Ethics of Research involving animals
Animal use by the pharmaceutical industry (Chapter 8)
10.19 Use of animals within the pharmaceutical industry is a crucial part of the research and development process for new medicines. The number of animals used by the pharmaceutical industry has fallen over the last two decades due to the application of new technologies, new materials and increased use of computational analysis (see paragraph 8.4). In the UK in 2003, 36 percent of the total number of procedures performed on animals were undertaken by the commercial sector.
10.20 Relatively small numbers of animals are used in the early stages of drug discovery, particularly in the identification of targets for possible medicines. Many of the animals used at this stage are GM mice. They are used to ascertain whether, for example, specific receptors might respond to chemical compounds which can be developed into new medicines. Animal models that reproduce relevant aspects of human genetic conditions, such as sickle cell anaemia, can be used to test how people affected by the disorder may react to different chemical compounds (see paragraph 8.16).
10.21 Sixty to eighty percent of animals used by the pharmaceutical industry are involved in the process of characterising promising candidate medicines (Table 8.1). Rodents are most commonly used, but larger animals, including rabbits, dogs and primates, are also used (see paragraph 10.24). Before a potential medicine is tested in human trials, the regulatory authorities must ensure that it has an acceptable balance of safety and efficacy, usually requiring data obtained from animal tests. Twenty five percent of the total number of procedures using animals in 2002 in the UK were conducted for the purpose of ‘applied human medicine’. Once a medicine is in clinical trials, animal tests continue to be carried out (paragraphs 8.27 and 8.29).
10.22 For certain biological compounds such as vaccines, animal testing is required for each batch that is produced, to ensure potency and safety (see paragraphs 8.35-8.36). Depending on the type of test there can be serious welfare implications. For example, if death is the required endpoint, or if it is the easiest endpoint to observe reliably, it may be used. In specific cases, the terminal stages of a lethal endpoint may not involve much, if any, suffering as the animal may be comatose. However, the suffering that may have taken place beforehand can be substantial and may involve considerable distress including loss of appetite, malaise, convulsions or imbalance rather than pain.