Scientific and Regulatory Procedures: Use of Dogs

Alex Mayer Excerpts

Monday 28th April 2025 Westminster Hall

[Irene Campbell]

I fully agree, and I will speak a little about that later.

Modern, non-animal methods give the best possible chance of securing medical progress, since they are not hampered by translating from one species to another. An estimated 92% of drugs fail in human clinical trials, even though they had passed pre-clinical tests, including animal tests. Just over 30% of those that pass are subsequently re-labelled with warnings of side effects not predicted by animal tests, and almost 10% are completely withdrawn from the market.

New non-animal methods, based directly on human biology, include the use of computer modelling and organ-on-a-chip technology, which can be much more relevant to the human body. I went on lab trip recently with the APPG on phasing out animal experiments in medical research to visit the Animal Replacement Centre of Excellence at Queen Mary University of London, and I saw in person the pioneering work that is being done to provide medical breakthroughs without the use of animals.

[Alex Mayer (Dunstable and Leighton Buzzard) (Lab)]

Does my hon. Friend agree that there is a bit of a disconnect between the scientific possibility of non-animal alternatives and what is happening on the ground? For decades, there have been suggestions of ways that we can use non-animal alternatives, yet we are not using them. Will she also commend the work of Cruelty Free International, which is producing a new list that explains exactly how we could switch from one type of experiment to the other?

[Irene Campbell]

I fully agree with everything that my hon. Friend said, and I will speak about that in a minute.

A study published in Communications Medicine found that the non-animal liver-on-a-chip device was able to correctly identify 87% of drugs that carried a risk of liver toxicity in humans, despite having passed through animal safety tests. Another example is research at Edge Hill University, where scientists are developing a human cell model of the blood-brain barrier to study the link between irregular heartbeat and an increased risk of brain damage, stroke and dementia. Normally, large animals such as dogs would be used to study heart disease. This work will be relevant to patients and will provide a real case for phasing out testing on dogs.

Comprehensive analysis in a paper authored by Dr Jarrod Bailey found that dogs are highly inconsistent predictors of toxic responses in humans and that, when considering whether a compound should proceed to testing on humans, the predictions that dogs can provide are little better than those that could be obtained by chance or tossing a coin. A simple example is that some foods, such as grapes and chocolate, are poisonous to dogs, and some drugs that are safe for humans, such as ibuprofen, are highly toxic to dogs, even in small doses.

Animals are used in research because of their genetic similarity to humans, yet although we share up to 98% of our DNA with some animals, the small yet important differences make us distinct. There are many historical examples of deadly drugs that appeared safe in animal tests: thalidomide was tested safely on animals, but caused severe birth defects in thousands of babies, and the painkiller Vioxx was linked to thousands of heart attacks and deaths, despite cardio-protective results obtained in animal tests, including on dogs.

The current approach to alternatives to animal testing is to fund the development and dissemination of techniques that replace, reduce and refine the use of animals in research—more commonly known as the three Rs. However—in relation to the point made earlier—there is little funding for non-animal methods. The all-party parliamentary group on human-relevant science estimated that human-relevant, non-animal method funding

“represents between 0.2% and 0.6% of total biomedical research funding in the UK and ~0.02% of the total public expenditure…on R&D.”