Nonclinical Dose Formulation: Out of Specification Investigations

Nonclinical safety studies are required to follow applicable Good Laboratory Practice (GLP) regulations. Nonclinical dose formulations are required to be analyzed to confirm the analyte concentration, homogeneity, and stability. Analytical samples that fall outside of the acceptance criteria are considered out of specification (OOS), and an investigation should be conducted. The US FDA has issued a guidance document for GMP studies on conducting OOS investigations. However, no regulatory guidance has been issued regarding nonclinical safety study (GLP) OOS investigations, which often vary in regard to content, assessment, and impact statements. There is opportunity to improve the quality of OOS investigations by defining expectations and providing guidance in several areas including root cause assessment, impact statements, and acceptable paths forward. This paper will provide recommendations of best practices for nonclinical dose formulation OOS investigations.     

Specific Method Validation and Sample Analysis Approaches for Biocomparability Studies of Denosumab Addressing Method and Manufacture Site Changes

Manufacturing changes during a biological drug product life cycle occur often; one common change is that of the manufacturing site. Comparability studies may be required to ensure that the changes will not affect the pharmacokinetic properties of the drug. In addition, the bioanalytical method for sample analysis may evolve during the course of drug development. This paper illustrates the scenario of both manufacturing and bioanalytical method changes encountered during the development of denosumab, a fully human monoclonal antibody which inhibits bone resorption by targeting RANK Ligand. Here, we present a rational approach to address the bioanalytical method changes and provide considerations for method validation and sample analysis in support of biocomparability studies. An updated and improved ELISA method was validated, and its performance was compared to the existing method. The analytical performances, i.e., the accuracy and precision of standards and validation samples prepared from both manufacturing formulation lots, were evaluated and found to be equivalent. One of the lots was used as the reference standard for sample analysis of the biocomparability study. This study was sufficiently powered using a parallel design. The bioequivalence acceptance criteria for small molecule drugs were adopted. The pharmacokinetic parameters of the subjects dosed with both formulation lots were found to be comparable.     

Small Molecule Specific Run Acceptance,Specific Assay Operation,and Chromatographic Run Quality Assessment: Recommendation for Best Practices and Harmonization from the Global Bioanalysis Consortium Harmonization Teams

Consensus practices and regulatory guidance for liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) assays of small molecules are more aligned globally than for any of the other bioanalytical techniques addressed by the Global Bioanalysis Consortium. The three Global Bioanalysis Consortium Harmonization Teams provide recommendations and best practices for areas not yet addressed fully by guidances and consensus for small molecule bioanalysis. Recommendations from all three teams are combined in this report for chromatographic run quality, validation, and sample analysis run acceptance.KEY WORDS: bioanalytical assay validation, LC-MS/MS, sample analysis, small molecule     

药物安全性评价研究中供试品的检测与分析

供试品的检测与分析是保证药物非临床安全性评价结果可靠性的关键性因素。本文从药物安全性评价中供试品的含量检测方法验证、取样分析、含量准确性分析、稳定性分析、均匀性分析、分析结果和超标准结果的处理、剩余样品的处理等方面进行了讨论,并提出作者的看法。     

Statistical Considerations for Assessment of Bioanalytical Incurred Sample Reproducibility

Bioanalytical method validation is generally conducted using standards and quality control (QC) samples which are prepared to be as similar as possible to the study samples (incurred samples) which are to be analyzed. However, there are a variety of circumstances in which the performance of a bioanalytical method when using standards and QCs may not adequately approximate that when using incurred samples. The objective of incurred sample reproducibility (ISR) testing is to demonstrate that a bioanalytical method will produce consistent results from study samples when re-analyzed on a separate occasion. The Third American Association of Pharmaceutical Scientists (AAPS)/Food and Drug Administration (FDA) Bioanalytical Workshop and subsequent workshops have led to widespread industry adoption of the so-called “4–6–20” rule for assessing incurred sample reproducibility (i.e. at least 66.7% of the re-analyzed incurred samples must agree within ±20% of the original result), though the performance of this rule in the context of ISR testing has not yet been evaluated. This paper evaluates the performance of the 4–6–20 rule, provides general recommendations and guidance on appropriate experimental designs and sample sizes for ISR testing, discusses the impact of repeated ISR testing across multiple clinical studies, and proposes alternative acceptance criteria for ISR testing based on formal statistical methodology.     

Historical perspective on the development and evolution of bioanalytical guidance and technology

Bioanalytical methods employed for the quantitative determination of drugs and their metabolites in biological fluids provide essential regulatory data for bioavailability, bioequivalence, pharmacokinetic and toxicokinetic studies. The quality of these studies is directly related to the underlying bioanalytical data. Data generated by a typical bioanalytical laboratory is submitted to not only the local regulatory agency, but also to multiple regulatory agencies worldwide. Many pharmaceutical companies and CROs are now performing bioanalytical work for global submissions and the regulatory agencies are often reviewing the bioanalytical work performed in other countries. The bioanalytical workplace has become global and therefore needs universal rules for quality and compliance of bioanalysis. This paper provides a historical perspective and insight into the development and evolution of the regulatory guidance for bioanalytical method validation and analysis of samples.     

Best practices during bioanalytical method validation for the characterization of assay reagents and the evaluation of analyte stability in assay standards, quality controls, and study samples

Characterization of the stability of analytes in biological samples collected during clinical studies together with that of critical assay reagents, including analyte stock solutions, is recognized as an important component of bioanalytical assay validation. Deficiencies in these areas often come to light during regulatory inspections. Best practices, based on current regulatory guidance, for the assessment of these issues as they pertain to ligand binding and chromatographic assays are covered in this review. Additionally, consensus recommendations reached during the recent AAPS/FDA Workshop on bioanalytical assay validation are highlighted.     

Aspects of bioanalytical method validation for the quantitative determination of trace elements

Bioanalytical methods are used to quantitatively determine the concentration of drugs, biotransformation products or other specified substances in biological matrices and are often used to provide critical data to pharmacokinetic or bioequivalence studies in support of regulatory submissions. In order to ensure that bioanalytical methods are capable of generating reliable, reproducible data that meet or exceed current regulatory guidance, they are subjected to a rigorous method validation process. At present, regulatory guidance does not necessarily account for nuances specific to trace element determinations. This paper is intended to provide the reader with guidance related to trace element bioanalytical method validation from the authors' perspective for two prevalent and powerful instrumental techniques: inductively coupled plasma-optical emission spectrometry and inductively coupled plasma-MS.     

Key elements of bioanalytical method validation for macromolecules

The Third American Association of Pharmaceutical Scientists/US Food and Drug Administration (FDA) Bioanalytical Workshop, which was held May 1 and 2, 2006, in Arlington, VA, addressed bioanalytical assays that are being used for the quantification of therapeutic candidates in support of pharmacokinetic evaluations. One of the main goals of this workshop was to discuss best practices used in bioanalysis regardless of the size of the therapeutic candidates. Since the last bioanalytical workshop, technological advancements in the field and in the statistical understanding of the validation issues have generated a variety of interpretations to clarify and understand the practicality of using the current FDA guidance for assaying macromolecular therapeutics. This article addresses some of the key elements that are essential to the validation of macromolecular therapeutics using ligand binding assays. Because of the nature of ligand binding assays, attempts have been made within the scientific community to use statistical approaches to interpret the acceptance criteria that are aligned with the prestudy validation and in-study validation (sample analysis) processes. We discuss, among other topics, using the total error criterion or confidence interval approaches for acceptance of assays and using anchor calibrators to fit the nonlinear regression models.     

Recommendations for the Bioanalytical Method Validation of Ligand-Binding Assays to Support Pharmacokinetic Assessments of Macromolecules

PURPOSE: With this publication a subcommittee of the AAPS Ligand Binding Assay Bioanalytical Focus Group (LBABFG) makes recommendations for the development, validation, and implementation of ligand binding assays (LBAs) that are intended to support pharmacokinetic and toxicokinetic assessments of macromolecules. METHODS: This subcommittee was comprised of 10 members representing Pharmaceutical, Biotechnology, and the contract research organization industries from the United States, Canada, and Europe. Each section of this consensus document addresses a specific analytical performance characteristic or aspect for validation of a LBA. Within each section the topics are organized by an assay's life cycle, the development phase, pre-study validation, and in-study validation. Because unique issues often accompany bioanalytical assays for macromolecules, this document should be viewed as a guide for designing and conducting the validation of ligand binding assays. RESULTS: Values of +/- 20% (25% at the lower limit of quantification [LLOQ]) are recommended as default acceptance criteria for accuracy (% relative error [RE], mean bias) and interbatch precision (%coefficient of variation [CV]). In addition, we propose as secondary criteria for method acceptance that the sum of the interbatch precision (%CV) and the absolute value of the mean bias (%RE) be less than or equal to 30%. This added criterion is recommended to help ensure that in-study runs of test samples will meet the proposed run acceptance criteria of 4-6-30. Exceptions to the proposed process and acceptance criteria are appropriate when accompanied by a sound scientific rationale. CONCLUSIONS: In this consensus document, we attempt to make recommendations that are based on bioanalytical best practices and statistical thinking for development and validation of LBAs.     

Advances in validation, risk and uncertainty assessment of bioanalytical methods

Bioanalytical method validation is a mandatory step to evaluate the ability of developed methods to provide accurate results for their routine application in order to trust the critical decisions that will be made with them. Even if several guidelines exist to help perform bioanalytical method validations, there is still the need to clarify the meaning and interpretation of bioanalytical method validation criteria and methodology. Yet, different interpretations can be made of the validation guidelines as well as for the definitions of the validation criteria. This will lead to diverse experimental designs implemented to try fulfilling these criteria. Finally, different decision methodologies can also be interpreted from these guidelines. Therefore, the risk that a validated bioanalytical method may be unfit for its future purpose will depend on analysts personal interpretation of these guidelines. The objective of this review is thus to discuss and highlight several essential aspects of methods validation, not only restricted to chromatographic ones but also to ligand binding assays owing to their increasing role in biopharmaceutical industries. The points that will be reviewed are the common validation criteria, which are selectivity, standard curve, trueness, precision, accuracy, limits of quantification and range, dilutional integrity and analyte stability. Definitions, methodology, experimental design and decision criteria are reviewed. Two other points closely connected to method validation are also examined: incurred sample reproducibility testing and measurement uncertainty as they are highly linked to bioanalytical results reliability. Their additional implementation is foreseen to strongly reduce the risk of having validated a bioanalytical method unfit for its purpose.     

Validation of immunoassay for protein biomarkers: bioanalytical study plan implementation to support pre-clinical and clinical studies

Biomarkers have emerged as an important tool to optimize the benefit/risk ratio of therapeutics. The scientific impact of biomarker studies is directly related to the quality of the underlying data. It is therefore important that guidance be established for validation of assays used to support drug development. This paper specifically focuses on validation of immunoassay for protein biomarker to support pre-clinical and clinical studies. Therapeutics (small- and macro-molecules) and their respective target/ligand are out of scope. This paper describes the implementation of a bioanalytical study plan for the validation of immunoassays to support decision-making biomarkers and biomarker selection during preclinical and clinical studies. It establishes the complete operating procedure as well as the parameters and their respective acceptance criteria and defines milestones and decision points to be followed during the assay validation that should result in high quality bioanalytical data in a limited timeframe and with reduced costs. The bioanalytical study plan can be applied to the validation of a wild range of immunoassay technology such as monoplex ELISA, automated analyzer, multiplex assays or cutting edge technology. Before any validation, a feasibility study is performed to assess the performance of the immunoassay using biological samples which should mimic the clinical population. The feasibility study addresses the likelihood that an assay will be able to achieve its intended purpose with parallelism being the most critical element (milestone 1). At the end of the feasibility study, a decision is taken to either continue with the validation or change the assay (milestone 2). The milestone 3 consists of the establishment of the nominal value of quality control to be used during the validation. The quality controls used to validate an assay should preferentially be prepared using neat (non-spiked) biological matrix (ideally derived from the specific trial population). The last milestone (milestone 4), the formal validation, includes demonstration of the assay performance meeting accuracy and precision acceptance criteria within (intra-run) and between (inter-run) validation runs for each QC sample. Validation also includes the assessment of stability of the protein biomarker in the biological matrix. It is recognized that the extent of the validation should be correlated to the intended use of the data and the assay acceptance criteria should take into consideration the study objective(s), nature of the methodology and the biological variability of the biomarker.     

Recommendations and Best Practices for Reference Standards and Reagents Used in Bioanalytical Method Validation

The continued globalization of pharmaceutics has increased the demand for companies to know and understand the regulations that exist across the globe. One hurdle facing pharmaceutical and biotechnology companies developing new drug candidates is interpreting the current regulatory guidance documents and industry publications associated with bioanalytical method validation (BMV) from each of the different agencies throughout the world. The objective of this commentary is to provide our opinions on the best practices for reference standards and key reagents, such as metabolites and internal standards used in the support of regulated bioanalysis based on a review of current regulatory guidance documents and industry white papers for BMV.     

Recommendations for the validation of immunoassays used for detection of host antibodies against biotechnology products

Most biological drug products elicit some level of anti-drug antibody (ADA) response. This antibody response can, in some cases, lead to potentially serious side effects and/or loss of efficacy. In humans, ADA often causes no detectable clinical effects, but in the instances of some therapeutic proteins these antibodies have been shown to cause a variety of clinical consequences ranging from relatively mild to serious adverse events. In nonclinical (preclinical) studies, ADA can affect drug exposure, complicating the interpretation of the toxicity, pharmacokinetic (PK) and pharmacodynamic (PD) data. Therefore, the immunogenicity of therapeutic proteins is a concern for clinicians, manufacturers and regulatory agencies. In order to assess the immunogenic potential of biological drug molecules, and be able to correlate laboratory results with clinical events, it is important to develop reliable laboratory test methods that provide valid assessments of antibody responses in both nonclinical and clinical studies. For this, method validation is considered important, and is a necessary bioanalytical component of drug marketing authorization applications. Existing regulatory guidance documents dealing with the validation of methods address immunoassays in a limited manner, and in particular lack information on the validation of immunogenicity methods. Hence this article provides scientific recommendations for the validation of ADA immunoassays. Unique validation performance characteristics are addressed in addition to those provided in existing regulatory documents pertaining to bioanalyses. The authors recommend experimental and statistical approaches for the validation of immunoassay performance characteristics; these recommendations should be considered as examples of best practice and are intended to foster a more unified approach to antibody testing across the biopharmaceutical industry.     

A comprehensive method validation strategy for bioanalytical applications in the pharmaceutical industry--2. Statistical analyses.

The first paper in this two-part series described [Lang and Bolton, J. Pharm. Biomed. Anal. 9, 357-361 (1991)] an overall validation strategy for bioanalytical methods. This second paper focuses on the statistical analyses performed on the validation data that will allow the analyst to evaluate the reliability and reproducibility of a bioanalytical method. Based on the validation results, acceptance criteria for the quality control concentrations are established and used during the study proper to determine if the analytical run is valid. After analysing the clinical study samples and accepting the analytical runs, the quality control results are incorporated into databases to update their acceptance limits. This continuous validation process enables the analyst to monitor the method's performance over time and be confident that accurate sample concentrations are being reported. It is important to emphasize that the statistical analyses of the data provide information that should be considered from a practical point of view by the analyst. The analyst should use sound judgement in evaluating the reliability of the method.     

Criteria for selecting pharmacokinetic repeat study samples

The pharmacokinetic (PK) repeat study sample, selected by the study pharmacokineticist, requires repeat bioanalysis because the concentration is incongruous with drug plasma concentration versus time profile. The inconsistency could be due to a number of reasons, including the detectable drug concentration in a predose sample or a sample from a placebo control group or a significant double peak in the terminal phase of an individual plasma concentration versus time profile that is not consistent with the profiles from other subjects in the same dose group. The justification for selecting the PK repeat sample should be clearly documented. The repeat analysis should be conducted in duplicate or triplicate as allowed by sample volume. To avoid subjectively selecting PK repeat samples, standard operating procedures should be prepared prior to the start of the study in order to define the criteria for selecting PK repeat study samples and also the procedure for conducting repeat analysis and reporting repeat assay values. The incurred sample re-analysis (ISR) assessment and the repeat analysis of pharmacokinetically anomalous samples are different in terms of purpose and conduct; the ISR assessment alone cannot accept or reject the results from a study for analytical reasons. Therefore, the results from the ISR assessment for assuring the reliability and reproducibility of a validated bioanalytical method in animal or human plasma or other biological matrices should not be used to substitute the results of repeat analysis of pharmacokinetically anomalous samples from a nonclinical or clinical study.     

AMS method validation for quantitation in pharmacokinetic studies with concomitant extravascular and intravenous administration

A technique has emerged in the past few years that has enabled a drug's intravenous pharmacokinetics to be readily obtained in humans without having to conduct extensive toxicology studies by this route of administration or expand protracted effort in formulation. The technique involves the intravenous administration of a low dose of (14)C-labelled drug (termed a tracer dose) concomitantly with a non-labelled extravascular dose given at therapeutically levels. Plasma samples collected over time are analysed to determine the total parent drug concentration by LC-MS (which essentially measures that arising from the oral dose) and by LC followed by accelerator mass spectrometry (AMS) to determine the (14)C-drug concentration (i.e., that arising from the intravenous dose). There are currently no published accounts of how the principles of bioanalytical validation might be applied to intravenous studies using AMS as an analytical technique. The authors describe the primary elements of AMS when used with LC separation and how this off-line technique differs from LC-MS. They then discuss how the principles of bioanalytical validation might be applied to determine selectivity, accuracy, precision and stability of methods involving LC followed by AMS analysis.     

New Frontiers—Accelerator Mass Spectrometry (AMS): Recommendation for Best Practices and Harmonization from Global Bioanalysis Consortium Harmonization Team

The technique of accelerator mass spectrometry (AMS) is applicable to the analysis of a wide range of trace elemental isotopes. However, in the context of the pharmaceutical industry, it is invariably used to measure radiocarbon (¹⁴C). There are two broad modes of application: analysis of total ¹⁴C sometimes termed “direct AMS” and analysis of specific ¹⁴C-labelled analytes in a variety of matrices following some method of isolation. It is the latter application which is within the remit of the GBC team, and the team has made efforts to propose harmonized recommendations for the validation of AMS when used in a regulatory bioanalytical mode, i.e. the quantification of specific analyte(s) using liquid chromatography with off-line detection by AMS now known as “LC + AMS”. The GBC team has reached a position where they have agreed to many aspects, but also differ on some aspects of what constitutes a bioanalytical assay validation in support of clinical studies using this technology. The detail of most of this will be covered under separate publication(s), but for the purposes of this paper, we have outlined the points of consensus. The purpose of this article is not to provide a roadmap for validation of LC + AMS assays, but to highlight agreements amongst the industry representative experts and the practitioners, as well as identifying specific areas essential for establishing assay quality but where additional discussion is required to reach agreement.     

Setting acceptance criteria for validation of analytical methods of drug eluting stents: Minimum requirements for analytical variability

Accuracy and reliability of the analytical results are crucial for ensuring quality, safety and efficacy of drug eluting stents (DESs). Method validation is the process used to confirm that the analytical procedure employed for a specific test is suitable for its intended use. Results from method validation can be used to judge the quality, reliability and consistency of analytical results. Validation of analytical methods includes the identification of the performance parameters relevant for the given procedure, the definition of appropriate acceptance criteria and the appropriate design of the validation studies. Achieving an appropriate consideration of the analytical variability in assay procedures and setting acceptance criteria for analytical validations is however much more difficult than usually described. Criteria which are too wide may lead to unnecessary and incorrect out-of-specification (OOS) cases, resulting in bad reject decision for products. This study concentrates on analysis, through simulation, of the relation of method variability with specification limits for the total loaded dose of the active substance on the DES. The findings of this study point what levels of precision and accuracy are needed, in other words what is the magnitude of the allowable total error from all possible effects (both systematic and random) in an assay method in order to achieve the level of performance required for the methods applied routinely for the evaluation of the total loaded dose of DES as part of lot release/stability testing.