Frequently asked Questions about Analytical Method Validation
1) What is Analytical Method validation?
Ans: Analytical method validation is the documented process of ensuring a pharmaceutical analytical method is suitable for its intended use.
This is achieved by performing a series of experiments on the procedure, materials, and equipment that comprise the method being validated. The experimental results undergo statistical analysis, and a series of pre-defined acceptance criteria are applied to the results.
Establishing that the analytical method consistently produces reliable analytical results is a critical element of assuring the quality and safety of pharmaceutical products.
A validated analytical method is one has been documented as selective, accurate, precise, and linear over a stated range. Additional parameters and performance characteristics are often evaluated for methods of greater complexity. These serve to establish the method ruggedness or robustness.
Analytical method validation is a requirement for entities engaging in the testing of biological samples and pharmaceutical products for the purpose of drug exploration, development, and manufacture for human use. It also of great value for any type of routine testing that requires consistency and accuracy.
2) What Analytical Methods need to be validated?
Ans: Generally, any method used to produce data in support of regulatory (e.g., FDA, EMA) filings or the manufacture of pharmaceuticals for human use must be validated. This includes bioanalytical methods of analysis for bioavailability (BA), bioequivalence (BE), pharmacokinetic (PK), toxicokinetic (TK), and clinical studies, as well as methods used for analytical testing of manufactured drug substances and products.
According to ICH Guidelines, the following four types of methods require validation:
- Identification tests
- Quantitative tests for impurities content
- Limit tests for the control of impurities
- Quantitative tests of the active moiety in samples of drug substance or drug product or other selected component(s) in the drug product
In addition, ICH Guidelines define these four types of methods:
“Identification tests are intended to ensure the identity of an analyte in a sample. This is normally achieved by comparison of a property of the sample (e.g., spectrum, chromatographic behavior, chemical reactivity, etc.) to that of a reference standard.
Testing for impurities can be either a quantitative test or a limit test for the impurity in a sample. Either test is intended to accurately reflect the purity characteristics of the sample. Different validation characteristics are required for a quantitative test than for a limit test.
Assay procedures are intended to measure the analyte present in a given sample. In the context of this document, the assay represents a quantitative measurement of the major component(s) in the drug substance. For the drug product, similar validation characteristics also apply when assaying for the active or other selected component(s). The same validation characteristics may also apply to assays associated with other analytical procedures (e.g., dissolution).”
3) Why Analytical Methods need to be validated?
Ans: The Food and Drug Administration (FDA), European and other regulatory authorities have requirements and expectations regarding the performance and documentation of an analytical method validation.
Method validations are required when a new method is developed, an existing method is significantly modified (optimized) or an existing, validated method is applied to a different sample matrix. These methods may include HPLC, GC, GC/MS, UV-Visible, FTIR, titration, etc. Additionally, many wet chemistry (non-instrumental) methods require some level of verification or validation.
Executing validation activities is not a one-step process.
There must be assurance that "the accuracy, sensitivity, specificity, and reproducibility of test methods employed by the firm are established and documented." (CFR Title 21-Part 211).
The FDA and other regulatory authorities have cited organizations for not providing assurance that their test methods have been appropriately validated or verified. Many firms use USP methodology for routine analyses but fail to verify that the methods are "suitable for their intended use." A few examples of key regulatory findings include:
- Company A - Failure to have laboratory controls which establish scientifically sound and appropriate specifications, standards, and test procedures to assure product identity, strength, purity, and quality.
- What does this mean?
- There was no "proof" that the test methods used for product disposition decisions had been properly validated.
- Company B - "The test methods performed for Product A have not been verified to ensure suitability under actual conditions of use."
- What does this mean?
- The firm was using USP methodology without any verification of suitability.
Ans: Understand the requirements (i.e., the validation characteristics required for the sample matrix).
Ans: a) Test method is "ready" for validation.Method development should not occur at this time.
If there is a need for continued method optimization, your method is NOT ready for validation.
b) Analyst must be qualified, has demonstrated proficiency and clearly understand how to perform a method validation.
c) Instruments/Equipment is in a "qualified state."
d) materials is in qualified state (i.e samples, standards, impurities etc.. should have proper COA.)
e) protocol to be prepared and approved by concerned quality and management departments.
6) what is the difference Analytical Method validation and analytical method verification?
Ans: Method verification is the re-checking the existing validated method whether the method is suitable for particular site for inteded use.
All validation characteristics are not required for verification of a validated test method or USP compendial procedure.
7) what are the parameters commonly to be performed in analytical method verification?
Ans:
Ans:
- i. Understanding the expectation is key to a successful validation.
Ans: a) Test method is "ready" for validation.Method development should not occur at this time.
If there is a need for continued method optimization, your method is NOT ready for validation.
b) Analyst must be qualified, has demonstrated proficiency and clearly understand how to perform a method validation.
c) Instruments/Equipment is in a "qualified state."
d) materials is in qualified state (i.e samples, standards, impurities etc.. should have proper COA.)
e) protocol to be prepared and approved by concerned quality and management departments.
6) what is the difference Analytical Method validation and analytical method verification?
Ans: Method verification is the re-checking the existing validated method whether the method is suitable for particular site for inteded use.
All validation characteristics are not required for verification of a validated test method or USP compendial procedure.
7) what are the parameters commonly to be performed in analytical method verification?
Ans:
- a. Accuracy
- b. Precision
- i. Reproducibility
- ii. Repeatability
- iii. Intermediate Precision (Ruggedness)
- iv. Instrument Precision
- c. Specificity
- d. Selectivity
- e. Limit of Detection
- f. Limit of Quantitation
- g. Linearity
- h. Range
- i. Robustness
- j. Ruggedness
- a. System Suitability - Used to verify that the resolution and reproducibility of the chromatographic system are adequate for the analyses performed.
- b. Solution Stability - Determines the stability of the solution after preparation in accordance with the test method.
- i. Consideration must also be given to reagents, chemicals, mobile phase, etc.
- c. Stress Testing - Demonstrates the specificity of the assay and analytical procedures for impurities. We need to ensure that "no interference with quantitation is evident from impurities and degradants from the active ingredient and excipients."
- d. Stability indicating nature of analytical method can be proved using specificity and stress testing by showing the peak purity.
Ans:
- i. Introduction
- ii. Scope
- iii. Summary of Results
- iv. Pre-validation activity (pre-requisites)
- v. Detail of all relevant materials, chemicals, reagents, etc.
- 1. Mfr. Lot#, Purity, Expiry, etc.
- vi. Listing of all instruments/equipment
- vii. Reference Standards
- 1. Sample and Blank Preparations
- viii. Test Method Detail (may also be an attachment)
- ix. Detail of each Validation Characteristic
- 1. Data Presentation (Table Format)
- x. Protocol Exceptions (if applicable)
- xi. Copies of key representation plots, chromatograms, etc.
- xii. Representative Calculations
- xiii. Approvals
All validation activities and results should be documented in a Method Validation Summary Report and approved by Quality and Management.