11 -Pesticides Biologics Monoclonals Flashcards
Drugs vs. pesticides
- Compounds used in vet intended for use against external organism=can be classified as either a drug OR pesticide
- Authorization for sale is granted by Health Canada
o Drugs=Veterinary Drug Directorate
o Pesticides=Pest Management Regulatory Agency
o *regulations are total different - *look at if it is a DIN or pest control product (PCP) number
What are the primary differences for vets when prescribing/selling drugs and pesticides?
- Can’t LEGALLY use pesticides extralabel!
- Need to have label instructions on in=can NOT dispense a partial package
- *why differences: margin of safety and therapeutic window
o Pesticides are riskier - DIN vs PCP (pest control product)
Why are veterinary DRUG products that have effects on external arthropods/insects not pesticides?
- Systemic absorption!
- NOT just topical effect
Veterinary Pesticide examples
- Advantage (Bayer) = pesticide
- Advantage Multi (Bayer) = DRUG (endoparasiticide)
Pesticide formulations
- Usually some type of topical administration
o Ear tags
o Collars
o Immersion baths
o Topical dusts
o Shampoos
o Premises application - *Occupational exposure risks
Veterinary biologics
- Covers vaccines, antitoxins, diagnostic test kits and some antibody formulations used to treat/prevent INFECTIOUS diseases in animals
- Regulated by Health Canda, but under the CFIA
‘large molecule’ drugs
- Products that have a larger molecular weight than typical drugs based on chemical API
- Can be small peptides or larger protein
Examples of ‘large molecules’ drugs
- Hormones (ex. insulin, GH)
- Colony-stimulating factors (G-CSF)
- Antibodies
- Enzymes
‘large molecule’ drugs can be produced by
- Harvesting natural sources (ex. porcine pancreatic enzymes)
- Recombinant technology (ex. derived from bacteria genetically modified to overproduce the protein)
**generally MUCH more EXPENSIVE to synthesize than traditional (small molecule) drugs
Monoclonal antibodies
- Any drug name with ‘vetmab’ at the end
- Antibodies produces synthetically with extremely high specificity for a specific antigen
- Not produced by B cells or plasma cells in the host animal
How are mAbs different from ‘regular’ antibodies?
- More precise replicas (a clone of a single antibody)
Can the same monoclonal antibody be given to multiple species?
- No, structure of target antigen differs slightly between species
- Ex. Y structure
o Fab ‘arms’ (antigen binding fragment
o Fac ‘stems’ (crystallizable structure)
What do monoclonal antibodies target?
- All sorts of antigens!
o Bind to and inactivate the protein/receptor
o Can lead to apoptosis in certain cases
What are some specific targets for mAbs?
- Growth factors
- Cytokines (ex. IL-31)
- Antigens on tumor cells (human mAbs)
How are mAbs administered?
- Since they are proteins=parenteral injection (SC in vet med, IV for some humans)
- NOT orally
Why can mAbs NOT be administered orally?
- They are proteins!
- *need them intact otherwise they will not work
How long is the mAb effect?
- Tends to last one month (low clearance (metabolism))
- Can have chemical moieties attached to decrease the rate of clearance (increase half-life)
o Ex. PEGylated proteins with Polyethylene Glycol attached
Is there a risk of host immune response if mAb is repeatedly administered?
- Not so far
