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Frequently Asked Questions on the EURL ECVAM Recommendation on Non-Animal-Derived Antibodies

1. Where can I find the EURL ECVAM Recommendation on non-animal-derived antibodies and what does it include?

The EURL ECVAM Recommendation is available to download from the EU Science Hub. It comprises the Recommendation itself and the ESAC Opinion on the "Scientific validity of replacements for animal-derived antibodies" (Annex 1) and an ESAC Working Group report (Annex 2).

2. What does the EURL ECVAM Recommendation on non-animal-derived antibodies state?

In a nutshell, the EURL ECVAM Recommendation on non-animal-derived antibodies recommends that "animals should no longer be used for the development and production of antibodies for research, regulatory, diagnostic and therapeutic applications. In the EU, the provisions of Directive 2010/63/EU should be respected and EU countries should no longer authorise the development and production of antibodies through animal immunisation, where robust, legitimate scientific justification is lacking".

3. Does the EURL ECVAM Recommendation impose a ban on the use of animals for the development and production of antibodies?

No, the EURL ECVAM Recommendation does not impose a ban, nor is it proposing a ban per se. In the context of the authorisation of projects involving the use of live animals, the Recommendation simply calls for proper adherence to the legal obligations adopted under Directive 2010/63/EU on the protection of animals used for scientific purposes. The Directive (Article 38) requires a case-by-case scrutiny of project proposals to ensure that only when there is robust and legitimate scientific justification for the use of animals a project should be authorised. This obviously applies to projects involving the development and production of antibodies too. It is the responsibility of Member State competent authorities to assess and determine when such justification may exist to ensure that Directive obligations are complied with.

4. What is a EURL ECVAM Recommendation?

A EURL ECVAM Recommendation provides the views of the JRC's EU Reference Laboratory for alternatives to animal testing (EURL ECVAM) on the scientific validity of alternative test methods. Recommendations also advise on applications of alternative methods, any potential implications for stakeholders, and follow-up activities to promote alternatives and address knowledge gaps. During the development of its Recommendation, EURL ECVAM typically mandates the EURL ECVAM Scientific Advisory Committee (ESAC) to carry out an independent scientific peer review of available evidence, which is communicated as an ESAC Opinion and Working Group report.

5. Were stakeholders consulted on the EURL ECVAM Recommendation?

The EURL ECVAM Recommendation underwent a broad stakeholder consultation prior to its publication. Following usual procedure, EURL ECVAM consulted with: Commission services and relevant EU Agencies; EURL ECVAM’s advisory body for Preliminary Assessment of Regulatory Relevance (PARERE), that involves all Member States of the European Union; partner organisations of the International Collaboration on Alternative Test Methods (ICATM) including USA, Canada, Japan, South Korea and Brazil; ESAC; and the EURL ECVAM Stakeholder Forum (ESTAF), where various non-governmental stakeholder organisations are represented, including several industry sectors such as cosmetics, chemicals and pharmaceuticals.

6. On what scientific evidence is the EURL ECVAM Recommendation based?

EURL ECVAM mandated the EURL ECVAM Scientific Advisory Committee (ESAC) to review the scientific validity of non-animal-derived antibodies and non-antibody affinity reagents used in research and in regulatory and diagnostic fields. Based on its independent scientific peer review, the ESAC produced an Opinion on the "Scientific validity of replacements for animal-derived antibodies" (Annex 1 of the Recommendation), supported by an ESAC Working Group report (Annex 2).

7. What is the ESAC Opinion on the scientific validity of replacements for animal-derived antibodies?

In brief, ESAC concluded that: non-animal-derived antibody are mature reagents generated by a proven technology; non-animal-derived antibodies offer significant additional scientific benefits; non-animal-derived antibodies should be promoted; non-animal-derived antibodies are able to replace animal-derived antibodies in the vast majority of applications; well characterised, recombinant affinity reagents will improve the reproducibility of science and positively impact society.

8. What is ESAC and how does it work?

ESAC is the EURL ECVAM Scientific Advisory Committee. It is a formally registered expert group of the European Commission that provides independent advice to the EURL ECVAM on scientific matters related to the protection of animals used for scientific purposes. Members of ESAC and ESAC Working Groups must act independently of any external influence and solely on the basis of scientific considerations. The functioning of ESAC is defined by its Terms of Reference and its Rules of Procedure.

9. Why does the EURL ECVAM Recommendation also cover antibodies intended for therapeutic use?

The EURL ECVAM Recommendation also covers antibodies for therapeutic use, although ESAC was not explicitly requested to cover this particular application domain in its scientific peer review because of potential conflicts of interest with some members of the Working Group. However, the use of non-animal-derived antibodies for therapeutic applications is already well established, as evidenced by the availability of market-approved therapies based on non-animal-derived antibodies and specific mention of them in relevant guidelines of the European Medicines Agency (EMA). Moreover, the main arguments set out in the ESAC Opinion for the scientific validity of non-animal-derived antibodies are considered universal in nature and therefore relevant irrespective of the application domain.

10. How many animals are used in the EU for developing and producing antibodies?

Until 2021, statistical data on the use of animals for scientific purposes are collected in line with the Commission Implementing Decision 2012/707/EU. At present, animals used for the development of antibodies are reported across several, more general, use-categories. For example, if an antibody is intended to be used for human cancer research, animals used for its development would be reported in the category “Human cancer”, together with other animals used for human cancer research but for different procedures. Thus with the current statistics, in the context of basic and applied research, it is not possible to distinguish between animals used for antibody development and other purposes. With regard to routine production of antibodies, only mice used for the production of monoclonal antibodies with the ascites method are reported separately, numbers being 27,333 mice in 2015 and 45,024 in 2017. Other methods for routine production of antibodies are included in two categories “Blood based products” and “Other products”. Therefore, it is currently not possible to give exact numbers. However, based on an analysis made by ESAC experts, the total number of animals used for the development and production of antibodies is estimated to be in the order of 1 million animals per year in the EU.

11. Are non-animal-derived antibodies as good as animal-derived antibodies?

According to the ESAC Opinion (see Annex 1 of the Recommendation), non-animal-derived antibodies are not only equivalent to animal-derived antibodies, but in many respects can offer significant scientific advantages and economic benefits. Important scientific advantages include: (1) non-animal-derived antibodies are sequence-defined and can therefore be duplicated with identical binding and specificity profiles forever; (2) the in vitro antibody selection against a target antigen can be tightly controlled to enrich clones with desired properties. For example, one can do the affinity selection with the exact biochemical conditions under which the antibody will be used afterwards, and therefore, select only antibodies that are functional under these conditions; (3) the genetic sequence can be modified to add a multitude of features including a variety of antibody formats and detection systems; (4) the selection of antibodies using a universal recombinant library can be performed in a few weeks, while the development of animal-derived monoclonal antibodies through immunization needs several months.

12. Are non-animal-derived antibodies a scientifically valid technology to replace animal-derived antibodies?

According to ESAC (see Annex 1 of the Recommendation), non-animal-derived antibodies are able to replace animal-derived antibodies in the vast majority of applications.

13. Are well characterised non-animal derived antibodies actually available?

The general commercial availability of non-animal-derived antibodies is currently much less than those derived from animals. Without a demand, there is no supply. Companies selling antibodies will need to look into how they will transfer to new technologies and project applicants will have to make provisions in their budgets and work programme to secure availability of the antibodies they need (see also reply to question 14).

14. Why aren't most scientists already using non-animal derived antibodies?

Unfortunately the uptake of non-animal alternatives by the scientific community is quite slow. Reasons for this include a general lack of awareness and poor scientific and technical understanding of non-animal techniques to develop or produce antibodies. There is also a misperception that non-animal derived antibodies are of inferior quality (see question 11). In addition, limited commercial availability and higher costs are commonly cited as obstacles for their use. Although economic factors do not justify the use of animals instead of a scientifically valid alternative, as reported in the ABCD (AntiBodies Chemically Defined) database for example, it only costs an academic researcher about €200 to obtain an existing recombinant antibody in only 2-4 weeks. This particular database contains approximately 21,000 different antibodies recognising over 3,000 different antigens. If the antibody is not listed in the database but there is a hybridoma available, it costs about €500 to sequence it to produce a defined recombinant version in vitro. If a sequence is not available and cannot be obtained, it costs about €2,000 to develop a completely new antibody. These are very reasonable prices in line with what researchers pay for catalogue antibodies derived from animals but, by using these services, researchers can obtain defined reagents that will be available indefinitely.

15. Where can I read more about the science behind the issue?

Articles directly related to the EURL ECVAM Recommendation and the ESAC Opinion that have appeared in prominent peer-reviewed scientific journals include:

  • Gray, A.C., Bradbury, A.R.M., Knappik, A. et al. Animal-derived-antibody generation faces strict reform in accordance with European Union policy on animal use. Nat Methods 17, 755–756 (2020). doi:10.1038/s41592-020-0906-9
  • Gray, A., Bradbury, A.R.M., Knappik, A. et al. Animal-free alternatives and the antibody iceberg. Nat Biotechnol 38, 1234–1239 (2020). doi:10.1038/s41587-020-0687-9

Reports from other sources that partly deal with scientific aspects related to antibody development and production have been published by the League of European Research Universities (find it here) and jointly between the European Animal Research Association and the European Federation of Pharmaceutical Industries and Associations (find it here).

16. Where can I learn more about non-animal-derived antibodies?

There is a wealth of scientific literature describing various approaches for generating non-animal-derived antibodies, for example building of universal recombinant antibody gene libraries, antigen selection and production, as described in Annex 2 of the EURL ECVAM Recommendation. Furthermore, the following resources are freely available: