Method validation is the process of proving that an analytical method is acceptable for its intended purposes.
METHOD VALIDATION = ERROR ASSESSMENT
Method validation is the process of demonstrating that analytical procedures are suitable for their intended use and that they support the identity, strength, quality, purity and potency of the drug substances and drug products
Validation: Prior ConsiderationsSuitability of Instrument Status of Qualification and Calibration Suitability of Materials Status of Reference Standards, Reagents, Placebo Lots Suitability of Analyst Status of Training and Qualification Records Suitability of Documentation Written and approved standard test procedure and proper approved protocol with pre-established acceptance criteria
Compendial vs. Non-compendial Methods
Regulatory analytical procedure in USP/NF
Non- compendial methods-Validation
Alternative analytical procedure proposed by the applicant for use instead of the regulatory analytical procedure
Spike with impurities/degradants
Show resolution and a lack of interference
Impurities/Degradants Not Available
Stress SamplesFor assay, Stressed and Unstressed Samples should be compared.
Ability of an analytical method to measure the analyte free from interference due to other components.
Selectivity describes the ability of an analytical method to differentiate various substances in a sample
Original term used in USP
Also Preferred by IUPAC and AOAC
Also used to characterize chromatographic columns
Degree of Bias (Used in USP)
The difference in assay results between the two groups
the sample containing added impurities, degradation products, related chemical compounds, placebo ingredients
Selectivity: For impurity test, impurity profiles should be compared.
Acid Hydrolysis (0.1 N HCl)
Base Hydrolysis (0.1 N NaOH)
Intent is to create 10 to 30 % Degradation
Change in the analytical procedure, drug substance, drug product, the changes, may necessitate revalidation of the analytical procedures.
“The degree of revalidation depends on the nature of the change.”
“FDA intends to provide guidance in the future on post-approval changes in analytical procedures.”
By Visual Inspection of plot of signals vs. analyte concentration
By Appropriate statistical methods
Linear Regression (y = mx + b)
Correlation Coefficient, y-intercept (b), slope (m)
Acceptance criteria: Linear regression r2 > 0.999
Requires a minimum of 6 concentration levels
Normally derived from Linearity studies.
Established by confirming that the method provides acceptable degree of linearity, accuracy, and precision.
Specific range dependent upon intended application of the procedure.