International Conference on Harmonization

Validation of Analytical Procedure

Q2(R1)

Part 1

Text on Validation of Analytical Procedures.

objective

To demonstrate that the analytical procedure is suitable for its intended use.

Types of analytical procedures to be validated

1. Identification tests2. Quantitative tests for impurities

content3. Limit tests for the control of

impurities4. Quantitative tests of the active in

samples of drug substance or drug product or the selected components in the drug product

.The objective of the analytical procedure should be clearly understood since this will govern the validation characteristics which need to be evaluated .typical validation characteristics which should be considered are listed below:•Accuracy•Precision•Repeatability• Intermediate precision

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• Specificity•Detection limit•Quantitation limit• Linearity•Range• robustnessThis should be typical for analytical procedures but occasional exceptions should be dealt with on a case-by-case basis.

Furthermore revalidation for:

•Changes in the synthesis of the drug substance•Changes in the composition of the

finished product•Changes in the analytical procedure

glossary

Analytical procedure:it is the way of performing the analysisAnd should be described in detail the steps necessary to perform each testfor sample, reference standard and reagents preparations , use of apparatus , generation of calibration curve ,etc.

specificity

The ability to assess unequivocally the analyte in the presence of componentsWhich may be expected to be present.Like: impurities , degradants , matrix .• To ensure the identity of an analyte•As a purity test•Assay (content or potency)

accuracy

Closeness of agreement between the value which is accepted and the value found.

precision

Closeness of agreement between a series of measurements obtained from multiple sampling of the same homogeneouse sample under the prescribed conditions.

Detection limit

It is the lowest amount of analyte in a sample which can be detected but not necessarily quantitated as an exact value

Quantitation limit

It is the lowest amount of analyte in a sample which can be quantitatively determined with suitable precision and accuracy.It is used for the determination of impurities and/or degradation products

linearity

it is the procedure's ability to obtain test results which are directly proportional to the concentration of analyte in the sample

range

It is the interval between the upper and lower concentration of analyte in the sample for which it has been demonstrated that the analytical procedure has a suitable level of precision , accuracy and linearity

robustness

It is a measure of procedures capacity to remain unaffected by small , but deliberate variations in method parameters and provides an indication of its reliability during normal usage.

Part 2

Validation of Analytical Procedures:Methodology

specificity

An investigation of specificity should be conducted during the validation of identification test , the determination of impurities and the assay.1. IdentificationSuitable identification tests should be able to discriminate compounds of closely related structures which are likely to be present.

.2. Assay and impurity testsFor chromatographic procedure , representative chromatograms should be used to demonstrate specificity and individual components should be appropriately labelled.To provide evidence that there is no interference from other components

.2.1.impurities are availableThis can be done by spiking pure substance with appropriate levels of impurities or/and excipients and demonstrate that the assay results is unaffected by the presence of these materials by comparison with the assay result obtained on unspiked samples.

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2.2. impurities are not availableIn this case specificity may be demonstrated by comparing the test results of samples containing impurities to a second well-characterized procedure , like pharmacopoeial method.This should include samples stored under relevant stress conditions, like light , heat , humidity, acid/base hydrolysis and oxidation

linearity

Should be evaluated by visual inspection of a plot of signals as a function of analyte concentration. If there is a linear relationship , test results should be evaluated by appropriate statistical method.For thee stablishment of linearity , a minimum of 5 concentrations is recommended.

rangeThe specified range is normally derived from linearity studies and depends on the intended application of the procedureSome of the minimum specified ranges that should be considered are :• For assay of a drug substance or drug product

;80%-120% of test concentration• For content uniformity;70%-130% of test

concentration• For dissolution testing ; +/-20% over the

specified range

accuracy1.Assay for drug substance and drug product : there are several methods of determining accuracy.2.Impurities (quantitation) :Accuracy should be assessed n samples spiked with known amount of impurities3.Recommended data :Accuracy should be assessed using a minimum of 9 determinations over a minimum of 3 concentration levels covering the specified range

precision1.Repeatability : using a min. of 9 determination covering the specified range for the procedure , or min. of 6 determination at 100% of the test concentration2.reproducibility: is assessed by means of an inter-lab trial and reproducibility should be considered in case of the standardization of an analytical procedure

Detection limit

1. Based on visual evaluation:Visual evaluation may be used for non-instrumental methods. The detection limit is by analyzing a sample with a known concentration with minimum level in which can be detected2. Based on the standard deviation of the response and the slope:DL=3.3 * std deviation of response/slope of the calibration curve

Quantitation limit1. Based on visual evaluation:For non-instrumental methods and determined by analysis of samples with known concentrations of analyte and minimum level at which the analyte can be quantified with acceptable accuracy and precision2.Based on signal-to-noise approach:It is performed by comparing measured signals from samples with known low concentration that the analyte can be quantified ; signal –to-noise ratio is 10:1.

robustnessOne consequence of the evaluation of robustness should be that a series of system suitability parameters is established to ensure that the validity of the analytical procedure is maintained whenever used.For example : different columns and ,flowrate.

Thank you

Noushin Javidvand2013