1. 1
Risk-Based Analytical Method Validation and
Maintenance Strategies
Stephan O. Krause, Ph.D.
Principal Scientist, Regulatory Science, Development
MedImmune
PDA/PCMO Task Force Leader for Analytical Methods and IMP Specifications

2. 2
The Late-Stage Analytical Method Lifecycle: Risk-based
Validation and Maintenance Strategies
Agenda:
 Part 1
 AMV - Readiness Assessment Process
 Risk-Based AMV Study Designs and Acceptance Criteria
 Parts 2-3
 Analytical Method Replacement (AMR)
 Analytical Method Maintenance (AMM)
 Part 3
 The Analytical Method Transfer (AMT) Process
Krause/PDA, 2012

3. 3
The Analytical Method Life Cycle
Krause/PDA, 2012

4. 4
Example of Assessment Process of AMV Readiness
Krause/PDA, 2012

5. 5
General AMV Risk Assessment Strategy
The purpose of risk assessment(s) for AMV studies is to provide
measurable results for:
1) The desired amount of formal validation studies to be executed.
2) The level of method performance needed as manifested in the AMV
protocol acceptance criteria.
Krause/PDA, 2012

6. 6
Points to Consider in Overall Risk Assessment
for Analytical Methods
Points to Consider Examples Expected Potential Risk/Impact
Method type and
intended use (Identity,
Safety, Purity, Quality,
Potency, and Stability)
a. Safety test: Sterility test using
new rapid microbial method.
b. Quality test: Excipient
concentration at final production
stage.
a. Purity/Stability test:
Degradation products during
storage.
a. Potential risk to patients and firm is high if
sterility test provides false negative results.
b. Potential risk to patients is relatively low if the
quality test provides inaccurate results as
excipient is quantitatively added during
production.
c. Potential risk to patients is high if stability test
is incapable to measure all degradation products.
Surrogate and/or
complementary
method is routinely
used
Purity/Safety test: A HPSEC
method is used for quantitation of
protein aggregate levels. A second
electrophoresis method provides
similar results for aggregate levels.
If second method routinely supports the results
of the primary method, the risk to patients may
be lower if the primary method provides
inaccurate results.
Production Process
Stage
Purity Test: Fermentation
impurities are measured before
purification and after purification.
Early-stage inaccurate impurity results from less
reliable test method are lower risk to patients if
late-stage testing provides more accurate results.
Analytical Platform
Technology (APT)
Purity test: APT HPSEC method is
used to test in-process samples.
Current QC experience with this method
performance should lower the risk to patient
and/or firm if the effect of different sample types
is insignificant.

7. 7
The Six General AMQ Classes and Prospective AMQ
Studies
AMQ Class Description
Typical Risk /
Uncertainty Level
(1=Low, 5=High)
Suggested Prospective
AMQ StudiesAMQ
Class No.
Analytical Method
Product /
Process Sample
A New New 4-5 Full Qualification
B New Old 3-4
Full Qualification Plus
Bridging Studies
C
Analytical Platform
Technology (not
qualified “as run”)
New 2-3 Partial Qualification
D
Analytical Platform
Technology
(qualified)
New 1-2
Partial Qualification or
Verification
E
Analytical Platform
Technology
(qualified)
Modified
(Formulation,
Conc.)
1-2 Verification
F Compendial New 1-2
Verification per USP
<1226>

8. 8
The Five General AMV Classes and Prospective
AMV Studies
AMV Class Description
Typical Risk /
Uncertainty Level
(1=Low, 5=High)
Suggested Prospective
AMV Studies
AMV
Class
No.
Analytical Method
Product /
Process Sample
A New New 4-5 Full Validation
B New Old (Validated) 3-4(1) Full Validation Plus
AMR(2)
Studies
C
Analytical Platform
Technology (not
validated “as run”)
New 2-3 Partial Validation
D Old (Validated) New 1-2
Partial Validation or
Verification
E Compendial New 1-2
Verification per USP
<1226>
(1) If a new analytical method (forced method replacement) is needed due to supply reasons, the risk level can be generally considered higher
because no other option may exist. Unforced test method replacements can be considered to be a lower risk level as more time may be available
to optimize the method performance.
(2) AMR = Analytical Method Replacement. A study to confirm that a new analytical method can perform equally or better than the existing one.
From Krause, PDA/DHI 2007.

9. 99
FACenter for Biologics Evaluation &
ResearchFDA
Safety
Methods
Validated
Qualified
Methods
Validated
Methods Re-Validation
(as needed)
Replacement
(Supplement)
Selection
Design
Development
Optimization
Life Cycle of Analytical MethodsLife Cycle of Analytical Methods
Phase 1 Phase 2Discovery/Pre-clinical Phase 3 BLA Post-Licensure
Performance
Characteristics
Robustness

10. 10

11. CQA Development, CMC Changes, Specifications
11

12. 12
Analytical Method Lifecycle – Intended Use

13. 13
Risk-Based AMV Protocol Acceptance Criteria
Krause/PDA, 2012

14. 14
Analytical Method Replacement (AMR) Categories
from ICH E9 (and USP <1033> for Equivalence)
 Equivalence
 Non-inferiority
 Superiority
Krause/PDA, 2012

15. 15
Analytical Method Replacement
Suggested Performance Comparison Characteristics and Statistics
ICH Q2(R1)
Category
Identification
Test
(Qualitative)
Limit Test
(Qualitative)
Limit Test
(Quantitative)
Potency or
Content (Purity
or Range)
(Quantitative)
Accuracy Not Required Not Required TOST; Some
Data could be at
QL level
TOST
Intermediate
Precision
Not Required Not Required ANOVA, mixed
linear model, or
other variance
component
analysis
ANOVA, mixed
linear model, or
other variance
component
analysis
Specificity Probability
and/or Chi-
Squared for
Number of
Correct
Observations
Probability and/or
Chi-Squared for
Number of Correct
Observations
Not Required Not Required
Detection
Limit
Not Required Depends on how
DL was
established.
Probability
calculations may
be used
Not Required Not Required
Krause/PDA, 2012

16. 16
Demonstrating Equivalence
Krause/PDA, 2012

17. 17
Demonstrating Non-Inferiority
Krause/PDA, 2012

18. 18
Demonstrating Superiority
Krause/PDA, 2012

19. 19
Demonstrating Equivalence
Simplified Case Study
Because of anticipated supply problems for critical SDS-PAGE materials, it
was decided to develop and validate a capillary zone electrophoresis (CZE)
method that will replace the current (licensed) electrophoretic method.
The method performance characteristics for a quantitative limit test,
accuracy and intermediate precision, are compared.
For accuracy:
A delta of plus/minus 1.0% was chosen for the equivalence category
between both impurity levels. The 1.0% difference limit was set because a
future result difference of 1.0% is still acceptable within the existing release
and stability specifications (acceptable patient and mfger’s risks).
Both methods were run simultaneously (side-by-side) for each of a total of
n=30 reported results were compared by two-sided matched-paired t-test
statistics with pre-specified equivalence limits of plus/minus 1.0% (% =
reported percent and not relative percent).
Krause/PDA, 2012

20. 20
Demonstrating Equivalence
Results
Equivalence Test Results Comparing Current Method to CZE:
Sample Size (n): 30
Hypothesized Difference in Mean: 0%
Minus Delta: -1.0%
Plus Delta: +1.0%
SDS-PAGE Mean (n=30): 3.8%
CZE Mean (n=30): 5.1%
90% confidence interval of CZE results (vs. SDS-PAGE): 4.88-5.32%
Krause/PDA, 2012

21. 21
Equivalence of New Method Not Demonstrated
(New method’s result are different)
Krause/PDA, 2012

22. 22
Analytical Method Maintenance (AMM)
VMP for Analytical Methods
AMC AMM
AMV
Process Map Steps
Method Modifications Method Review
Critical Method Elements
Standards and Controls Critical Reagents
Software/Computer Analytical Instrumentation
Statistical Data Reduction New/Additional Operator
Emergency Reviews
(OOS, many invalids)
Periodic Reviews
(Short and Long Term)
Quarterly or Annual Reviews Extensive Reviews
Prospective Retrospective
Krause, 2005.

23. 23
AMM - Continuous Review Example:
Combining Laboratory and Manufacturing Control Charts
88
92
96
100
104
108
112
0 10 20 30 40 50 60
Sequential Batches Tested (last n=60)
Potency(inunits/mL)
SPC
Assay Control
Upper Specifications
Lower Specifications
SPC Mean
(101.0 units/mL)
Assay Control
Mean
(99.0 units/mL)
Krause/PDA/DHI, 2007.

24. 24
AMM - Simplified Example:
Extensive Method Performance Evaluation
Krause/PDA/DHI, 2007.
AMV and Method Performance Verification Checklist Results Comments
Test Method Number/Title/Revision:
Process Step/Product Sampling Point(s):
Most Recent Validation/Verification Date:
Specifications Supported:
ICH Q2(R1) Test Method Category:
Suitable Overall Performance Demonstrated in AMV Report ?
Changes to Test System After AMV Studies ?
If yes, provide more information:
Number of Valid Test Runs Over Last 12 Months
Number of Invalid Test Runs Over Last 12 Months
Calculate Invalid Rate/Percentage:
Current System Control Limits (ex., 3 Standard Deviations):
Test System in Control ?
Method Performance Acceptable ?
If no, provide more information:
QC Signature:
QA Signature: