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Purpose
This article describes preclinical development of cell-based medicinal products for European markets and discusses European regulatory mechanisms open to developers to aid successful product development. Cell-based medicinal products are diverse, including cells that are autologous or allogeneic, have been genetically modified, or not, or expanded ex vivo, and applied systemically or to an anatomical site different to that of their origin; comments applicable to one product may not be applicable to others, so bespoke development is needed, for all elements - quality, preclinical and clinical.Methods
After establishing how the product is produced, proof of potential for therapeutic efficacy, and then safety, of the product need to be determined. This includes understanding biodistribution, persistence and toxicity, including potential for malignant transformation. These elements need to be considered in the context of the intended clinical development.Results
This article describes regulatory mechanisms available to developers to support product development that aim to resolve scientific issues prior to marketing authorization application, to enable patients to have faster access to the product than would otherwise be the case.Conclusions
Developers are encouraged to be aware of both the scientific issues and regulatory mechanisms to ensure patients can be supplied with these products.93.
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Graham F. Whale James Dawick Christopher B. Hughes Delina Lyon Peter J. Boogaard 《Critical reviews in toxicology》2018,48(4):273-296
Gas-to-liquid (GTL) products are synthetic hydrocarbons produced from natural gas using a catalytic process known as the Fischer–Tropsch process. This process yields a synthetic crude oil that consists of saturated hydrocarbons which can subsequently be refined to a range of products analogous to those obtained from petroleum refining. However, in contrast to their petroleum-derived analogs, GTL products are essentially free of unsaturated or aromatic compounds and do not contain any sulfur-, oxygen-, or nitrogen-containing compounds. Under new chemical substance notification requirements, an extensive testing program covering the entire portfolio of GTL products has been undertaken to assess their hazardous properties to human health and environment. The results of these studies have been summarized in a two-part review. Part 1 provides an overview of the mammalian toxicity hazardous properties of the various GTL products. This second part of the review focuses on the aquatic, sediment, terrestrial, and avian toxicity studies which assess the ecotoxicological hazard profile of the GTL products. Many challenges were encountered during these tests relating to dosing, analysis and interpretation of results. These are discussed with the intent to share experiences to help inform and shape future regulatory mandates for testing of poorly soluble complex substances. As was the case with the mammalian toxicology review, there were a few cases where adverse effects were found, but overall the GTL products were found to exert minimal adverse ecotoxicological effects and these were less severe than effects observed with their conventional, petroleum-derived analogs. 相似文献
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Background: Excessive drinking is commonplace at UK Universities. Individuals may misperceive how much they drink compared to others and are less likely to think that they will suffer adverse consequences. Young people often distance themselves and their friends from ‘problem drinkers’. Objectives: The aim of the study was to explore how student drinkers compared their own drinking behaviors to the drinking behaviors of others. Methods: An online survey was completed by 416 students aged 18–30 (68.5% female). They were asked ‘how do you think your drinking compares with other people like you?' and ‘how do you think your behavior when you drink compares with other people like you?’ Answers were subjected to thematic analysis. Results: The first main theme was about ‘identification as a ‘good’ drinker’. Participants suggested their own behavior when drinking was similar to their sober behavior. Further, they viewed themselves as more able to maintain a balance between staying in control and having fun while drinking. The second main theme was about ‘distancing from being a ‘bad’ drinker. Participants distanced themselves from negative prototypical drinkers, such compulsive or anti-social drinkers. They also attributed their own drinking behaviors to situational factors, but described other people as intentionally violent or aggressive. Conclusions/Importance: These findings may explain the failure of some health messages to change drinking behaviors. If drinkers perceive that their behavior when they drink is better than other people's then they may discount intervention messages. Targeting these biases could be incorporated into future interventions. 相似文献
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Emily E. Burns Laura J. Carter Jason Snape Jane Thomas-Oates 《Journal of toxicology and environmental health. Part B, Critical reviews》2018,21(3):115-141
Pharmaceuticals are ubiquitous in the natural environment with concentrations expected to rise as human population increases. Environmental risk assessments are available for a small portion of pharmaceuticals in use, raising concerns over the potential risks posed by other drugs that have little or no data. With >1900 active pharmaceutical ingredients in use, it would be a major task to test all of the compounds with little or no data. Desk-based prioritization studies provide a potential solution by identifying those substances that are likely to pose the greatest risk to the environment and which, therefore, need to be considered a priority for further study. The aim of this review was to (1) provide an overview of different prioritization exercises performed for pharmaceuticals in the environment and the results obtained; and (2) propose a new holistic risk-based prioritization framework for drugs in the environment. The suggested models to underpin this framework are discussed in terms of validity and applicability. The availability of data required to run the models was assessed and data gaps identified. The implementation of this framework may harmonize pharmaceutical prioritization efforts and ensure that, in the future, experimental resources are focused on molecules, endpoints, and environmental compartments that are biologically relevant. 相似文献
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