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Robert Combes

Publications and source records attributed to Robert Combes.

At least 19 recordsLinked to original sources
PubMed2006

TGN1412: time to change the paradigm for the testing of new pharmaceuticals.

Clinical studies in human volunteers are an essential part of drug development. These studies are designed to account for possible differences between the effects of pharmaceutical products in preclinical studies and in humans. However, the tragic outcome of the recent Phase 1 clinical trial on TGN1412 casts considerable doubt over the relevance of this traditional drug development paradigm to the testing of therapeutic agents for human use. The role of alternatives to animal testing is considered, and a series of recommendations are made, which could ensure that clinical trials are well informed and based on the most relevant scientific information.

Amino Acid Sequence↗
PubMed2006

An update on TGN1412.

In the last issue of ATLA, we assessed whether the existing methods for assessing the safety and efficacy of new candidate medicines was adequate for the testing of humanised therapeutic agents. We made specific reference to the failed TGN1412 first-in-man study that took place earlier this year. This paper was circulated to experts and those involved in the development or testing of TGN1412. More recently, the Focus on Alternatives group has made a submission to the Expert Working Group that is currently considering how such incidences can be avoided in the future. Here, we provide an update of the events relating to the TGN1412 clinical trial.

Animals↗
PubMed2006

The relevance of genetically altered mouse models of human disease.

The impetus to develop useful models of human disease and toxicity has resulted in a number of large-scale mouse mutagenesis programmes. This, in turn, has stimulated considerable concern regarding the scientific validity and welfare of genetically altered mice, and the large numbers of mice that are required by such programmes. In this paper, the scientific advantages and limitations of genetically altered mice as models of several human diseases are discussed. We conclude that, while the use of some such mouse models has contributed considerably to an understanding of human disease and toxicity, other genetically altered mouse models have limited scientific relevance, and fewer have positively contributed to the development of novel human medicines. Suggestions for improving this unsatisfactory situation are made.

Animal Testing Alternatives↗
PubMed2006

Integrated testing strategies for use in the EU REACH system.

Integrated testing strategies have been proposed to facilitate the process of chemicals risk assessment to fulfil the requirements of the proposed EU REACH system. Here, we present individual, decision-tree style, strategies for the eleven major toxicity endpoints of the REACH system, including human health effects and ecotoxicity. These strategies make maximum use of non-animal approaches to hazard identification, before resorting to traditional animal test methods. Each scheme: a) comprises a mixture of validated and non-validated assays (distinguished in the schemes); and b) decision points at key stages to allow the cessation of further testing, should it be possible to use the available information to classify and label and/or undertake risk assessment. The rationale and scientific justification for each of the schemes, with respect to the validation status of the tests involved and their individual advantages and limitations, will be discussed in detail in a series of future publications.

Animal Testing Alternatives↗
PubMed2006

The UK Food Standards Agency draft report on variability and uncertainty in toxicology: a response by FRAME.

At the request of the Food Standards Agency, the Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment (COT) established a Working Group on Variation and Uncertainty in Toxicology (WG VUT). In April 2006, the WG VUT produced a draft report for public consultation. FRAME made a submission in response to this consultation in July 2006. We commend the WG VUT for its comprehensive account of many of the problems associated with risk assessment, and for making recommendations about the problems that need to be addressed. We were particularly encouraged by the WG VUTs recognition of the need for guidelines on how toxicological studies should be conducted and data analysed. However, we believe that the report has not achieved all of its objectives. It does not adequately consider how modern technologies, experimental design, statistical analysis and species extrapolation can be used in practice to address variability and uncertainty. There is a disproportionate focus on the sources of variability and uncertainty in human data, with relatively little consideration of how variation and uncertainty due to animal tests can be addressed. Furthermore, it is clear that, until the advantages and limitations of all toxicological methods are fully appraised and testing strategies and guidelines are agreed, the scope for improving the existing approaches to risk assessment will be severely limited. Hence, the use of alternative methods for hazard identification and characterisation merit more consideration than they were given in the draft report.

Animals↗
PubMed2006

Introduction to the EU REACH legislation.

FRAME initiatives on the European Union REACH (Registration, Evaluation and Authorisation of Chemicals) system for the safety testing and risk assessment of chemicals, first proposed as a White Paper in 2001, are summarised. These initiatives considered the scientific and animal welfare issues raised by the REACH proposals, and resulted in a number of suggestions for improvement, many of which seem to have been adopted during the current progress of the legislation through the European Council and European Parliament.

Animal Testing Alternatives↗
PubMed2006

An overall strategy for the testing of chemicals for human hazard and risk assessment under the EU REACH system.

In its White Paper, Strategy for a Future Chemicals Policy, published in 2001, the European Commission (EC) proposed the REACH (Registration, Evaluation and Authorisation of CHemicals) system to deal with both existing and new chemical substances. This system is based on a top-down approach to toxicity testing, in which the degree of toxicity information required is dictated primarily by production volume (tonnage). If testing is to be based on traditional methods, very large numbers of laboratory animals could be needed in response to the REACH system, causing ethical, scientific and logistical problems that would be incompatible with the time-schedule envisaged for testing. The EC has emphasised the need to minimise animal use, but has failed to produce a comprehensive strategy for doing so. The present document provides an overall scheme for predictive toxicity testing, whereby the non-animal methods identified and discussed in a recent and comprehensive ECVAM document, could be used in a tiered approach to provide a rapid and scientifically justified basis for the risk assessment of chemicals for their toxic effects in humans. The scheme starts with a preliminary risk assessment process (involving available information on hazard and exposure), followed by testing, based on physicochemical properties and (Q)SAR approaches. (Q)SAR analyses are used in conjunction with expert system and biokinetic modelling, and information on metabolism and identification of the principal metabolites in humans. The resulting information is then combined with production levels and patterns of use to assess potential human exposure. The nature and extent of any further testing should be based strictly on the need to fill essential information gaps in order to generate adequate risk assessments, and should rely on non-animal methods, as far as possible. The scheme also includes a feedback loop, so that new information is used to improve the predictivity of computational expert systems. Several recommendations are made, the most important of which is that the European Union (EU) should actively promote the improvement and validation of (Q)SAR models and expert systems, and computer-based methods for biokinetic modelling, since these offer the most realistic and most economical solution to the need to test large numbers of chemicals.

Journal Article↗
PubMed2006

A critical assessment of the European Commission's proposals for the risk assessment and registration of chemical substances in the European Union.

In May, 2003, the European Commission published detailed proposals relating to its 2001 White Paper--Strategy for a Future Chemicals Policy. The White Paper described a new registration system called the REACH (Registration, Evaluation and Authorisation of Chemicals) system, for both new and existing chemicals. Subsequently, these detailed proposals were available for an eight-week consultation period for stakeholders to voice their views and concerns. In this paper, we describe our reactions to the Commissions more-detailed proposals. These include the creation of a European Chemicals Agency to implement the REACH system in conjunction with Competent Authorities (CAs) in Member States and the Commission itself. Unfortunately, many of our concerns and suggestions, previously voiced and shared with several other key stakeholders, remain unanswered, but are as relevant as when the White Paper was published. In particular, we are concerned about the lack of a clear and coherent strategy. There is no guidance for registrants on intelligent testing to maximise the use of non-animal approaches to safety testing, based on a combination of factors for estimating exposure levels, rather than mainly on production volumes. We are also concerned about the absence of a clear programme for the development, improvement and validation of new alternative methods, in conjunction with the Commissions own unit, the European Centre for the Validation of Alternative Methods, as well as other organisations with relevant expertise and experience, including FRAME. Finally, we explain why such measures should be introduced, together with clearer guidelines for the respective roles of the Agency, the CAs and the Commission in implementing and harmonising the REACH system at the European Union and Member State levels. A series of recommendations are made, to improve the situation and to improve the risk assessment process.

Journal Article↗
PubMed2006

A survey of stakeholder organisations on the proposed new European chemical policy.

In February 2001, the European Commission published a White Paper proposing that a single new system of chemical regulation should be applied throughout the Member States of the European Union. The proposed Registration, Evaluation and Authorisation of Chemicals (REACH) system was to include both new and existing chemicals, with the aim of ensuring that sufficient pertinent data were made available to enable human health and the environment to be protected. The policy was founded on the principle of sustainable industrial development, and ambitiously attempted to incorporate the needs and views of key stakeholder organisations, such as industry, trade associations, consumer groups, environmentalists, animal welfarists and Member State governments. During the period between the publication of the White Paper and the on-line publication of consultation documents, as part of a public consultation exercise, in May 2003, many of these key stakeholder organisations produced material in support of or critical of the White Paper, either in part or as a whole. In this paper, we have attempted to review this extensive material and to present it in the context of the current chemical regulatory system that the REACH system will replace. Emphasis is placed on the impact of the new policy on the number of animals used in the testing regimes within the REACH system and the inclusion of alternative methods into the legislation. Although supportive of the overriding aims of the new policy, FRAME believes that the fundamental concept of a risk-free environment is flawed, and that the new REACH system will involve the unjustifiable use of millions of laboratory animals. The new policy does include alternative methods, particularly for base set substances. Nevertheless, alternative testing methods that are already available have been excluded and replaced with outdated in vivo versions. There is also insufficient detail with regard to the further development and validation of alternative methods, particularly for substances of high concern, such as endocrine disrupters or reproductive toxins, for which no alternative testing methods currently exist.

Journal Article↗
PubMed2006

FRAME and the Royal Commission on Environmental Pollution: common recommendations for assessing risks posed by chemicals under the EU REACH system.

This document discusses recommendations made by FRAME and the Royal Commission on Environmental Pollution (RCEP) with regard to the current European Commission proposals on the Registration, Evaluation and Authorisation of Chemicals (REACH) system for assessing the risks of chemicals to humans, wildlife and the environment. Of several common aims and recommendations, the two most important are: a) the greater use of non-animal testing methods, especially computational prediction methods (for example, [quantitative] structure-activity relationships, expert systems and biokinetic modelling) for prioritising chemicals for hazard assessment; and b) the greater use of intelligent exposure-based targeted risk assessment, with less emphasis being placed on tonnage-triggers. FRAME has produced a decision-tree testing scheme to illustrate the way in which these approaches could be used, together with in vitro test methods. This scheme has been slightly modified to take account of proposals subsequently made by the RCEP. In addition, FRAME points out that new and improved computational methods are needed through more coordinated research, and that these and existing methods need to be validated. The similarities between the independent publications of FRAME and the RCEP add weight to the recommendations that each have made concerning the implementation of the REACH system.

Journal Article↗
PubMed2006

A scientific and animal welfare assessment of the OECD Health Effects Test Guidelines for the safety testing of chemicals under the European Union REACH system.

We have assessed each of the OECD Health Effects Test Guidelines (TGs) that were included in an annex to the Internet consultation issued by the European Commission relating to the Registration, Evaluation and Authorisation of Chemicals (REACH) legislation for the testing of new and existing chemical substances. Each guideline has been analysed with respect to its design and its scientific and animal welfare implications, the extent to which it makes use of modern techniques, and its suitability to be used in the REACH system for the testing of large numbers of chemicals. The scientific basis of the test and its justification are considered, as well as the numbers of animals required, and the potential adverse effects on them. The prospects and possibilities for applying the Three Rs (reduction, refinement and replacement) to each of the TGs are also discussed. We have proposed an overall testing strategy for how these TGs and other methods could best be deployed for chemicals testing, should it be necessary to fill data gaps. Certain TGs have been omitted from the strategy, when we have considered them to be unnecessary for chemicals testing. A series of recommendations has been made for improving the TGs with regard to both their scientific content and ways in which they could be better designed in relation to optimising the use of the animals concerned, and minimising adverse welfare consequences to them. Our investigations show that there is an urgent need to update the TGs to reflect modern techniques and methods, and to use current approaches for applying refinement strategies to improve the scientific and animal welfare aspects of the procedures used. Improvements can and should be made in all aspects of toxicity testing, from sample preparation, and animal housing, care and feeding, to dose formulation, test material administration, and the histopathological and clinical analysis of tissue samples. Opportunities for streamlining individual assays are very limited, but testing could be made more efficient by: a) only undertaking studies that provide relevant data; b) making greater use of screens and preliminary testing; c) applying some tests simultaneously to the same animals; d) using one sex; and e) eliminating redundant tests. In conclusion, it is clear that, as they stand, the OECD Health Effects TGs are unsuitable for use in the European Union REACH system, for which potentially very large numbers of laboratory animals will be needed for the testing of a very large number of chemicals.

Journal Article↗
PubMed2006

A review of the status of alternative approaches to animal testing and the development of integrated testing strategies for assessing the toxicity of chemicals under REACH--a summary of a DEFRA-funded project conducted by Liverpool John Moores University and FRAME.

Liverpool John Moores University and FRAME were recently awarded a DEFRA tender to conduct a review of the status of alternative approaches to animal testing, and to recommend further research with regard to the forthcoming European Union REACH (Registration, Evaluation and Authorisation of Chemicals) system for the safety testing and risk assessment of chemicals. The outcome of the project is summarised, including the prospects for in vitro and in silico testing, areas where reduction and refinement could be applied, and how decision-tree integrated testing strategies could be used to reduce the number of animals needed to fulfil the testing requirements of the REACH system. This paper is a prelude to a series of individual papers on detailed suggestions for applying non-animal methods to each of the major toxicity endpoints in REACH.

Animal Testing Alternatives↗
PubMed2005

ESTIV questionnaire on the acquisition and use of primary human cells and tissue in toxicology.

The ability to use human cells and tissues in toxicology research and testing has the benefit that it obviates the need to undertake species extrapolation when assessing human hazard. However, obtaining and using human cells and tissues is logistically difficult, ethically complex and is a potential source of infections to those coming into contact with human cell material. The issue is also controversial, with the recent EU legislation draft on tissue engineering, and also due to some instances of human material being obtained and used without informed consent. There are also varying regulations and attitudes relating to the use of human cells and tissues throughout Member States of the EU, and there is a need for harmonisation. The European Society of Toxicology in Vitro (ESTIV) Executive Board and the European Network of Human Research Tissue Banks (ENRTB) have conducted a survey to ascertain the extent to which human cells and tissues are used by its members, how these are obtained, what local regulations are in force, how the material is used, and the advantages and disadvantages experienced by members in using such material, as opposed to cell lines. The results obtained have been compared with the results from a previous survey conducted in 2000. It is hoped that this information will help to facilitate the process of acquiring and using human cells and tissues in a safe and effective way to promote the use of non-animal approaches for investigating the mechanisms of toxicity, and for predicting the toxic hazard of substances.

Animal Testing Alternatives↗
PubMed2005

Toxicity testing: creating a revolution based on new technologies.

Biotechnology is evolving at a tremendous rate. Although drug discovery is now heavily focused on high throughput and miniaturized screening, the application of these advances to the toxicological assessment of chemicals and chemical products has been slow. Nevertheless, the impending surge in demands for the regulatory toxicity testing of chemicals provides the impetus for the incorporation of novel methodologies into hazard identification and risk assessment. Here, we review the current and likely future value of these new technologies in relation to toxicological evaluation and the protection of human health.

Animal Testing Alternatives↗