The document discusses the expected revision of ICH Q5A guidance on viral safety of biotechnology products. Key points include: 1) ICH Q5A is being revised to address new biologic modalities like viral vectors and advances in manufacturing and detection methods. 2) The revision will provide more flexibility in viral clearance validation strategies and acceptance of alternative detection methods like PCR and HTS. 3) Challenges for viral safety of advanced manufacturing will also be discussed, as the original guidance does not address emerging approaches.

1. The life science business of Merck KGaA, Darmstadt, Germany
operates as MilliporeSigma in the U.S. and Canada.
How does the ICH Q5A
revision impact viral
safety strategy for
biologics?
Manjula Aysola
Senior Regulatory Consultant
Alison Armstrong, PhD
Global Head Technology and Scientific Solutions

2. The life science business
of Merck KGaA, Darmstadt,
Germany operates as
MilliporeSigma in the U.S.
and Canada

3. Agenda
Viral safety of biologics
ICH Q5A guidance
1
2
3
4
5
Acceptance of alternative
methods
Summary
Expected revision
and impact

4. Viral safety of
Biologics

5. ▪ Biological products include a wide range such as vaccines, blood
and blood components, allergenics, somatic cells, gene therapy,
tissues, and recombinant therapeutic proteins
▪ They are derived from natural sources or manufactured using
biotechnological processes or other cutting-edge technologies
▪ The global market for biologic therapeutic drugs should increase
from $285.5 billion in 2020 to reach $421.8 billion by 2025, at a
compound annual growth rate (CAGR) of 8.1% during the
forecast period of 2020-2025. (BCC Market Research Report, 2021)
5
Biologics constitute a large and growing global
therapeutic market

6. • Manufacturing of biologics such as monoclonal
antibodies, cell and gene therapies involves cells
• Process variability due to sensitive biological
systems
• Complex and undefined raw and starting
materials
• Risk of microbial contamination
• Global supply chain
• Increased regulatory scrutiny
6
Biologics manufacturing is complex

7. Medicinal products during their development, and prior to being marketed,
must meet strict criteria of quality, safety, and efficacy.
▪ Safety considerations associated with contaminants in biological products
include the following agents:
▪ Bacteria
▪ Fungi
▪ Mycoplasma
▪ Viruses
▪ Transmissible spongiform encephalopathies (TSE)
7
Adventitious agent contamination poses a risk to safety

8. Case Studies of Microbial Contamination in Biologic Product Manufacturing
Suvarna, K., Lolas, A., Hughes, P., Friedman, R. Biotechnology Manufacturing Team, Division of Manufacturing and
Product Quality, Office of Compliance, Center for Drug Evaluation and Research, Food and Drug Administration
Facility
Equipment
Process
Materials
Utilities
Personnel
Each source
is a potential
entry point for
microbial
contamination
Acholeplasma laidlawii (<0.2um)
Leptospira species (>5 um)
Sources of adventitious agent contamination
Minute virus of mice (MVM) ~18-24nm
8

9. 9
Adventitious Agents Contamination
Contamination of production processes do happen
“
Chiron:
Serratia marcescens
“All of Chiron's flu vaccine
deemed unsafe / FDA checks
firm's plant, says no doses can
be salvaged” 50 Million doses
scrapped.
Sabin Russell, Chronicle
Medical Writer, October 2004
Genzyme: Vesivirus 2117
“Genzyme Expects a Fine of $175
Million…$100-300 million in lost
sales.” – Pollack, Andrew.
“Genzyme Drug Shortage Leaves
Users Feeling Betrayed.” The New
York Times, April 15, 2010
GlaxoSmithKline: PCV1
“Vaccine Contamination Sparks
Fears.” – Alazraki, Melly.
“GlaxoSmithKline’s Rotavirus Vaccine
Suspended for Pig Virus
Contamination.” InvestorCenter, May
23, 2010

10. 10
Organizations with oversight on biologics
FDA
EMA
PMDA
USP
EDQM
IP
ChP
ASTM ISO ICH
PDA ISPE BioPhorum
JP
Regulatory
Agencies
Compendia
Consensus
Industry

11. ICH Q5A Guidance

12. ICH Q5A
Viral Safety Evaluation
of Biotechnology Products
Derived From Cell Lines of
Human or Animal Origin
(1997)
 The risk of viral contamination is a feature common
to all biotechnology products derived from cell lines.
 Such contamination could have serious clinical
consequences and can arise from the contamination
of the source cell lines themselves (cell substrates)
or from adventitious introduction of virus during
production.
 It is expected that the safety of these products with
regard to viral contamination can be reasonably
assured through multiple measures
Viral Safety
Assurance
12

13. Ensure safety of
raw materials
and processes
Test at
appropriate
production steps
to detect
contaminating
viruses
Implement robust
clearance strategies
Viral Safety Assurance

14. Prevent contamination of bioprocesses upstream
Ensure materials are not
contaminated by using
 Animal origin-free
 Viral mitigation treatments
 HTST
 Filtration
 Irradiation
 Cell banking under GMP
 Virus-resistant cell lines
 Well-characterized cell banks
 Single-use
 Closed systems
Starting Materials Equipment
1 2 3
Raw Materials
14

15. Multiple orthogonal measures for starting material
risk mitigation
Tiered cell
banking system
- Master cell bank
(MCB)
- Working cell bank
(WCB)
Well-characterized
cell line and
reagents
- animal-origin-free
reagents and
equipment
- Serum-free
culture medium
Extensive testing
of cell banks
• Testing of specific
viruses based on
risk
• Broad-range virus
detection by cell
culture, in vivo or
molecular
methods
Cell banks
manufactured
under GMP
2
1
4
3
15

16. 16
Remove potential contaminants from processes
▪ Assessment of Upstream and Downstream processes to remove
viruses should be carried out (Viral Clearance)
▪ Estimate quantitatively the overall level of virus reduction obtained
by the process.
▪ Studies should be carried out in a manner that is well-documented
and controlled.
▪ The reduction of virus infectivity may be achieved by removal of
virus particles or by inactivation of viral infectivity. Common
methods include:
▪ Low pH inactivation
▪ Chromatography
▪ Nanofiltration

17. 1. Viral Clearance studies are typically performed in the “downstream process”
2. The studies are performed spiking model viruses in process conditions
3. Evaluate clearance of individual steps, selected for their potential to provide viral clearance
4. Ideally, an evaluation should include steps that provide inactivation as well as removal of any
potential viral contaminants
5. At least one step should provide effective inactivation/removal of non-enveloped viruses
6. Viral clearance can only be claimed for steps that utilize independent mechanisms of
inactivation/removal
7. A sum of all the individual Log Reduction Factors (LRV) is used to calculate total reduction
Viral Clearance Studies

18. Detect
Biosafety testing is required across the entire manufacturing
process
18
Chromatography
Protein A
Bioreactor
Chromatography
Purification
Cell Line
Media and
Buffer Prep
Viral
Inactivation
Viral
Filtration
Final Fill
Cell
Expansion
Formulation
Bulk Harvest
Lot Release Testing
Drug Substance/
Final Product
Lot Release Testing
Cell Line
Characterization

19. Expected
Revision and
Impact

20. Advances
in Manufacturing
technology
Emerging or advanced
manufacturing approaches
beyond traditional unit and
batch process operations
ICH Q5A Revision is Necessary to
Address Important Advances
New biotech
products
Virus-like particles (VLPs),
subunit proteins, and viral-
vectored vaccines and gene
therapies using novel
mammalian and insect-
based vector/cell
expression systems
Virus clearance
validation strategies
Flexibility in validation
approaches should be
allowed in order to
effectively leverage
knowledge gained during
development
New and alternative
analytical
technologies for virus
detection
Nucleic acid-based assays
such as PCR and NGS may
provide rapid and sensitive
detection of adventitious
and endogenous viruses in
the starting and harvest
materials
20

21. ICH guidance development process and current status
of Q5A (as of January 2021)
Draft for
public
commenting
21
Consensus Building – Technical Document
a. ICH Parties consensus on document /
b. Draft guideline adoption by regulators
Regulatory consultation and Discussion
Adoption of an ICH harmonized
guideline
Implementation
Step
1
Step
2
Step
3
Step
4
Step
5

22. Emergence of new classes of biotechnology products
VLP vaccines
AAV Vectors
CAR-T
therapy
Stem cell
therapies
Novel
expression
systems
22
▪ Viral safety for new classes of biotechnology products (such as virus-like particles,
Novel expression systems, and Viral-vectored products) have emerged
▪ There are different risks relevant to these products
▪ For some of these, viral clearance is not feasible

23.  Nucleic acid-based assays such as Polymerase Chain Reaction (PCR) and High Throughput
sequencing (HTS) may provide rapid and sensitive detection of adventitious and endogenous
viruses in the starting and harvest materials
 Guidance to use of HTS as replacement for in vivo assays is expected
 However, these nucleic acid-based assays have limitations as they cannot distinguish
between infectious and non-infectious particles and therefore detection of a signal may need
a confirmatory test with an infectivity assay for risk-assessment
 For this reason, additional justification describing their use will be provided. Moreover,
general principles for the inclusion of new assays and potential replacement/supplement of
existing assays will be presented in order to continue to support future development of new
technology
New Virus Assays and Alternative Analytical Methods are
Available
PCR HTS
23

24. 24
High Throughput Sequencing is Now a Firmly-Entrenched
Technology in Biosafety Testing
• Unbiased, unselected analysis
• Direct identification and
adventitious agents
• Detection of Emerging viral
agents
• Significant industry interest
(AVDTIG)
• Known to regulators
• Sensitivity can be variable
• Higher complexity sample
prep and analysis
• Perhaps not fast enough for all
applications
Advantages
Challenges

25. 25
PCR technologies to detect species-specific agents
qPCR Digital PCR
• Well-accepted for specific detection
• Highly sensitive – 10GC
• Rapid
• Doesn’t discriminate live/dead
• Only detect what you are looking
for
Degenerate PCR
• Targeted to virus
families
• Identify related
unknown viruses,
e.g. MKPV and
SARS CoV-2

26. 26
Regulatory submissions have already been made, replacing
lengthy in vivo testing for well-characterized cell lines
Typical Cell Line Characterization Package
Blazar® Rodent Virus Panel, a PCR-based alternative to
antibody production test
HTS replacement,
well characterized
cells

27. 27
Traditional methods for adventitious agents testing rely on biological
amplification, which can take several weeks
Incumbent BHLRT Package Accelerated BHLRT Package
Benefits of rapid testing
• Sensitivity/ specificity
• Robustness
• Aligned to evolving
regulatory landscape
• Reduced turnaround
times
• Lower inventory costs
• Increased facility
utilisation
Greater adoption of rapid methods can speed up CMC testing

28. Alternative technologies applications
NGS/HTS remains a great technology and does have
significant application within biosafety testing
Ability to detect unknowns and support detection of
infectious virus; sensitivity remains a challenge
PCR is still the go-to-technology when rapid,
scalable results are required, and infectivity
testing cannot be performed
Limited breadth of detection
The Blazar® Platform + NGS. Addressing the delivery of
speed and breadth of detection while reducing questions
over ability to detect emerging viruses and infectivity

29. Consideration of emerging/evolving aspects of virus
clearance validation
 The recommended evaluation of
chromatographic resin at the end of its
lifetime for Protein A resin and potentially
other resins
 Additional relevant model viruses for virus
clearance studies
 Selection of appropriate model viruses for
validation of nanofilters
 Additional discussions on the virus
clearance safety margin, including
calculation of clearance factors.
 Additionally, risk mitigation technologies
for treatment of raw materials are
discussed.
− For example: Virus inactivation of raw
materials
29

30. 30
• Many viral clearance studies have been performed over the years and
industry has learned much about the mechanisms of viral inactivation and
removal in a manufacturing process.
• Currently, this knowledge has led to:
• ATSM standard that can be applied to low pH inactivation steps that meet
the criteria outlined therein.
• Clearance achieved by small parvoviruses can be applied to larger viruses
for nanofiltration.
• These claims can be used to support clinical trials for early phase
products.
• Extensive previous data suggest that clearance studies with aged Protein A
resins may not be required. This may also apply to other resins.
• In the revision to ICH Q5A, prior knowledge may allow more flexibility in
approaches to viral clearance studies.
Viral Clearance. Prior knowledge
Clearance studies will still be required to assess the impact of a
product matrix on viral reduction; this will determine whether
the product interferes with viral inactivation and removal

31. Specific challenges are associated with viral safety in advanced manufacturing are not addressed in the
original guideline and are discussed. The following challenges are discussed:
▪ Screening for and detection of adventitious and endogenous viruses during continuous manufacturing
▪ Validation of virus clearance strategies adapted from traditional unit operations
▪ Suitability of small-scale models designed for traditional virus clearance spiking studies to represent
advanced manufacturing systems
▪ Potential considerations for the role of facility design and manufacturing processes (open versus closed
systems) in viral safety evaluation (ICH Q7)
Virus clearance validation and risk mitigation strategies
for advanced manufacturing
31

32. Acceptance of
Alternative
Methods

33. 33
Risk assessment for incorporation of an alternative method
Parameter Low Medium High
Type of assay Characterization In-process Release
Technology maturity Compendial method Well-established Novel
Testing provider
Well-established testing
organization, providing GMP
quality control and inspected by
regulatory agencies
Methods and quality
systems not inspected by
regulatory agencies
Validated method Yes No
Data package available Yes, in a master file (DMF/BMF) No
Regulatory maturity
Assay used in release of
licensed product
Assay used in release
of investigational
product
Method not reviewed by
regulatory agencies
Assay comparability data
package available (where
feasible)
Yes No

34. 34
Method validation and comparability
Regulatory Expectations Alternate technologies
Alternate methods can be used Choice of method to detect a broad range of
known and emerging viruses
Method should be validated Validated in accordance global and local
regulations. Validation in accordance with ICH
Q2 (R1)
Equivalent or better than established method Meet or exceed sensitivity and specificity of the
traditional methods (Comparability)*
Fit-for-purpose Demonstrate the ability of the method to detect
potential contaminants in typical test samples
* Head-to-head comparison may not be required when substituting in vivo methods for ethical
reasons and in line with 3Rs initiatives

35. SUmmary
▪ Key developments in biologics manufacturing are driving
regulatory updates
▪ ICH Q5A on viral safety of products derived from cell lines is
undergoing revision
▪ New modalities such as viral vectored products will be in
scope
▪ Flexibility in viral clearance approaches is expected
▪ Guidance on viral safety of advanced manufacturing
paradigms is expected
▪ Guidance on implementation of detection technologies such
as PCR and HTS is expected

36. Senior Regulatory Consultant
Manjula.Aysola@milliporesigma.com
Manjula Aysola
The vibrant M, Blazar, and BioReliance are trademarks of Merck KGaA, Darmstadt,
Germany or its affiliates. All other trademarks are the property of their respective owners.
Detailed information on trademarks is available via publicly accessible resources.
© 2022 Merck KGaA, Darmstadt, Germany and/or its affiliates. All Rights Reserved.
Questions?
Alison Armstrong, Ph.D.
Global Head Technology and Scientific Solutions
Alison.Armstrong@milliporesigma.com