Regulatory project to determine the potency value associated with the manufacture of specific neurotoxin substances as required by the Regulatory Authorities
NTS Identifier
NTS-IE-113622 v.2, 04-11-2024
NTS National Identifier
Field will not be published.
Country
Ireland
Language
en
EU Submission
Field will not be published.
Yes
Project duration expressed in months.
12
Keywords
Botulinum Neurotoxin
Potency Test
Drug Substance
Regulatory requirement
Patient safety
Purpose(s) of the project
Regulatory use and routine production: Quality control (including batch safety and potency testing)
Objectives and predicted benefits of the project
Describe the objectives of the project (for example, addressing certain scientific unknowns, or scientific or clinical needs).
Biological neurotoxins are natural toxins (e.g. from bacteria) which can affect the body’s nervous system, and some types of these toxins have been developed as therapeutic medicines. The objective of this project is to determine the potency value of a biological neurotoxin used to manufacture human medicinal products. Potency testing is performed to confirm that each manufactured batch of the neurotoxin medicinal product is of a consistent strength, to ensure that it will be both safe and effective for human patients. In this project, testing using animals is required by EU medicines legislation, as currently there is no alternative (non-animal) test available and approved by EU medicines regulators to confirm the potency of this botulinum neurotoxin substance.
What are the potential benefits likely to derive from this project? Explain how science could be advanced, or humans, animals or environment may ultimately benefit from the project. Where applicable, differentiate between short-term benefits (within the duration of the project) and long-term benefits (which may accrue after the project is finished).
The regulatory testing performed under this project authorisation will allow for the continued safe development, production and use of medicines derived from botulinum neurotoxin for the treatment of a wide range of medical conditions. The potency data generated from this testing provides the manufacturer with the potency information required by medicines legislation in order for these medicinal products to be released onto the market for the treatment of a range of human medical conditions.
Predicted harms
In what procedures will the animals typically be used (for example, injections, surgical procedures)? Indicate the number and duration of these procedures.
Mice used in this study will undergo one single-step procedure. Animals will receive an injection of the test item into the abdomen, and different groups of animals will receive different doses. The injection process will take less than 1 minute per animal, however mice will remain on study for up to 3 days to allow the effects of the toxin to be assessed.
What are the expected impacts/adverse effects on the animals, for example pain, weight loss, inactivity/reduced mobility, stress, abnormal behaviour, and the duration of those effects?
The physical injection itself causes mild temporary discomfort at the time of injection however the effects of the test item may last until the end of the test, i.e. 72 hours. The animals in the lowest toxin dose groups should not experience any other adverse effects, and for these animals the severity experienced will be mild. The animals in the mid range dose groups will experience typical signs of toxicity to varying extents and are therefore expected to experience moderate severity. A small percentage of animals in the highest toxin dose groups could potentially experience significant signs of toxin related impairment and possible death, and could therefore potentially reach severe severity. However, early humane endpoints will be applied which will mean that most animals will be humanely euthanised before reaching this point, so the number of animals experiencing a severe severity will be kept to an absolute minimum.
What species and numbers of animals are expected to be used? What are the expected severities and the numbers of animals in each severity category (per species)?
Species
Total number
Estimated numbers per severity
Non recovery
Mild
Moderate
Severe
Mice (Mus musculus)
7686
0
2709
3096
1881
What will happen to the animals kept alive at the end of the procedure?
Species
Estimated numbers of animals to be reused, to be returned to habitat/husbandry system or to be rehomed
Reused
Returned
Rehomed
Please provide reasons for the planned fate of the animals after the procedure.
Animals will be humanely euthanised at the end of the test period as they cannot be resused for any other purpose due to having received an injection of botulinum neurotoxin.
Application of the Three Rs
1. Replacement
State which non-animal alternatives are available in this field and why they cannot be used for the purposes of the project.
The manufacturers have invested heavily in the research and development of a non-animal alternative test i.e. a cell-based potency assay (CBPA) for neurotoxin testing. This CBPA is already in use for safety testing of the final marketed medicinal product, however it has not yet received regulatory approval for testing this neurotoxin drug substance (drug substance is the raw material used to manufacture botulinum toxin medicinal products). Therefore, potency testing using mice is required in the interim, until approval to use the CBPA to test drug substance is granted.
2. Reduction
Explain how the numbers of animals for this project were determined. Describe steps that have been taken to reduce the number of animals to be used, and principles used to design studies. Where applicable, describe practices that will be used throughout the project to minimise the number of animals used consistent with scientific objectives. Those practices may include e.g. pilot studies, computer modelling, sharing of tissue and reuse.
Statistical methods were used to ensure the minimum numbers of animals are used. Test group sizes were determined in earlier studies by the client and are determined based on the legal requirements of the European legislation. No further reduction is currently possible.
3. Refinement
Give examples of the specific measures (e.g., increased monitoring, post-operative care, pain management, training of animals) to be taken, in relation to the procedures, to minimise welfare costs (harms) to the animals. Describe the mechanisms to take up emerging refinement techniques during the lifetime of the project.
The main refinement in this study is the application of early humane endpoints. Animals will be monitored frequently and any mice that are likely to experience severe effects will be removed from study at an early timepoint and humanely euthanised. This will shorten the duration of suffering and distress that animals would otherwise experience. If any additional refinement techniques that do not interfere with the robustness or validity of the test emerge during the course of this project they will be incorporated into the project protocol.
Explain the choice of species and the related life stages.
Adult mice are used because this is the species required in the European regulatory legislation for this type of testing.
Project selected for Retrospective Assessment
Project selected for RA?
Deadline for RA
Reasons for retrospective assessment
Contains severe procedures
Uses non-human primates
Other reason
Explanation of the other reason for retrospective assessment
Additional fields
National field 1
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National field 2
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National field 3
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National field 4
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National field 5
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Project start date
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Project end date
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Project approval date
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ICD code 1
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ICD code 2
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ICD code 3
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Link to the previous NTS version outside the EC system