Moving Away From Animal Testing To Improve Vaccine Quality

Vaccines are of paramount importance in the fight against disease, and COVID-19 has recently shown us the impact that a pandemic can have. Regulations governing the testing of vaccines often require the use of animals. However, the use of animals is not always justified on scientific grounds. There are reasons to doubt the importance of animal testing: it is time-consuming, expensive, and offers high variability for low precision. Moreover, these tests pose ethical problems because the animals used often experience immense suffering before dying.

This article summarized the content of a conference held in Bangkok, Thailand, in December 2019. The aim of this conference was to discuss how to transition from in vivo to in vitro methods, and many experts and actors in the field of vaccines were present to speak. After their speeches, two workshops took place. The first one to discuss the aspects of validation, acceptance by regulators, implementation by manufacturers, and harmonization of regulatory requirements. The second addressed the difficulties that developing countries may face in making this transition.

This shift from in vivo to in vitro testing is a consequence of the application of the 3Rs described by Russell and Burch in 1959. These 3Rs aim to Replace animals with non-living models, to Reduce their numbers when they are to be used and to Refine practices to take account of their welfare. They were described to reduce animal suffering but also to increase the quality of science. 

Participants in the first workshop agreed, among other things, that validation of in vitro methods is difficult due to lack of acceptance by regulators, of knowledge to design such studies, and of materials. As solutions, they proposed to establish more guidelines, to increase international collaborative studies and data sharing, and to create a reagent bank.

The main obstacles to the acceptance of in vitro methods by regulators are that these methods are rarely included in regulatory requirement texts. In addition, there is a lack of clarity on the information that should be provided to regulators when dealing with these methods. To overcome these obstacles, participants proposed to clarify the information needed by regulators, to create a standardised dialogue between manufacturers and regulators, and to facilitate the creation of licenses.

The problems with the use of in vitro methods by manufacturers include the possibility of running out of reagents, lack of expertise on these methods, and a sometimes low interest in investing in them. To improve their harmonisation and use, participants agreed on the importance for WHO to review in vitro methods and include them in the requirements for vaccines.

Participants of the second workshop determined that some of the main obstacles in developing countries are lack of resources, of investment in these methods, and of harmonization of pharmacopoeias. They proposed to increase the participation of these countries in collaborative studies, to facilitate their access to methods and data, and to regularly harmonize guidelines and pharmacopoeias.

At the conclusion of the conference, it was pointed out that the transition from in vivo to in vitro tests will be difficult. However, the participants believe it can be achieved within the next 25 years. This transition should be done not only for animal welfare reasons, but also because the elimination of animals in testing will improve the quality of scientific output.

All actors in the field of vaccines must work together to achieve this, from authorities to manufacturers to organizations such as the WHO or the Bill & Melinda Gates Foundation. This is one of the most important points of this conference: all stakeholders must collaborate. During the transition period, and in line with the 3Rs, efforts should also be made to reduce the number of animals used and improve their conditions.

This article gives hope that animals may soon be freed from experimentation if individuals, organizations, and government bodies can cooperate. Many scientists and experts are working towards this goal. These changes are taking place to increase the quality of science, but also because animal ethics are gaining importance. This is where animal advocates can play a role. By continuing to value the rights and interests of animals, and by supporting such changes, we can accelerate the pace at which animals are no longer used.