The U.S. Food and Drug Administration (FDA) provides guidelines and recommendations for the validation of bioanalytical assays used in the analysis of drug substances and drug products during various stages of development and regulatory submission. These bioanalytical assays are essential for assessing the safety, efficacy, and quality of pharmaceutical products. Here's an overview of FDA's guidelines on bioanalytical assay validation:
Guidance for Industry - Bioanalytical Method Validation:
This FDA guidance provides recommendations for validating bioanalytical methods used in the analysis of drugs and biologics. It covers various types of assays, including chromatographic, ligand-binding, and cell-based assays. The guidance emphasizes key parameters and considerations for method validation, such as selectivity, sensitivity, accuracy, precision, and stability.
Critical Reagents: The FDA emphasizes the need for well-characterized critical reagents, such as reference standards, calibration standards, and quality control samples, in bioanalytical assays. These reagents play a vital role in ensuring accurate and reliable assay results.
Selectivity and Specificity: Validated bioanalytical assays should demonstrate selectivity and specificity by accurately measuring the analyte of interest in the presence of potentially interfering components. Cross-reactivity, matrix effects, and potential interferences are assessed and addressed.
Sensitivity: Bioanalytical assays should be sufficiently sensitive to detect analytes at appropriate concentrations relevant to the intended use of the assay. Lower limits of quantification (LLOQ) are established based on the precision and accuracy criteria.
Accuracy and Precision: The accuracy and precision of bioanalytical assays are crucial for reliable results. Accuracy is determined by comparing measured values with a reference standard or an accepted reference method. Precision is evaluated by assessing repeatability and intermediate precision.
Calibration and Standard Curves: Guidelines detail the proper construction and evaluation of calibration curves used to quantify analytes in samples. Calibration standards cover a range of concentrations to ensure accurate interpolation of unknown sample concentrations.
Quality Control Samples: Bioanalytical assays incorporate quality control samples at various concentration levels to assess the accuracy and precision of the assay. Acceptance criteria for the accuracy and precision of QC samples are established.
Stability: The stability of analytes and samples is evaluated under various storage conditions to ensure that assay results remain reliable over time.
Matrix Effects: Bioanalytical assays conducted in complex biological matrices (such as plasma or urine) may exhibit matrix effects that impact analyte measurement. Guidelines recommend assessing matrix effects and considering strategies to minimize their influence.
Robustness and System Suitability: The robustness of bioanalytical methods is assessed by evaluating their performance under varying conditions. System suitability criteria ensure that the assay system is functioning as expected.