability of the active substance and finished
product during shelf-life under defined storage
conditions
Comparability studies: the cornerstone
of biosimilar development
Biosimilar development relies heavily on
‘comparability studies’ to establish biosimilarity
to the reference medicine. This involves a
comprehensive head-to-head comparison of the
biosimilar and the reference medicine (figure 5).
Comparability is conceived as a step-wise process
that is tailor-made for each product (figure 5);
knowledge from the initial quality comparability
studies1
(step 1) is used to determine the extent
and type of non-clinical (step 2) and clinical studies2
(step 3) required in the next step of development,
always with the aim of ruling out differences in
clinical performance between the biosimilar and the
reference medicine.
Comparability is a well-established
scientific principle of regulatory
science: comprehensive comparative
quality studies prove that
physicochemical properties and
biological activity are highly similar.
Comparative clinical and non-clinical
studies that support the approval
of a biosimilar rule out differences
which may affect the medicine’s
safety and efficacy.
15
Step 1 Comparative quality studies
In vitro studies compare the protein structure
and biological function using sensitive techniques
capable of detecting minor differences with clinical
relevance between the biosimilar and its reference
medicine. These studies are much more sensitive
than clinical trials for detecting such differences,
as there is often variability among human subjects
participating in trials. Differences that may affect
clinical safety, efficacy or immunogenicity need to
be further studied (e.g. in comparative non-clinical
or clinical studies, step 2 and 3).
Step 2 Comparative non-clinical studies
These studies include pharmacodynamic studies
in vitro, which look at binding and activation (or
inhibition) of physiological targets and immediate
physiological effects in cells. Pharmacodynamic
studies in vivo (animal models) are only done if no
suitable in vitro model exists. In vivo toxicological
studies are only required in certain cases, for
example when the biosimilar is produced in a new
type of cell or organism, or when the formulation
includes new excipients not used previously.
Step 3 Comparative clinical studies
The aim of studies in humans is not to demonstrate
safety and efficacy in patients, as these have
already been established for the reference
medicine. Clinical trials are tailored to confirm
biosimilarity and to address any questions that
may remain from previous analytical or functional
studies.
Figure 5. Biosimilar development is comparative and progresses in a step-wise manner
Comparative quality studies
 Analytical: physical + chemical properties
 Functional: biological/pharmacological activity
Comparative non-clinical studies
 Pharmacodynamic
 Toxicology
Comparative clinical studies
 Pharmacokinetic/pharmacodynamic
 Efficacy + safety + immunogenicity
Step1
Step2
Reference medicine Biosimilar medicine
Step3
16
Approval of biosimilars builds on
existing scientific knowledge on safety
and efficacy of the reference medicine
gained during its clinical use, so fewer
clinical data are needed.
From a scientific and regulatory
point of view, the reference
medicine’s entire clinical development
programme does not need to be
repeated. This means that patients
and healthy volunteers will not be
subjected to unnecessary clinical
trials.
Comparability: a scientific principle routinely
used after manufacturing changes to
medicines on the market
Comparability is not a new regulatory concept, but
a well-established scientific principle that has been
used for decades in the manufacture of medicines
made by biotechnology3, 4, 5
. Companies producing
biological medicines are likely to adapt or improve
the manufacturing process several times during
the commercial life of a product (e.g. by increasing
production scale). Comparing batches before and
after a manufacturing change ensures consistency,
so that there are no changes in safety or efficacy.
A change to the manufacturing process must
always be approved by regulators. The extent
of the comparability studies required following a
manufacturing change to a biological medicine will
depend on the expected impact on quality, safety
and efficacy of the medicine. Most often, analytical
and functional data are sufficient, and clinical trials
to prove safety and efficacy are not needed (table
5, scenario 1 and 2). Clinical trials are needed only
if an impact on safety and efficacy is anticipated
(scenario 3).
Table 5. Comparability studies needed following changes to the manufacturing process of a medicine
produced by biotechnology
Type of manufacturing change Expected impact Comparability studies needed
1. Minor change (e.g. adding
a more sensitive test method
to characterise the active
substance)
Does not affect the
pharmaceutical quality of the
medicine (no impact on product
specifications)
Limited physicochemical studies
comparing batches before and
after the change
2. Significant change (e.g.
changes to the cell system used
to produce the active substance)
May affect product
characteristics or specifications
but not expected to affect safety
or efficacy
Comprehensive physicochemical
and functional in vitro studies
3. Major change (e.g. certain
changes in the medicine’s
formulation)
May possibly affect safety or
efficacy
Comprehensive physicochemical
and in vitro functional studies
complemented as needed by
non-clinical and clinical studies
17
Most of the widely used biological
medicines on the market have
seen several changes to their
manufacturing process and these
often result in minor differences from
the version initially approved or the
version used in the clinical trials filed
for approval.
Regulators have built up extensive
experience to conclude that such
differences do not affect the
medicine’s quality, safety and
efficacy.
Comparative trials are designed to confirm
biosimilarity and clinical performance
Comparison of the biosimilar with the reference
medicine involves extensive comparability studies to
assess any possible impact on safety and efficacy.
The approach is equivalent to when major changes
are introduced to the manufacturing process for
a medicine made by biotechnology (scenario 3 in
table 5).
Clinical trials for biosimilars do not
need to include all the pivotal studies
conducted for the reference medicine
to prove safety and efficacy in
humans.
Comparative clinical trials are
specifically designed to rule out
clinically relevant differences in
safety or efficacy between the
biosimilar and the reference
medicine, and to confirm
biosimilarity.
There are certain key aspects that need to be
considered for the design of comparative clinical
trials:
 The goal is to rule out potential product-related
differences that could affect pharmacokinetics
(PK), efficacy or safety, including
immunogenicity.
 PK studies should be conducted in a
homogeneous and sensitive population (healthy
volunteers or patients) to detect any possible
differences between the biosimilar and its
reference medicine. Healthy volunteers can be
selected if they represent the most appropriate
population to detect such differences and if the
medicines’ toxicity is not a cause of concern.
 To compare the pharmacological effects, a
sensitive endpoint that allows detection of
product-specific differences should be chosen.
 Endpoints measuring pharmacodynamic activity
(‘PD endpoints’) can be used when available
and when relevant for the medicine’s clinical
effect. In many settings, these endpoints are
more sensitive than clinical outcomes to detect
potential differences between a biosimilar
and the reference medicine. PD endpoints are
usually based on laboratory tests. Examples
include:
 glucose infusion rate in a glucose clamp
study for biosimilar insulins (rather
than measures of HbA1c or long-term
consequences of diabetes)
 absolute neutrophil count for biosimilar
granulocyte-colony stimulating factor
(rather than number of serious infections)
 number of oocytes retrieved during in
vitro fertilisation for biosimilar folliclestimulating
hormone (rather than
pregnancies or live births)
 If there are no suitable PD endpoints, a clinical
efficacy trial comparing the biosimilar and
its reference medicine is generally needed.
This trial should be adequately powered,
randomised, parallel-group, preferably doubleblind,
and should use efficacy endpoints. These
18	
endpoints should preferably measure the
pharmacological activity of the medicine and be
less influenced by patient- or disease-related
factors.
 Adequate equivalence margins should be chosen
for the primary efficacy endpoint. Margins
are established on the basis of knowledge of
efficacy with the reference medicine, as well as
on clinical judgement. Equivalence margins are
set specifically for the indication studied and
depend on the endpoint chosen. They should
represent the largest difference in efficacy
that would not matter in clinical practice;
treatment differences within this range would
thus be acceptable because they have no
clinical relevance. The principles of selecting
equivalence margins are not unique to biosimilar
testing: they are routinely used in clinical trials
when comparing treatment alternatives, or
when comparing the same medicine before and
after manufacturing changes that may have a
clinical effect3
.
 As for all clinical trials, legal requirements (e.g.
Good Clinical Practice) have to be met.
The extent of clinical studies needed for approval
depends on several factors, including those outlined
in table 6.
Table 6. Factors affecting the number and types of clinical studies to be carried out for approval
Determining factor Reason for varying amount/type of data
Complexity of the molecule and comparability
data available
For simpler molecules with well-established action
(e.g. filgrastim) and where comparative quality
data are solid, it may be sufficient to compare the
effect of the biosimilar and reference medicine
with PK and PD studies in healthy volunteers.
For larger molecules (e.g. monoclonal
antibodies), even when robust quality and in vitro
comparability data are provided, a comparative
study in patients using a conventional clinical
efficacy endpoint is usually required.
Availability of a PD endpoint which correlates with
efficacy
Conventional clinical efficacy endpoints are
generally not needed if the PD endpoint correlates
with clinical benefit.
Safety concerns with the reference medicine or
pharmacological class
Safety data are collected throughout the clinical
development programme, including during PK and
PD studies. The amount of data normally depends
on the type and severity of the safety concerns
identified for the reference medicine. In principle,
adverse reactions related to the pharmacological
action can be expected at similar frequency for
the biosimilar and reference product, if functional,
analytical, PK, PD and efficacy comparability data
are robust.
 19
Determining factor Reason for varying amount/type of data
Potential for immunogenicity Analytical studies are the first step in assessing
potential for immunogenicity. To complement this,
clinical data on immunogenicity are generally
required; animal studies are of limited value in
predicting immune response in humans.
Possibility of extrapolating to other indications Indications of the reference medicine can be
approved for the biosimilar in the absence of
specific clinical data generated with the biosimilar
(‘extrapolation of indications’). This can be
accepted if all the scientific evidence available
from the comparability studies establishes
biosimilarity and can address the specific
aspects of the ‘extrapolated’ indication (e.g.
mode of action, potentially unique safety or
immunogenicity aspects).
Extrapolation of data to other indications is always
supported by robust physicochemical and in vitro
studies to assess all the possible mechanisms of
action.
Immunogenicity
Immunogenicity is always studied for biological
medicines6, 7
. This is because of the intrinsic ability
of proteins and other biological medicines to cause
an unwanted immune response, which, in rare
cases, could cause a serious adverse reaction (e.g.
anaphylaxis or delayed hypersensitivity) or reduced
efficacy.
Key considerations on potential
immunogenicity of biological medicines
Although immunogenicity could be a potential
concern for all biological medicines, there are
several important considerations:
Immunogenicity is not a safety concern
in itself
Severe reactions due to an increased immune
response are very rare and most often an immune
response against a biological medicine is not
associated with clinical consequences (e.g. antidrug
antibodies could be transient).
The nature of immune reactions depends
on many factors
Immunogenicity may be influenced by product
characteristics (e.g. changes to the structure of
the protein may occur during improper storage
or transport, or proteins could form aggregates),
but also by treatment-related factors (e.g. the risk
may vary with subcutaneous versus intravenous
administration or with continuous versus
intermittent treatment regimen) and patient- or
20	
disease- related factors (e.g. age, genetic and
immune status or concomitant treatments).
Harmful immunogenicity is unlikely after
manufacturing changes or after switching
Many biological medicines are intended for longterm
management of chronic conditions, and
therefore, over time the patient may receive
biological medicines with slight differences.
Experience shows that a harmful immune response
is unlikely after a change to the manufacturing
process of a biological medicine, since comparability
studies prove that the batch from the new process
is of the same quality and free of impurities or
aggregates that can trigger immunogenicity8
.
There is also no reason to believe that harmful
immunogenicity should be expected after switching
between highly similar biological medicines8
.
Immunogenicity is always monitored post-
marketing
Immunogenicity of biological medicines is always
monitored by regulatory authorities once the
medicine is on the market. This is particularly
important to learn of rare immune reactions that
can only be detected after a long follow-up period in
larger numbers of patients.
Immunogenicity data needed for approval
of a biosimilar
Clinical immunogenicity studies are generally
required for biological medicines. In the case of
monoclonal antibodies they are always required,
as it is more difficult to predict the incidence of
unwanted immunogenicity, the characteristics of
the immune response or the clinical consequences.
Such studies look both at short-term immune
responses (e.g. infusion-related reactions), as well
as long-term (e.g. delayed responses due to an
evolving immune reaction).
Immunogenicity data required for approval
include incidence, titre and persistence of
antibodies against the biological medicine (ADAs),
neutralisation assays (because neutralising
antibodies may reduce the effect of the medicine),
assessment of the clinical impact and measures to
manage the potential risk of immunogenicity (e.g.
special monitoring of immune-mediated adverse
reactions or use of concomitant medication to
mitigate infusion reactions).
In general, the amount and type of data will depend
on several factors, including:
 the type of biological medicine and its intended use
 product characteristics: the great majority
of immunogenicity studies focus on how
differences at product level may affect an
immune response. These include studying
changes to the structure or minor variability
in the protein (microheterogeneity), or
how protein aggregation could occur due to
components derived from the formulation or
packaging.
 previous knowledge of immunogenicity: for
biological medicines with a low immunogenicity
profile (e.g. filgrastim), patients are usually
tested for antibodies frequently at the
beginning and at the end of the clinical study
with a shorter follow-up period and routine
pharmacovigilance measures to manage any
potential risk. In cases where clinically relevant
immunogenic responses have been observed
(e.g. epoetins) immunogenicity testing is more
frequent, there is a longer patient follow-up
with intensified clinical monitoring, and specific
post-marketing studies may be required.
21
Extrapolation
If a biosimilar is highly similar to a reference
medicine and has comparable safety and efficacy
in one therapeutic indication, safety and efficacy
data may be extrapolated to other indications
approved for the reference medicine. This means
that fewer clinical trials or no trials at all need to be
carried out with the biosimilar in certain indications.
Extrapolation of data to other indications is always
supported by scientific evidence generated in robust
comparability studies (quality, non-clinical and
clinical).
Extrapolation is a well-established scientific principle
which has been used for many years9
, for example
whenever a biological medicine with several
approved indications undergoes major changes to
its manufacturing process (e.g. new manufacturing
site or development of new formulations). The
potential effect of these changes on the biological
medicine’s clinical performance is carefully
evaluated with comparability studies (mainly quality
and in vitro studies). If clinical studies are needed,
these are conducted in one relevant indication and,
based on all these data, extrapolation to the other
indications is usually possible.
Extrapolation is not a new concept
but a well-established scientific
principle used routinely when
biological medicines with several
approved indications undergo major
changes to their manufacturing
process.
In most of these cases, regulators
approve manufacturing changes
based on comparability studies and
clinical trials are not repeated for all
indications.
Criteria for extrapolation
Important considerations need to be borne in
mind before an indication for a biosimilar can be
approved based on extrapolated safety and efficacy
data. These include:
Mechanism of action
The mechanism of action of the active substance
should be mediated by the same receptor(s) in both
the initial and the extrapolated indication.
If the mode of action of the active substance
is complex and involves multiple receptors or
binding sites (as is often the case with monoclonal
antibodies), it may be difficult to establish the
contribution of each receptor or binding site to each
indication. In this case, additional studies (nonclinical
or clinical) will be needed to prove that
the biosimilar and reference medicine will behave
similarly in the extrapolated indication.
Relevant study population
Comprehensive comparability studies must
show that the biosimilar is highly similar to the
reference medicine (by means of safety, efficacy
and immunogenicity data) in a key indication in a
population in which potential differences in clinical
performance can be detected.
Extrapolation across different clinical settings
Data from a given indication (e.g. rheumatoid
arthritis) may not be directly applicable in terms
of safety or efficacy to an indication falling within
another therapeutic area where the mode of action,
posology or pharmacokinetics may be different (e.g.
oncology). In this case, additional studies may be
needed.
22	
Extrapolation of safety data
Safety data can only be extrapolated after a
comparable safety profile has been established
for the biosimilar in one therapeutic indication. If
comparability is shown at structural, functional,
pharmacokinetic and pharmacodynamic level, and
efficacy is comparable, then adverse reactions due
to the biosimilar’s pharmacological action can be
expected to be the same and to occur at similar
frequencies.
Extrapolation of immunogenicity data
Extrapolation of immunogenicity data is not
automatic, as it always requires justification.
This is because immunogenicity is determined
by more than product-related characteristics.
Factors relating to patients (age, immune status),
disease (comorbidities, concomitant treatments) or
treatment-related factors (route of administration,
length of exposure) also have to be considered.
The scientific criteria for
extrapolation of efficacy and safety
data are supported by over 10 years
experience of safe and effective use
of biosimilars in the EU.
Extrapolation is also supported by
regulators’ extensive experience
in the routine evaluation of
manufacturing changes for
biologicals, most often without the
need to repeat clinical studies in all
indications.
Prescribers can have confidence
in using biological medicines
(including biosimilars) for all their
approved indications, as all approved
indications of a medicine are granted
based on scientific evidence.
23
Safety of biosimilars
General considerations on safety
for biosimilars
Since the introduction of the first biosimilar in
clinical use in 2006, an increasing number of
biosimilars have been approved and safely used in
the EU.
Apart from reactions of an immunological nature,
most adverse drug reactions (ADRs) can be
predicted from the pharmacological action, and
occur with both the reference medicine and the
biosimilar (e.g. high haemoglobin levels with
epoetins). Of more than 25 biosimilars approved
in the EU to date, none has been withdrawn or
suspended for reasons of safety or efficacy.
Over the last 10 years, the EU
monitoring system for safety
concerns has not identified any
relevant difference in the nature,
severity or frequency of adverse
effects between biosimilar medicines
and their reference medicines.
Safety monitoring for all biological
medicines, including biosimilars
A robust regulatory framework to protect
patients’ safety
The EU has a well-established system for
monitoring, reporting, assessing and preventing
adverse drug reactions for all medicines, including
all biological medicines. Authorities continuously
evaluate the benefit-risk balance of all medicines
and take necessary regulatory action (e.g.
introducing new warnings in the product information
or restricting use) to safeguard public health.
Same safety monitoring for all biological
medicines
Safety monitoring of biosimilars follows the
same requirements that apply to all biological
medicines10
. There is no specific requirement just
for biosimilars.
A plan to manage risks always in place
Companies applying for marketing authorisation
in the EU must submit a risk management plan
(RMP) for each new medicine, including biological
medicines. The RMP, which is tailored for each
product, includes a pharmacovigilance plan and risk
minimisation measures to identify, characterise and
minimise a medicine’s important risks. The RMP of
a biosimilar is based on knowledge and experience
gained with the reference medicine.
For all medicines approved in the EU, in addition
to the conditions of use in the product information,
additional measures (e.g. educational brochures,
patient alert cards or inclusion of patients in
registries) may be needed to manage a specific
risk. When any extra measure is applied to the
reference medicine (e.g. educational material), it
should also be considered for the biosimilar.
Safety studies after marketing
Post-marketing studies allow monitoring of known
risks and also permit detection of rare adverse drug
reactions that emerge only when large numbers of
patients have been treated for a long period. This is
why at the time of approval regulators may impose
on the company an obligation to carry out a postauthorisation
safety study (PASS). This also binds
the company to register the study in the publicly
available EU PAS Register: http://www.encepp.eu/
encepp_studies/indexRegister.shtml.
24	
The criteria for deciding whether a post-marketing
safety study is needed are the same for all
medicines, including biosimilars and their reference
medicines. If a PASS has been requested for a
reference medicine, it will normally be requested
also for the biosimilar.
Collecting spontaneous adverse drug reactions
and submitting PSURs
As for all medicines, companies marketing
biosimilars must collect all reports of suspected
adverse drug reactions and submit periodic safety
update reports (PSURs) to regulators. Regulatory
authorities review reports for any signal suggestive
of a possible unwanted effect. If a signal is
suspected, it is evaluated by EMA’s scientific
committees, which will determine if any action is
needed.
Additional monitoring and black triangle
All new medicines are closely monitored after being
introduced to the market. Biological medicines
approved after 1 January 2011 are subject to socalled
‘additional monitoring’ and are included in
a list of medicines under ‘additional monitoring’.
This list includes medicines authorised in the EU
that are being monitored particularly closely by
regulatory authorities, for example because the
active substance is new to the market or there are
limited data on its long-term use. In this case, they
are monitored particularly closely during the first
years after approval.
The black triangle symbol identifies medicines under
additional monitoring. It is displayed in the SmPC
and package leaflet together with the sentence:
“This medicinal product is subject to additional
monitoring”
Additional monitoring encourages healthcare
professionals and patients to report any suspected
adverse drug reactions of new medicines. This
enables prompt identification and analysis of
information about the medicines to add to the
knowledge gained during clinical trials. If a
biological medicine (or biosimilar) is labelled with
a black triangle, it does not necessarily mean that
there are additional safety concerns with it.
Monitoring long-term or long-latency adverse
events
Safety monitoring of long-term or long-latency
events for biological medicines follows the same
principles as for small-molecule medicines.
However, detecting and characterising the longterm
adverse drug reactions of biological medicines
may be difficult using only spontaneous reporting.
This is why additional pharmacovigilance activities
(such as including patients in registries) could be
required in certain cases.
Traceability: importance of
identifying biological medicines by
tradename and batch number
An important requirement for the safety monitoring
of all biological medicines is the need for product
and batch traceability during clinical use and at all
levels in the supply chain10
. This covers the time
from release by the manufacturer and progress
through the entire distribution chain until the
medicine is administered to the patient.
As required by EU law, every medicine will have
an invented name (tradename or brand name)
together with the active substance name (i.e. the
25
international nonproprietary name, or INN, which is
assigned by WHO).
For identifying and tracing biological medicines
in the EU, medicines have to be distinguished
by the tradename and batch number and this
is particularly important in cases where more
than one medicine with the same INN exists on
the market. This ensures that, in line with EU
requirements for ADR reporting, the medicine can
be correctly identified if any product-specific safety
(or immunogenicity) concern arises.
Healthcare professionals play an essential role in
contributing to the understanding of a medicine’s
safety profile during clinical use. Biological
medicines are approved on the basis of an
acceptable safety profile and they should be used
according to the recommendations in the summary
of product characteristics (SmPC) and package
leaflet. If a suspected ADR is identified for a
biological medicine, healthcare professionals should
report it, taking care to include the tradename and
batch number of the medicine. It is important that
healthcare professionals report any suspected ADR
of a biosimilar even if the reaction is already listed
in the reference medicine’s SmPC.
For a biological medicine, its tradename, INN
and batch number can be found in the product
packaging. A statement has been introduced in the
SmPC to remind healthcare professionals of the
need to clearly record the tradename and batch
number in the patient’s healthcare records.
How healthcare professionals can
help improve pharmacovigilance
for biological medicines:
 It is important that the
medicine’s tradename and
batch number are recorded
by healthcare professionals at
all levels, including dispensing
and patient administration.
 Prescribers should include the
tradename of the medicine in
the prescription.
 Healthcare professionals
should ensure that tradename
and batch number are reported
in case of suspected adverse
drug reactions, according to
local practice and national
regulations.
 In cases where the product
is dispensed at a community
pharmacy, the tradename and
batch number of the biological
medicine should be provided to
the patient.
 If a patient is switched from
one biological medicine to
another with the same active
substance, it is important to
record the tradename and
batch number for each of the
medicines.
 Healthcare professionals
should contact their national
medicines regulatory
authorities for advice on
how to report adverse drug
reactions.
26	
Data included in the prescribing information and
EMA assessment reports for biosimilars
Data for prescribing: summary of
product characteristics (SmPC)
The EU SmPC includes information and
recommendations to enable healthcare
professionals to prescribe the medicine and to give
advice to patients on its use.
Section 5.1 (pharmacodynamic properties) of the
SmPC will identify a medicine as a biosimilar with
the following wording:
[Brand name] is a biosimilar medicinal product.
Detailed information is available on the website
of the European Medicines Agency http://www.ema.
europa.eu.
In the EU, the SmPC of a biosimilar is aligned with
that of the reference medicine. The biosimilar’s
SmPC mentions the name of the active substance
(i.e. INN) and not the tradename of the reference
medicine. Details of the studies with the biosimilar
as well as the tradename of the reference medicine
can be found in EMA’s assessment report, available
on EMA’s website.
A biosimilar can be approved for some or all of the
authorised indications of the reference medicine,
as a company may choose not to apply for all
the reference medicine’s indications. Healthcare
professionals should check that the biosimilar is
authorised for the intended indication.
When a company does not apply for all the
indications of the reference medicine, efficacy
data on the additional indications are not included
in the biosimilar’s SmPC, however safety data
are reflected.
Data on biosimilarity: published in
the assessment report
For each medicine approved through EMA, including
biosimilars, EMA publishes a group of documents
known as the european public assessment report
(‘EPAR’). In addition to the EU product information
(SmPC, package labelling and package leaflet), the
EPAR documents contain assessment reports on the
scientific evaluation of the medicine at the time of
approval and when major changes are introduced
(e.g. when a new indication is added).
Details of how each biosimilar was developed
and on the comparability studies to demonstrate
biosimilarity are given in their assessment
reports. These include information on analytical
and functional comparability, pharmacokinetics,
clinical comparability and immunogenicity. Where
applicable, the assessment report also includes the
scientific rationale for extrapolation of data.
Over 25 biosimilars have been approved through
EMA for use in the EU as at April 2017. Their
assessment reports can be accessed on EMA’s
website, on the landing page of each medicine,
under the tab ‘assessment history’.
27
Implications of the
availability of biosimilars
Once the period of market protection of the reference
medicine expires (usually 10 years), companies can
market approved biosimilars. In general, it is expected
that biosimilars will be introduced to the market at a
lower price than their reference medicine. Thus, they
are expected to be less costly for healthcare systems
in the EU. This is partly due to a tailored development
programme that builds on scientific knowledge gained
with the reference medicine and so avoids unnecessary
repetition of non-clinical and clinical studies. It can
also be due to increased market competition.
The experience over the past 10 years11
indicates
that biosimilar competition can offer advantages to
EU healthcare systems, as having more treatment
alternatives available is expected to improve
patients’ access to biological medicines with proven
pharmaceutical quality.
28	
Interchangeability, switching and substitution:
EMA and Member States’ responsibilities
Definitions
In the context of biosimilars and reference
medicines, it is important for healthcare
professionals to be aware of the terminology to
refer to interchangeability and substitution practices
in the EU.
Interchangeability refers to the possibility of
exchanging one medicine for another medicine that
is expected to have the same clinical effect. This
could mean replacing a reference product with a
biosimilar (or vice versa) or replacing one biosimilar
with another. Replacement can be done by:
 Switching, which is when the prescriber
decides to exchange one medicine for another
medicine with the same therapeutic intent.
 Substitution (automatic), which is the practice
of dispensing one medicine instead of another
equivalent and interchangeable medicine
at pharmacy level without consulting the
prescriber.
EMA and Member States’
responsibilities
When EMA carries out the scientific review of
a biosimilar, the evaluations do not include
recommendations on whether the biosimilar is
interchangeable with the reference medicine,
and thus whether the reference medicine can be
switched or substituted with the biosimilar.
The decision on whether to allow interchangeable
use and substitution of the reference biological
medicine and the biosimilar is taken at national
level. Information on the scientific evaluation
performed by EMA’s scientific committees is
available on EMA’s website and could be used to
support decisions.
In the EU, prescribing practices and advice to
prescribers fall under the responsibility of Member
States, which have the necessary legal framework
in place and issue regulations, guidelines and advice
in their areas of competence. As for any medicine,
healthcare professionals should choose carefully
when prescribing, taking into account the patient’s
medical history.
For questions on prescribing
or interchangeability practices,
information may be available at the
national competent authority in the
relevant Member State (the list can
be found on EMA’s website).
Any decision on switching should
involve the prescriber in consultation
with the patient, and take into
account any policies that the country
might have regarding the prescribing
and use of biological medicines.
 29
Communicating with
patients on biosimilars
If patients have questions on whether a particular
biological medicine is a biosimilar, their healthcare
professionals can find this information in section
5.1 of the SmPC. The package leaflet, which contains
key recommendations for patients on how to use
the medicine properly, does not include mention of
biosimilarity, as this only refers to the medicine’s
development route and is not related to the use of the
medicine.
If patients receiving biosimilars in a clinical setting
(e.g. in hospital) want information on their biosimilar,
they can ask their healthcare professionals for the
package leaflet. Alternatively, they can download it
from EMA’s website.
For questions from patients on what is a biosimilar,
and how its safety and efficacy are ensured, patients
can consult a questions-and-answers document12
in
patient-friendly language available on the European
Commission’s website.
When a new medicine is approved by EMA, the
Agency also publishes a summary for the general
public explaining why the medicine is approved in
the EU. These summaries (called ‘EPAR summaries’),
are available on each medicine’s landing page
on EMA’s website in the form of questions-andanswers
documents in all official EU languages.
EPAR summaries for biosimilars can be accessed
by searching for the medicine’s name on EMA’s
homepage. Alternatively, a live list of EPAR summaries
for all biosimilars can be found on EMA’s website.
Several national regulatory authorities also provide
information on biosimilars in their local language.
30	
EU contribution to the
regulation of biosimilars
worldwide
The EU’s regulation of biosimilars has shaped
biosimilar development globally, by establishing the
core principles that underpin biosimilar development in
other highly regulated areas of the world.
The requirements for biosimilar approval in the US by
the FDA are based on the same scientific rationale as
in the EU, although specific data requirements may
differ between these two regions due to different legal
frameworks. Other international regulators such as
Australia’s TGA directly apply the principles set out in
the EU legislation for the development and approval of
biosimilars.
The World Health Organization (WHO) has developed
its own guidelines for biosimilars (called ‘similar
biotherapeutic products’ or SBPs) and biosimilar
monoclonal antibodies, with the aim of providing
guidance to regulatory agencies worldwide. These
WHO guidelines incorporate many of the scientific
principles used by EMA and its scientific committees
in EU guidelines, as EU experts have been closely
involved in the preparation of the WHO guidelines.
EMA continues to share the extensive experience
gained in the EU on biosimilars with other regulators
around the world and participates in a number
of international forums such as the International
Pharmaceutical Regulators Forum.
31
References
1. European Medicines Agency: Similar biological
medicinal products (overarching guideline).
CHMP/437/04 Rev. 1. http://www.ema.europa.
eu/docs/en_GB/document_library/Scientific_
guideline/2014/10/WC500176768.pdf. Accessed on
6 March 2017.
2. European Medicines Agency: Similar biological
medicinal products containing biotechnologyderived
proteins as active substance: non-clinical
and clinical issues. EMEA/CHMP/BMWP/42832/2005
Rev. 1. http://www.ema.europa.eu/docs/en_GB/
document_library/Scientific_guideline/2015/01/
WC500180219.pdf. Accessed on 6 March 2017.
3. Weise M, Bielsky MC, De Smet K, et al.
Biosimilars: what clinicians should know. Blood
2012;120(26):5111-7.
4. European Medicines Agency: ICH Q5E
Biotechnological/biological products subject
to changes in their manufacturing process:
comparability of biotechnological/biological products.
CPMP/ICH/5721/03. http://www.ema.europa.
eu/docs/en_GB/document_library/Scientific_
guideline/2009/09/WC500002805.pdf. Accessed on
6 March 2017.
5. European Medicines Agency: Comparability
of biotechnology-derived medicinal products
after a change in the manufacturing process
- non-clinical and clinical issues. EMEA/CHMP/
BMWP/101695/2006. http://www.ema.europa.
eu/docs/en_GB/document_library/Scientific_
guideline/2009/09/WC500003935.pdf. Accessed on
6 March 2017.
6. European Medicines Agency: Immunogenicity
assessment of biotechnology-derived therapeutic
proteins. EMEA/CHMP/BMWP/14327/2006. http://
www.ema.europa.eu/docs/en_GB/document_
library/Scientific_guideline/2009/09/WC500003946.
pdf. Accessed on 6 March 2017.
7. European Medicines Agency: Immunogenicity
assessment of monoclonal antibodies intended for
in-vivo clinical use. EMA/CHMP/BMWP/86289/2010.
http://www.ema.europa.eu/docs/en_GB/document_
library/Scientific_guideline/2012/06/WC500128688.
pdf. Accessed on 6 March 2017.
8. Kurki P, van Aerts L, Wolff-Holz E, et al.
Interchangeability of biosimilars: a European
perspective. BioDrugs 2017;31:83-91.
9. Weise M, Kurki P, Wolff-Holz E, et al.
Biosimilars: the science of extrapolation. Blood
2014;124(22):3191-6.
10. European Medicines Agency: Guideline on good
pharmacovigilance practices (GVP), Product- or
Population-Specific Considerations II: Biological
medicinal products. EMA/168402/2014. http://
www.ema.europa.eu/docs/en_GB/document_
library/Scientific_guideline/2016/08/WC500211728.
pdf. Accessed on 14 March 2017.
11. IMS Health, The impact of biosimilar
competition, June 2016. http://ec.europa.eu/
growth/tools-databases/newsroom/cf/itemdetail.
cfm?item_id=8854. Accessed on 10 April 2017.
12. European Commission: What I need to know
about biosimilar medicines. Information for
patients. 2016. http://ec.europa.eu/growth/tools-
databases/newsroom/cf/itemdetail.cfm?item_
id=9066. Accessed on 6 March 2017.
32	
Abbreviations
ADA Anti-drug antibody
ADR Adverse drug reaction
BMWP Biosimilar Working Party (EMA’s working party of EU experts on biosimilars)
CHMP Committee for Medicinal Products for Human Use (EMA’s scientific committee
formed by EU experts who review and recommend marketing approval)
DNA Deoxyribonucleic acid
EMA European Medicines Agency
EPAR European public assessment report
EU PAS Register EU post-authorisation study register
FDA Food and Drug Administration (the US medicines regulatory authority)
GMP Good manufacturing practice
INN International nonproprietary name
PASS Post-authorisation safety study
PD Pharmacodynamic(s)
PK Pharmacokinetic(s)
PRAC Pharmacovigilance and Risk Assessment Committee (EMA’s scientific
committee formed by EU experts on safety of medicines)
PSUR Periodic safety update report
RMP Risk management plan
SBP Similar biotherapeutic products (WHO term for biosimilars)
SmPC Summary of product characteristics (the EU prescribing information)
TGA Therapeutic Goods Administration (Australia’s medicines regulatory authority)
WHO World Health Organisation
33
Glossary*
Anti-drug antibody Antibodies produced by the body’s immune system against an active
substance (particularly a large molecule, such as a protein). ADAs against
a medicine can result in loss of efficacy or in immunological reactions.
Adverse drug reaction An unwanted medical event following the use of a medicine. Suspected ADRs
are those that have been reported to authorities but which are not necessarily
caused by the medicine.
Bioequivalence When two medicines release the same active substance into the body
at the same rate and to the same extent under similar conditions.
Biosimilarity Demonstration of high similarity to a reference biological medicine in
terms of chemical structure, biological activity and efficacy, safety and
immunogenicity profile, mainly based on comprehensive comparability
studies.
Biotechnology Technology that relies on biological systems, living organisms or components
from living organisms (such as genes or enzymes) to make a specific product.
A medicine obtained by biotechnology often has been produced by inserting
a gene into cells so that they can produce the desired protein.
Centralised procedure Approval process of medicines which involves a single application,
a single evaluation and, for successful applications, a single authorisation
valid throughout the European Union. It is mandatory for certain types
of medicines, including all medicines produced by biotechnology and
medicines for specific conditions such as cancer, neurodegeneration and
autoimmune diseases.
Comparability Head-to-head comparison of a biosimilar with its reference medicine to rule
out any significant differences between them in terms of structure and
function. This scientific principle is routinely used when a change is introduced
to the manufacturing process of medicines made by biotechnology, to ensure
that the change does not alter safety and efficacy.
Extrapolation Extension of the efficacy and safety data from a therapeutic indication
for which the biosimilar has been clinically tested to another therapeutic
indication approved for the reference medicine.
Glycosylation Modification of a protein after its production, which involves the addition
of carbohydrate (sugar) groups. Depending on the amount and type of sugar
groups added, the biological activity can change.
* The definitions included in this document and in the glossary are descriptions, not regulatory definitions.
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INN International nonproprietary name, a unique name that identifies active
substances. The list of INNs, which is globally recognised and public property,
is maintained by WHO.
Interchangeability Refers to the possibility of exchanging one medicine for another medicine that
is expected to have the same clinical effect.
Microheterogeneity Minor molecular variability among biological substances due to natural
biological variability and slight alterations to production methods.
Pharmacodynamic
studies
Studies of the biochemical and physiological effects of a medicine in the body,
including mechanism of action.
Pharmacokinetic
studies
Studies of how a medicine is processed by the body, including its absorption,
distribution, biotransformation and excretion.
Pharmacovigilance Activities to detect and assess adverse reactions and other effects
of medicines in use.
Periodic safety update
report
Report that a company marketing medicines in the EU must submit
to regulatory authorities periodically (e.g. every six months) that includes
new reports of suspected adverse drug reactions.
Post-translational
change
Modification of a protein after its production, which involves the attachment
of molecules or groups such as phosphates or carbohydrates (sugars).
Recombinant DNA
technology
Technology that involves combining sequences of DNA that do not occur
naturally, for example inserting a gene for producing a therapeutic protein.
Reference medicine A biological medicine approved in the EU, which is chosen by a company
developing a biosimilar as a reference for the head-to-head comparison of
quality, safety and efficacy.
Specifications Acceptance limits for important quality standards which an active substance
or a finished medicine must meet.
Substitution Practice of dispensing one medicine instead of another equivalent and
interchangeable medicine at pharmacy level without consulting the prescriber.
Switching When the prescriber decides to exchange one medicine for another medicine
with the same therapeutic intent.
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This guide was last updated on 27 April 2017
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© European Medicines Agency, 2017.
Reproduction is authorised provided the source is acknowledged.
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