Bioanalytical method validation

The fundamental components of a bioanal5dical validation (and aU validations in general) are selectivity sensitivity accuracy precision range of reliable response and linearity and reproducibility. Other characteristics of the method that should be addressed are stability carryover and control of lab contamination and matrix effects, including interferences from metabolites in incurred samples or other co-extracted compounds, as well as ionization suppression. 

The guidelines (FDA 2001) continue with a discussion of the LLOQ and state The analyte response at the LLOQ should be at least five times the response compared to a blank response , and Analyte peak (response) should be identifiable, discrete and reproducible with a precision of 20% and accuracy of 80-120% . With respect to what types of regressions are acceptable and how residual outliers should be handled in practical apphcation, the guidehnes state The simplest model that adequately describes the concentration-response relationship should be used. Selection of weighting and use of a complex regression equation should be justified. The following condition should be met in developing a calibration curve 20 % deviation of the LLOQ from nominal concentration and 15 % deviation of standards other than the LLOQ from nominal concentration. At least four out of six nonzero standards should meet the 

The FDA requirement on accuracy states (FDA 2001) Accuracy is determined by replicate analysis of samples containing known amounts of the analyte. Accuracy should be measured using a minimum of five determinations per concentration. A minimum of three concentrations in the range of expected concentrations is recommended. The mean value should be within 15 % of the actual value except at LLOQ, where it should not deviate by more than 20 %. The deviation of the mean from the true value serves as the measure of accuracy . As discussed in Section 8.4.2, such a definition implies that proportional systematic errors 

For validation studies, precision calculations are based on the same intra-day and inter-day validation QCs and runs that are used for accuracy assessment. Once again, the same rules apply in terms of the reporting and interpretation of outliers in the final report. 

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F. Garofolo, Bioanalytical method validation, in Analytical Method Validation and Instrument Performance Verification (eds. C. C. Chan, H. Lam, Y. C. Lee and X.-U. Zhang), Wiley-Interscience, Hoboken, NJ, 2004, pp. 105-138. 

Guidance for Industry, Bioanalytical method validation, US Department of Health Services, Food and Drug Administration, Center for Drug Evaluation and Research, Center for Veterinary Medicine. 

Hartmann, C., Massart, D. L., McDowell, R. D. An analysis of the Washington Conference Report on bioanalytical method validation. J. Pharm. Biomed. Anal., 12, 1994, 1337... 

U.S. Food and Drug Administration (FDA)/CDER/CVM (2001), Guidance for industry—Bioanalytical method validation, available http //www.fda.gov/cder/guidance/ index.htm. 

Bioanalytical method validation and definition of the acceptance criteria for the analytical run and/or batch... 

In the following section we summarize the current general recommendations for bioanalytical method validation practices according to the FDA guidelines, with other alternative approaches to be discussed later. 

FDA Guidance for Industry, Bioanalytical Method Validation, May 2001 (available from www.fda.gov). 

Shah, V. P. (2007). The history of bioanalytical method validation and regulation Evolution of a guidance document on bioanalytical methods validation. AAPS J. 9 E43-E47. 

A. (2000). Bioanalytical method validation A revisit with a decade of progress. Pharm. Res. 17 1551-1557. 

Guidance for industry on bioanalytical method validation availability. Federal Reg (2001) 66 28526-28527. May guidance. 

Desilva B, Smith W,Weiner R, et at. Recommendations for the bioanalytical method validation of ligand-binding assays to support pharmacokinetic assessments of macromolecules. Pharm. Res. (2003) 20 1885-1900. 

Bio analytical Methodology Bioanalytical methods for BA and BE studies should be accurate, precise, selective, sensitive, and reproducible. A separate FDA guidance entitled Bioanalytical Method Validation (May 2001) is available to assist sponsors in validating bioanalytical methods. 

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