How do veterinary medicines get to market?

How it works

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We use veterinary medicines in animals for their benefits (i.e. to prevent or treat disease). However, medicines can also cause harm – to the animal being treated, to the person handling the medicine or to the environment. This potential to cause harm is the reason why medicines are regulated. Therefore, before a company can promote and sell a medicine for use in animals in the UK, it must get a marketing authorisation (also known as a product licence) from a regulatory authority. This module explains what is involved in the licensing of veterinary medicines in the UK.

By doing this module you will learn:

  • what is and what is not legally a veterinary medicine

  • what is meant by a marketing authorisation

  • what information is available on a licensed medicine and where to find it

  • how safety is monitored and how to report adverse events.

The precise legal definition of a veterinary medicine is set out in The Veterinary Medicines Regulations 2013. It is  

any substance or combination of substances presented as having properties for treating or preventing disease in animals; or 

any substance or combination of substances that may be used in, or administered to, animals with a view either to restoring, correcting or modifying physiological functions by exerting a pharmacological, immunological or metabolic action, or to making a medical diagnosis.” 

So, a product may be a veterinary medicine because it falls within the first part of the definition and is medicinal by presentation; that is, the way it is presented gives the averagely well-informed consumer the impression that it treats or prevents disease. This may be through product labels, leaflets or other literature, or adverts or oral recommendations relating to the product issued before, during or after the sale. 

Or, a product may be a veterinary medicine because it falls within the second part of the definition and is medicinal by function.

The definition applies equally to medicines that contain synthetic chemicals (e.g. paracetamol or meloxicam) or herbal substances (e.g. tee tree oil or cannabis extract) or food supplements (nutraceuticals, e.g. glucosamine, alpha-casozepine). If a product is claimed to treat or prevent or diagnose a disease in animals, or contains a substance known to have an effect on bodily functions, then it is a medicine and needs a licence. 

Example: The example of cannabidiol (CBD), a constitutent of the cannabis plant, helps to illustrate this. In September 2018 the Veterinary Medicines Directorate (the government body that regulates veterinary medicines in the UK) stated that it considered veterinary products containing CBD to be veterinary medicines on the basis that they fulfil the second part of the legal definition of a veterinary medicine. This means that without a marketing authorisation it is illegal to sell, supply or advertise CBD products for animals, with or without specific treatment claims. [Related module: CBD for canine arthritis].

If a company wants to market a veterinary medicine, there are several different ways to get a marketing authorisation, depending on where it wants to market the product:

  • Via the European Medicines Agency for a European-wide licence

If a company wants to market a product throughout the EU, then it may decide to apply for a European licence from the European Medicines Agency. This route is usually used for applications for medicines that contain new active substances (also known as new chemical entities). Examples include grapiprant (Galliprant), imepitoin (Pexion) and oclacitinib (Apoquel).

  • Via a single regulatory authority in a single country

If a company only wants to market a product in a single country, it can apply for a marketing authorisation from the regulatory authority in that country. In the UK, applications are made to the VMD. It then issues marketing authorisations, which are only valid in the UK. 

  • By application to several countries at once 

If a company wants to market a product in several EU member states, but not the whole of the EU, it can apply to several member states, one of which takes the lead in the assessment. If successful, it results in identical national licences being issued in each state involved in the application. The outcome is an identical marketing authorisation in each member state issued by its national regulatory authority (the VMD in the UK). 

  • Extending a licence to a different European member state – by mutual recognition

If a company already has a marketing authorisation for a product in one member state, it can apply for authorisation in other member states. The other member state(s) is asked to mutually recognise the original marketing authorisation. Examples of products authorised by mutual recognition include Tralieve and Tramadog (both containing tramadol); and Eradia, Metrobactin, Spizobactin (all products containing metronidazole). These were originally authorised in the Netherlands and became authorised in the UK by mutual recognition of the Dutch authorisation.

  • Provisional marketing authorisations in exceptional circumstances

Occasionally, when a new medicine is needed urgently (for example a need for a vaccine to control bird flu), a provisional marketing authorisation may be granted in the UK. This is a faster route for getting access to a medicine, usually by forgoing the need to provide the usual amounts of supportive information. This is usually only done when there is no suitable authorised medicine available to treat a particular disease or to treat a new disease in the UK. An exceptional marketing authorisation is intended to exist only for a short time and may be subject to special conditions. 

To apply for a marketing authorisation, a company must supply evidence to prove the quality, safety and efficacy of the product. This amounts to a great deal of detailed scientific information. 

To demonstrate quality, the company must show that the product can be manufactured consistently and to a high level of quality. The company must also show that the product is stable under the recommended storage conditions. 

If a company is applying for a marketing authorisation for a completely new medicine (containing a new active ingredient) the company needs to provide all the information on the product’s safety and efficacy. This usually means that the company must conduct detailed tests and clinical trials, including finding out about the safety of the product when handled and about potential risks to the environment, as well as tests to find out the effective dose, and clinical trials to test how effective the product is when used to treat animals with the condition for which it is intended, and to find out about the side effects.

Authorisations are issued to companies once they have demonstrated that the product is of the appropriate quality, can be used safely and will be effective when used in accordance with the product information. In deciding whether to licence a new treatment, the regulatory authority must judge whether the benefits outweigh the associated risks and decide whether the adverse effects are acceptable. 

An authorised product has an authorisation number preceded by the symbol Vm on its product literature (e.g. labels). A product with a European authorisation will not have the Vm symbol on its product literature; instead it carries an identifier with an EU number - e.g. EU/2/01/011/001.

Completely new products are allowed a period of exclusivity once they are marketed, usually for around 10 years. This means that no other company is allowed to copy the product during that time without permission. After the period of exclusivity has ended, other companies may produce copies of the product. These are called generic medicines. 

A generic medicine is a product that is developed to be equivalent in safety and efficacy to a medicine that has already been authorised. It contains the same active ingredient as the original medicine, and is used at the same doses to treat the same diseases. However, a generic medicine’s inactive ingredients, brand name, appearance and packaging can be different from those of the original medicine. Generic medicines are manufactured according to the same quality standards as all other medicines. 

For example, the product Frontline was the original brand of fipronil spot-on for cats and dogs. Now there are umpteen other brands of fipronil spot-on (e.g. Alfamed, Effipro). Another example is Metacam, the original brand of the drug meloxicam in oral suspension for dogs. Now there are many other brands of meloxicam oral suspension (e.g. Inflacam, Loxicom, Rheumocam)

The regulatory authority also decides the legal supply category of the product. This determines the route by which the product can be supplied. There are four supply categories for veterinary medicines in the UK:

  • Prescription Only Medicine–Veterinarian (POM-V). These may only be prescribed by a vet and may be supplied by a vet or pharmacist.

  • Prescription Only Medicine–Veterinarian, Pharmacist, Suitably Qualified Person (POM-VPS). These may be prescribed and supplied by a vet, pharmacist or SQP 

  • Non-Food Animal–Veterinarian, Pharmacist, Suitably Qualified Person (NFA-VPS). These may be supplied without a prescription by a vet, pharmacist or SQP. 

  • Authorised Veterinary Medicine–General Sales List (AVM-GSL). These may be supplied by anyone from any retail outlet. 

The VMD product information database includes a list of all veterinary medicines authorised in the UK (around 2,700 in total) and indicates the legal supply category for each. The supply category for products can also be found in the NOAH Compendium, although this database does not include all authorised veterinary medicines. 

Some products are allowed to be marketed for small pet animals without the need for a marketing authorisation. This is because it is recognised that it can be difficult to gather sufficient evidence for marketing authorisations for these uses. This includes products for:

  • aquarium animals

  • caged birds

  • homing pigeons

  • terrarium animals

  • small rodents

  • ferrets

  • rabbits.

However there are certain conditions for marketing products in this way: the products can only contain certain authorised ingredients; the products must be manufactured to high standards; they must only be for administration by mouth or to the skin or, for fish products, by addition to water; and only be sold in pack sizes that are for a single course of treatment. The label must state that the product is exempt from the statutory requirement for a marketing authorisation. Examples include Anti-parasite spot-on for hamsters and gerbils (which contains ivermectin) and Lapizole suspension for rabbits, birds, reptiles and ferrets (which contains fenbendazole).

These products are included in the NOAH Compendium. Under legal classification these products are categorised as SAES (Small Animal Exemption Scheme). The products are not in the VMD’s product information database because they are not authorised veterinary medicines.

All authorised medicines (including generics) have a summary of product characteristics (SPC). This sets out how a medicine should be used, and the effects (including adverse effects) it may have on animals (and on humans and the environment). The VMD product database has links to the SPCs of all veterinary medicines licensed for use in the UK.

The SPC is a legal document. It is drafted by the company applying for authorisation to market the medicine, but the wording must be approved by the regulatory authority (the VMD or the EMA). The SPC is a summary of what has been agreed about the product as a result of the regulatory authority’s assessment, and is based on the clinical trials done during the development of the product.

The clinical trials that are done before a medicine is authorised are usually not large enough to detect all potential adverse effects (particularly rare effects) or to show the true frequency of adverse effects. Therefore continued monitoring of drug safety after marketing is crucial for detecting adverse effects that have not been picked up in clinical trials, or for detecting adverse effects that only occur in certain breeds or groups of animals, and for tracking the frequency of known adverse effects. In the UK, the VMD collects voluntary reports of suspected adverse reactions to veterinary medicines from veterinary professionals, pharmaceutical companies and the general public. The scheme collects reports on licensed and unlicensed veterinary medicines, and human medicines used in animals, including: 

  • those occurring after authorised or unauthorised use

  • those associated with suspected lack of efficacy

  • human reactions to veterinary medicines

  • environmental problems.

A suspected adverse reaction to a veterinary medicine can be reported using the VMD’s online reporting site. All reports received by the VMD are recorded on a database, and all are acknowledged. Single reports do not usually result in action by the VMD. However, if a pattern of adverse events for a specific product emerges, regulatory actions to improve the safety of that product are taken depending on how serious they are. Such actions include:

  • adding warnings to the product information

  • changes to the authorised use of the product

  • product or batch recall

  • suspending the product from the market until the safety issues are resolved

  • suspending the right to manufacture the product. 

For example, after receiving reports of seizures with Bravecto (fluralaner), a parasiticide used in dogs, the EMA concluded in July 2017 that the medicine continues to have an acceptable safety profile. However, the company that markets the product was told to update the package leaflet (within 6 months) and include seizures as a new side effect that is reported very rarely (that is, in less than one animal out of 10,000 animals treated). Vets and pet owners have also been advised to use Bravecto with caution in dogs with epilepsy.

We can be confident that a licensed veterinary medicine:

  • contains the amount of active drug(s) that is stated on the label

  • has been shown to work when used in accordance with the licence (i.e. for the specified species, condition and according to the dose and instructions for use)

  • is safe to use as recommended.

  • the safety is constantly monitored.


If you prefer, you can listen to the whole audio presentation of this module using the following podcast. Don't forget that you can also download the podcast to your iPod, music player, tablet or smartphone using the Download link on the right of the audio player.

How we produced this module

Our modules start with a detailed outline and electronic literature search. We then commission a collaborating author to draft the text of the module. The collaborating author on this module was Helen Barnett. The draft is circulated unsigned to a wide range of commentators, including practising first-opinion vets, topic specialists, the companies that market any mentioned drugs and other organisations and individuals, as appropriate. They can raise points about the interpretation of evidence, ask questions that are important to clinical practice, and present alternative viewpoints. There is a rigorous editing and checking process and the result is a module that is evidence-based, impartial and relevant to clinical practice. The final module is unsigned because it is the result of collaboration. 


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