References of "Dewé, Walthère"
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See detailMethodologies for the transfer of analytical methods: A review.
Rozet, Eric ULg; Dewé, Walthère ULg; Ziemons, Eric ULg et al

in Journal of Chromatography. B : Analytical Technologies in the Biomedical & Life Sciences (2009), 877

The transfer of a method from a laboratory to a production site is an important step in the development cycle of new pharmaceutical products. Method transfers are increasingly implemented due to the ... [more ▼]

The transfer of a method from a laboratory to a production site is an important step in the development cycle of new pharmaceutical products. Method transfers are increasingly implemented due to the economical pressure coming from the rationalization of production sites, analytical subcontracting and fusion of pharmaceutical groups. However, no official guidance regarding study design, data analysis, or decision procedures is present neither in FDA documents nor in ICH documents for method transfers. The experiments performed in such a transfer and the methodology used to accept or reject it should be fitted for purpose. In order to provide to analysts a global view of the problematic of analytical method transfer, this paper reviews the documentation available in the scientific literature about the design of transfer studies and the required sample size. Special focus is also made on the statistical methodologies available for decision making with particular emphasis on risk management. Examples of transfer of pharmaceutical, bio-pharmaceutical and biological methods published in the literature are reviewed in order to illustrate the various possibilities among the strategies for methods transfer. [less ▲]

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See detailHarmonization of strategies for the validation of quantitative analytical procedures: a SFSTP proposal part IV. Examples of application.
Hubert, Philippe ULg; Nguyen-Huu, J.-J.; Boulanger, Bruno ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2008), 48(3), 760-71

A harmonized approach for the validation of analytical methods based on accuracy profile was introduced by a SFSTP commission on the validation of analytical procedure. This fourth and last document aims ... [more ▼]

A harmonized approach for the validation of analytical methods based on accuracy profile was introduced by a SFSTP commission on the validation of analytical procedure. This fourth and last document aims at illustrating this methodology and the statistics used. Therefore the validation of real case methods are proposed such as methods for the quality control of drugs, for the quantitation of impurities in drug substances, for bioanalysis or for the determination of nutriments. Furthermore, different types of analytical methods are used in order to demonstrate the applicability of the proposed approach to a wide range of methods such as liquid chromatography (LC-UV, LC-MS), spectrophotometry or ELISA. [less ▲]

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See detailRisk-Based Approach for the Transfer of Quantitative Methods: Bioanalytical Applications
Rozet, Eric ULg; Dewé, Walthère ULg; Morello, R. et al

in Journal of Chromatography. A (2008), 1189

The transfer of analytical methods from a sending laboratory to a receiving one requires to guarantee that this last laboratory will obtain accurate results. Undeniably method transfer is the ultimate ... [more ▼]

The transfer of analytical methods from a sending laboratory to a receiving one requires to guarantee that this last laboratory will obtain accurate results. Undeniably method transfer is the ultimate step before routine implementation of the method at the receiving site. The conventional statistical approaches generally used in this domain which analyze separately the trueness and precision characteristics of the receiver do not achieve this. Therefore, this paper aims first at demonstrating the applicability of two recent statistical approaches using total error-based criterion and taking into account the uncertainty of the true value estimate of the sending laboratory, to the transfer of bioanalytical methods. To achieve this, they were successfully applied to the transfer of two fully automated liquid chromatographic method coupled on-line to solid-phase extraction. The first one was dedicated to the determination of three catecholamines in human urine using electrochemical detection, and the second one to the quantitation of N-methyl-laudanosine in plasma using fluorescence detection. Secondly, a risk-based evaluation is made in order to understand why classical statistical approaches are not sufficient to provide the guarantees that the analytical method will give most of the time accurate results during its routine use. Finally, some recommendations for the transfer studies are proposed. [less ▲]

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See detailHarmonization of strategies for the validation of quantitative analytical procedures - A SFSTP proposal - Part II
Hubert, Philippe ULg; Nguyen-Huu, J.-J.; Boulanger, Bruno ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2007), 45(1), 70-81

As reported in a previous paper[1], the main objective of the new commission of the Societe Francaise des Sciences et Techniques Pharmaceutiques (SFSTP) was the harmonisation of approaches for the ... [more ▼]

As reported in a previous paper[1], the main objective of the new commission of the Societe Francaise des Sciences et Techniques Pharmaceutiques (SFSTP) was the harmonisation of approaches for the validation of quantitative analytical procedures. In a series of meetings, members of this Commission have first tried to review the objectives of analytical methods and the objectives of validation methods and to recommend the use of two-sided beta-expectation tolerance intervals for total error of validation samples (accuracy profile) in the acceptance/rejection of analytical method in validation phase. In the context of the harmonization, the other objectives were: (i) to propose a consensus on the norms usually recognized, while widely incorporating the ISO terminology; (ii) to recommend to validate the analytical procedure accordingly to the way it will be used in routine; (iii) to elaborate a rational, practical and statistically reliable strategy to assure the quality of the analytical results generated. This strategy has been formalised in a guide and the three latter objectives made by the Commission are summarised in the present paper which is the second part of summary report of the SFSTP commission. The SFSTP guide has been produced to help analysts to validate their analytical methods. It is the result of a consensus between professionals having expertise in analytical and/or statistical fields. The suggestions presented in this paper should therefore help the analyst to design and perform the minimum number validation experiments needed to obtain all the required information to establish and demonstrate the reliability of its analytical procedure. (C) 2007 Elsevier B.V. All rights reserved. [less ▲]

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See detailUsing tolerance intervals in pre-study validation of analytical methods to predict in-study results - The fit-for-future-purpose concept
Rozet, Eric ULg; Hubert, Cédric ULg; Ceccato, Attilio ULg et al

in Journal of Chromatography. A (2007), 1158(1-2), 126-137

It is recognized that the purpose of validation of analytical methods is to demonstrate that the method is suited for its intended purpose. Validation is not only required by regulatory authorities, but ... [more ▼]

It is recognized that the purpose of validation of analytical methods is to demonstrate that the method is suited for its intended purpose. Validation is not only required by regulatory authorities, but is also a decisive phase before the routine use of the method. For a quantitative analytical method the objective is to quantify the target analytes with a known and suitable accuracy. For that purpose, first, a decision about the validity of the method based on prediction is proposed: a method is declared proper for routine application if it is considered that most of the future results generated will be accurate enough. This can be achieved by using the "beta-expectation tolerance interval" (accuracy profile) as the decision tool to assess the validity of the analytical method. Moreover, the concept of "fit-for-purpose" is also proposed here to select the most relevant response function as calibration curve, i.e. choosing a response function based solely on the predicted results this model will allow to obtain. This paper reports four case studies where the results obtained with quality control samples in routine were compared to predictions made in the validation phase. Predictions made using the "beta-expectation tolerance interval" are shown to be accurate and trustful for decision making. It is therefore suggested that an adequate way to conciliate both the objectives of the analytical method in routine analysis and those of the validation step consists in taking the decision about the validity of the analytical method based on prediction of the future results using the most appropriate response function curve, i.e. the fit-for-future-purpose concept. [less ▲]

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See detailImprovement of the decision efficiency of the accuracy profile by means of a desirability function for analytical methods validation - Application to a diacetyl-monoxime colorimetric assay used for the determination of urea in transdermal iontophoretic extracts
Rozet, Eric ULg; Wascotte, Valentine; Lecouturier, Nathalie et al

in Analytica Chimica Acta (2007), 591(2), 239-247

Validation of analytical methods is a widely used and regulated step for each analytical method. However, the classical approaches to demonstrate the ability to quantify of a method do not necessarily ... [more ▼]

Validation of analytical methods is a widely used and regulated step for each analytical method. However, the classical approaches to demonstrate the ability to quantify of a method do not necessarily fulfill this objective. For this reason an innovative methodology was recently introduced by using the tolerance interval and accuracy profile, which guarantee that a pre-defined proportion of future measurements obtained with the method will be included within the acceptance limits. Accuracy profile is an effective decision tool to assess the validity of analytical methods. The methodology to build such a profile is detailed here. However, as for any visual tool it has a part of subjectivity. It was then necessary to make the decision process objective in order to quantify the degree of adequacy of an accuracy profile and to allow a thorough comparison between such profiles. To achieve this, we developed a global desirability index based on the three most important validation criteria: the trueness, the precision and the range. The global index allows the classification of the different accuracy profiles obtained according to their respective response functions. A diacetyl-monoxime colorimetric assay for the determination of urea in transdermal iontophoretic extracts was used to illustrate these improvements. [less ▲]

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See detailUsing total error as decision criterion in analytical method transfer
Dewé, Walthère ULg; Govaerts, Bernadette; Boulanger, Bruno ULg et al

in Chemometrics and Intelligent Laboratory Systems (2007), 85(2), 262-268

An analytical transfer is a complete process that consists in transferring a validated analytical method from a sending laboratory (called sender) to a receiving laboratory (called receiver) after having ... [more ▼]

An analytical transfer is a complete process that consists in transferring a validated analytical method from a sending laboratory (called sender) to a receiving laboratory (called receiver) after having experimentally demonstrated that it also masters the method. The decision to transfer an analytical method is usually taken based on the combination of two criteria: one about systematic error and one about random errors. These usual criteria, their combination and their limitations are described in this paper. As it is for method validation, total error-based approaches should be also considered in method transfer. Two approaches are proposed in order to have a total error-based criterion and to take into account the precision of the true value estimate. In the first approach, a beta-expectation tolerance interval similar to the one used in method validation is calculated and then compared to acceptance limits around the estimate of the true value. The second approach, found as slightly more powerful than the first one, consists in estimating the probability to have a result outside these acceptance limits. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailHarmonization of strategies for the validation of quantitative analytical procedures - A SFSTP proposal - Part III
Hubert, Philippe ULg; Nguyen-Huu, J. J.; Boulanger, Bruno ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2007), 45(1), 82-96

In the first two documents [Ph. Hubert, J.J. Nguyen-Huu, B. Boulanger, E. Chapuzet, P. Chiap, N. Cohen, P.A. Compagnon, W. Dewe, M. Feinberg. M. Lallier, M. Laurentie, N. Mercier, G. Muzard, C. Nivet, L ... [more ▼]

In the first two documents [Ph. Hubert, J.J. Nguyen-Huu, B. Boulanger, E. Chapuzet, P. Chiap, N. Cohen, P.A. Compagnon, W. Dewe, M. Feinberg. M. Lallier, M. Laurentie, N. Mercier, G. Muzard, C. Nivet, L. Valat, J. Pharm. Biomed. Anal. 36 (2004) 579-586; Ph. Hubert, J.J. Nguyen-Huu. B. Boulanger, E. Chapuzet, P. Chiap, N. Cohen, P.A. Compagnon, W. Dewe, M. Feinberg, M. Lallier, M. Laurentie, N. Mercier, G. Muzard. C. Nivet, L. Valat, E. Rozet, J. Pharm. Biomed. Anal., in press], a recent SFSTP Commission on the validation of analytical procedure has introduced a harmonized approach for the validation of analytical procedures. In order to complete this guide, the statistical methodology allowing to correctly conclude about the validity of a procedure is proposed in this third part of the guide. Indeed all the steps to obtain the decision tool namely the accuracy profile are described and illustrated step by step by a numerical example. This tool, based on the concept of total error (bias + standard deviation) build with a P-expectation tolerance interval, allows to easily take the right decision and simultaneously minimizing the risk of the future use of the analytical procedure. (C) 2007 Elsevier B.V. All rights reserved. [less ▲]

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See detailGuide for validation of analytical procedures
Oprean, R.; Rozet, Eric ULg; Dewé, Walthère ULg et al

Book published by Medicala Universitara “Iuliu Hatieganu” (2007)

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See detailThe transfer of a LC-UV method for the determination of fenofibrate and fenofibric acid in Lidoses: Use of total error as decision criterion
Rozet, Eric ULg; Mertens, Bénédicte; Dewé, Walthère ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2006), 42(1), 64-70

Two new statistical approaches to assess the validity of the transfer of a LC-UV method for the determination of fenofibrate and fenofibric acid were investigated and compared to the conventional ... [more ▼]

Two new statistical approaches to assess the validity of the transfer of a LC-UV method for the determination of fenofibrate and fenofibric acid were investigated and compared to the conventional approaches generally used in this domain. These new approaches, namely the Tolerance Interval and the Risk approaches, are based on the simultaneous evaluation of the systematic (or trueness) and random (or precision) errors of the transfer into a single criterion called total error (or accuracy). The results of the transfer showed that only the total error based approaches fulfilled the objective of an analytical method transfer, i.e. to give guarantees that each future measurement made by the receiving laboratory will be close enough to the true value of the analyte in the sample. Furthermore the Risk approach was the most powerful one and allowed the estimation of the risk to have future measurements out of specification in the receiving laboratory, therefore being a risk management tool. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailComparison of FT-NIR transmission and UV-vis spectrophotometry to follow the mixing kinetics and to assay low-dose tablets containing riboflavin
Bodson, Cédric; Dewé, Walthère ULg; Hubert, Philippe ULg et al

in Journal of Pharmaceutical & Biomedical Analysis (2006), 41(3), 783-790

For several years, near-infrared spectroscopy (NIRS) has become an analytical technique of great interest for the pharmaceutical industry, particularly for the non-destructive analysis of dosage forms ... [more ▼]

For several years, near-infrared spectroscopy (NIRS) has become an analytical technique of great interest for the pharmaceutical industry, particularly for the non-destructive analysis of dosage forms. The goal of this study is to show the capacity of this new technique to assay the active ingredient in low-dosage tablets. NIR spectroscopy is a rapid, non-destructive technique and does not need any sample preparation. As an example, a binary mixture of microcrystalline cellulose and riboflavin was used to prepare tablets of different weights by direct compression. A prediction model was built by using a partial least square regression fit method. The NIR assay was performed by transmission. The results obtained by NIR spectroscopy were compared with a conventional UV-vis spectrophotometry method. The study showed that tablets can be individually analysed by NIR with high accuracy. It was shown that the variability of this new technique is less important than that of the conventional method which is the UV-vis spectrophotometry. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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