This question has been asked persistently for decades. 

Patients who benefit from medicines for relief from conditions such as cystic fibrosis, heart disease, tuberculosis and more recently COVID-19, have in vivo testing to thank for safe, effective and timely interventions. In fact, to many people inside and outside the scientific world, modern medicine as we know it wouldn’t be where it is today without research that involves the use of animals in drug discovery, preclinical laboratory testing and clinical trials.

As a long-established provider of regulatory toxicology testing, we are very familiar with the drug development lifecycle and the race to get to market, from initial screening of drug candidates, through preclinical research, and on to batch release of the finished product. 

In 2022 alone there were 37 novel drugs approved by the FDA for the US market. Each of these will have required the gathering and analysis of data from animal models as part of the regulatory approval process. 

With a 90% failure rate of drug candidates to get to market (and only 10% of those failures attributable to lack of commercial interest or poor strategic planning), the approval rate reveals that over 300 potential treatments failed to reach the required regulatory threshold for safe use in humans, with between 40% and 50% of these due to a lack of clinical efficacy (i.e. the drug wasn’t able to produce its intended effect in humans).

Of most concern though is that around 30% of failures are due to unmanageable toxicity or side effects, with a further 10%-15% due to unacceptable pharmacokinetic properties (i.e. how well a drug is absorbed by and excreted from the body). By extrapolation this implies nearly half of drug candidate failures are because of potentially serious dangers posed to humans. Even more reason why patients who benefit from safe, effective, and timely interventions have in vivo testing to thank.

Why do we need animal testing?
Put simply, while animal testing has in the past fuelled the progression of medical research, we still need it today in order to protect humans from potentially harmful treatments.

Novel drugs, vaccines and medication can still only be deemed safe for humans and the environment after testing in a living organism, and nowhere has this been more apparent than in the COVID-19 pandemic. 

Extensive in vivo testing evidenced the safety and efficacy of mRNA vaccines throughout the SARS-COV-2 vaccine development process. In addition to reducing COVID-19 mortality, this work also validated the use of a new platform technology in a real-world public health scenario and enabled scientists to develop new ways to combat viral diseases of a similar nature. Although 6 million deaths have been reported to date, this number would have been significantly larger without the fast-track development of life-saving vaccines and their rapid deployment.

In vivo testing not only benefits vaccine research. It plays a key role in human diagnostics and therapeutics and has also propelled the development of veterinary medicine and treatments for diseases such as rabies and canine parvovirus. 

To answer the question then, animal testing is a vital cog in the wheel of safe drug development. It is essential to drug discovery, pharmaceutical development and ongoing progress in medical research and knowledge. 

Until robust alternative replacement methods of ensuring human safety enter the arena and are accepted by regulators, we will continue our commitment to working in a manner that abides by the three Rs. 

The three Rs of animal research
In the 1960’s, a concept known as the three Rs was introduced by two biologists, Russel and Burch. These principles have provided a framework for the bioresearch community to move towards alternative approaches to animal testing where possible. To summarise the three Rs: 

Wherever possible, we should replace the use of animals through alternative methods, including computer simulations, cell cultures, human clinical trials or other suitable routes.
 

We shouild reduce the quantity of animals required through the use of statistical methods, sharing of relevant data and optimising experiment design. 
 

When the use of animals is unavoidable, we should refine the testing environment, including better housing, minimised pain and stress and other appropriate methods to improve animal welfare.

Although there have been substantial inroads made towards replacing animal testing, we are yet to eliminate it entirely. This is because there are still circumstances in which animal testing is the only suitable option for pre-clinical testing. However, the laws that govern animal testing are strict and reassuring. 

Obtaining regulatory permission to use animals in a pre-clinical trial is a complex process, designed specifically to protect animal welfare. All testing is regulated in the UK under the Animals (Scientific Procedures) Act 1986. 

This law requires that any research project involving an animal – and that includes the work we do at Hoeford on behalf of our clients - must first be justified to the UK Home Office. This justification includes limiting the number of animals involved, welfare risk mitigation measures, and conclusive scientific evidence that no alternative non-animal tests are available. Only then will a license be issued to allow the work to commence.

Our commitment to the three Rs of animal testing
We have embedded the three Rs principles into the core of our testing services, and at Hoeford Research, we are committed to a fourth R – responsibility. 

We have a responsibility to our laboratory animals, society and the environment that drives the commitment of our scientific leadership team to work towards the development of alternative methods including cell-based in vitro assays, in silico testing and emerging technologies including bioengineered organs, stem cell technology and more. 

While we work on that alongside the rest of the industry, the testing of new drugs and other chemicals for potential toxicity, safety and efficacy in a living organism is still - for the time being at least - an essential phase in the formulation of life-enhancing and life-saving treatments. 

If you’re interested to learn more about the types of testing we do click here, and to learn more about our approach to animal welfare click here.