Veterinary drug delivery Flashcards
why is veterinary drug delivery relevant to NZ?
- NZ is home to 30.8million sheep
- NZ’s dairy cattle population is more than 6.6 million (in 2013)
What are the differences in veterinary pharmaceutical drug development vs. drug development for humans?
- The formulation design is the same quality.
- contemporary pharmaceuticals are equal
- the quality of veterinary pharmaceuticals are no less than humans
- human safety is part of the development process
- advanced veterinary pharmaceuticals can be species specific
- companion animals are a growing market similar to paediatrics
What are the benefits with veterinary pharmaceutical innovation?
- gastro retention of veterinary pharmaceuticals have been exploited for decades
- long term delivery of drug provides decreased costs and improved efficiency for farmer.
What are the regulatory differences between veterinary pharmaceuticals and human pharmaceuticals?
- phase 1 trials are considered rapid as the pre-clinical test animal is the target animal for the drug
- In the USA, their centre for veterinary medicine is part of the FDA. In NZ, we have an NZ agricultural compounds veterinary medicines which is part of the NZ food safety authorities.
- The NCE must address environmental conditions as human safety is important due to being part of the food chain.
- special terms used in veterinary pharmaceuticals
- manufactured to GMP standards
What are the special terms used in veterinary pharmacueticals?
- there is a witholding time/period that must be met
- there is a maximum residue level of substances which must be followed
What are the MRLs?
-maximum residue levels are the upper legal levels of a concentratin for drug residues in a specific tissue for food, such as muscle or milk
What are MRLs also known as?
- minimum levels
- this refers to the MRLs for agricultural and veterinary chemicals in agricultrual produce, especially for produce entering the food chain
What is the witholding time/period?
-the WHT refers to the minimum period of time that must elapse between the last treatment of an animal with a veterinary medicine and the supply of products (in meat or milk) from those animals for food consumption
What does the WHT depend on?
- drug/product dependent
- animal species/tissue dependent
What are the 5 major factors for the need of new drug delivery technology for animal health?
- enhance consumer convenience and compliance
- improve pharmacokinetics of drugs
- extend patent life of proprietary molecules
- provide product differentiation
- assure target animal and consumer safety.
What forms of veterinary pharmaceuticals are there?
-various devices such as tablets, capsules, gels, powders and liquids
What is different about veterinary injectable products?
- admin is different than for human
- it is the preferred admin route in veterinary practice
- animal health industry has generated strong interest in long term drug delivery for both companion and farm animals
What long acting injectable products are there?
-the formulation principle is the same as for humans
-for controlled release: can be
dissolution controlled depot
adsorption type depot
partition controlled depot
esterification type depot
encapsulation type
in situ solidifying depots
What are two unique routes of delivery which are common for veterinary pharmaceuticals
- intraruminal (into the cow’s stomach)
2. intramammary (into the cow’s udder)
What are intraruminal boluses?
-drug delivery devices designed to provide long-term delivery of drug to the rumen compartments of ruminant animals
What are the results of intraruminal boluses?
- long term deliver (>100 days)
- retained in the rumen by geometry or density
What is a rumen?
- essentially one of the compartments in the stomach of grazing animals
- their GIT reflects a diet high in fibre but low in fat and protein
- they are known as ruminant animals