Bioanalytical Methods Validation for Human Studies - Pharmanet

More documents

Recommendations

Info

Draft — Not for Implementation for the development of SOPs for evaluation of an analyte’s stability in a biological matrix (Timm 1985). Whatever approach is used, the SOPs should clearly describe the statistical method and rules employed. Additional validation may include investigation of samples from dosed subjects. F. Acceptance Criteria An analytical method is considered fully validated when it meets the following criteria: Precision: The between-batch CVs for low, medium, and high concentrations should be #15%, and #20% for the LOQ QC, using a minimum of three batches. Accuracy: The between-batch mean value should be within ±15% of the nominal value at low, medium, and high QC concentrations and should not deviate by more than ±20% at the LOQ. Sensitivity: The lowest standard should be accepted as the limit of quantitation of the method if the between-batch CV at the LOQ QC is #20%. Specificity: The responses of interfering peaks at the retention time of the analyte should be less than 20% of the response of an LOQ standard. Responses of interfering peaks at the retention time of the internal standard should be #5% of the response of the concentration of the internal standard to be used in studies. Stability: Long-term, short-term, freeze and thaw, stock solution, and autosampler stability data should meet the criteria specified in the SOP. V. IN-STUDY VALIDATION Assays of all samples of an analyte in a biological matrix should be completed within the time period for which stability data are available. In general, analysis of biological samples can be done with a single determination without duplicate or replicate analysis if the assay method has acceptable variability as defined by validation data. This is true for procedures where precision and accuracy variabilities routinely fall within acceptable tolerance limits. For a difficult procedure with a labile analyte, where high precision and accuracy specifications may be difficult to achieve, duplicate or even triplicate analyses may be recommended for better estimate of analyte. j:\!guidance\2578dft.wpd 12/14/98 9
Draft — Not for Implementation A calibration curve should be generated for each analyte to assay samples in each analytical run and it should be used to calculate the concentration of the analyte in the unknown samples in the run. The spiked samples may contain more than one analyte. An analytical run could consist of either all the processed samples to be analyzed as one batch or a batch composed of processed unknown samples of one or more volunteers in a study, QC samples, and calibration standards. The calibration (standard) curve should cover the expected unknown sample concentration range in addition to a calibrator sample at LOQ. Estimation of concentration in unknown samples by extrapolation of standard curves below LOQ or above the highest standard is not recommended. Instead, the standard curve should be redefined or samples with higher concentration should be diluted and assayed (Shah 1992). All study samples from a subject should be analyzed in a single run. Once the analytical method has been validated for routine use, its accuracy and precision should be monitored regularly to ensure that the method continues to work satisfactorily. To achieve this objective, a number of separately prepared QC samples should be analyzed with processed test samples at intervals based on the total number of samples. The QC samples in duplicate at three concentrations (one near the LOQ (i.e., #3 x LOQ), one in midrange, and one close to the high end of the range) should be incorporated in each assay run. The results of the QC samples provide the basis of accepting or rejecting the run. At least four of the six QC samples should be within ±20% of their respective nominal value. Two of the six QC samples may be outside the ±20% of their respective nominal value, but not both at the same concentration (Shah 1992, Brooks 1985, Buick 1990, Mehta 1989, Ayers 1981). VI. DOCUMENTATION The validity of an analytical method should be established and verified by laboratory studies. Documentation of successful completion of such studies should be provided in the assay validation report. Protocols that define a set of specific directions that must be followed are important if the analytical results are useful for a given purpose. General and specific SOPs and good record keeping are essential parts of a validated analytical method. The analytical protocols and SOPs should be signed and dated by the laboratory director and updated regularly. The SOP should state situations under which reassay of samples is permitted. Reassays should be done in triplicate. The pre-study validation experiments, the data generated from them, and the assay quality control data should be recorded in a bound laboratory notebook. The entries should be signed by the chemist and witnessed by the laboratory supervisor. All records should be available for data audit and inspection. Documentation for pre-study validation should include: j:\!guidance\2578dft.wpd 12/14/98 10
Page 1 and 2: Guidance for Industry Bioanalytical
Page 3 and 4: Draft — Not for Implementation Ta
Page 5 and 6: Draft — Not for Implementation de
Page 7 and 8: Draft — Not for Implementation th
Page 9 and 10: Draft — Not for Implementation pe
Page 11: Draft — Not for Implementation Th
Page 15 and 16: Draft — Not for Implementation !

Bioanalytical Methods Validation for Human Studies - Pharmanet

Create successful ePaper yourself

Delete template?

Save as template?