Lecture 2: Introduction P2 Flashcards
What are the five (5) stages of drug development?
- Drug discovery
- Drug development
- Clinical trials
- Manufacturing
- Marketing application
How long does drug development take?
10 - 12 years
What is pre clinical testing?
Test the safety and effectiveness of the drug. Where Scientist will determine how it affects carcinogenicity, toxicity, mutagenicity and reproductive development.
What does IND mean in drug development?
Investigational New Drug
What happens in IND (Investigational New Drug) Application ?
This is a request from a clinical study sponsor to obtain authorization from the Food and Drug Administration (FDA) to administer an investigational drug or biological product to humans.
What does Phase I drug development test for?
the safety of the drug as well as Pharmacokinetics (ADME) and pharmacodynamics.
What does Phase II test for in drug development?
Tests safety and effectiveness of the drug
How many volunteers are used in Phase I of drug development?
Usually involves 20 – 80 healthy volunteers
How long does Phase I take in drug development?
May take a year
Who is testing done on in Phase II of drug development?
Usually about 100 – 300 patient volunteers who have the condition the drug was designed to treat.
How long does Phase II of drug development last?
Can take up to 2 years
What is done in Phase III of drug development?
The efficacy of the drug is further tested in this phase
Who is testing done on in Phase III of drug devlopment?
These are done on more patients are used, approximately 1000 –
3000.
How long does Phase III of drug development take?
May take 3 years
Where are Phase III volunteers found?
Conducted in several hospitals or clinics in different demographic locations.
What is New Drug Application (NDA)?
This is a document tht includes enough information for the FDA to determine whether the new drug is safe and effective; whether the drug’s benefits outweigh its risks; whether the proposed drug label (package insert) is appropriate; and whether the drug manufacturing standards are adequate.
How long can it take to for a NDA in drug development to be filed?
2 ½ years
What is Phase IV of drug development?
This is a post marketing trial to assess the drug in an uncontrolled, real-life situation.
What is the point of Phase IV of drug development?
To determine if the drug still does what it was proposed to do including any cases of adverse reactions.
What is drug disposition?
this is the four major events that occur once a drug has been adminstered.
The effect of a drug can be defined as….
local or systemic
What is a local reaction?
A local reaction is one that takes place at the specific site of application, such as the gastrointestinal tract (GIT) in the case of oral administration or the epithelial layer in the case of topical application.
What is systemic effects?
Systemic effects are effects that are produced at a site other than the site of application.
For example, the oral administration of an analgesic agent, which effectively applies the drug to the GIT, may influence a distant location such as the brain.
What are some mechanisms by which interaction of chemical may occur?
- Protein Binding
- Biotransformation
- Excretion
- Absorption
What are some drug interaction?
- Behavioural drug
- Pharmaceutic drug
- Pharmacokinetic drug
- Pharmacodynamic drug
What is Behavioural drug interaction ?
Interactions occur when one drug alters the patient’s behaviour to modify compliance with another drug.
What is Pharmaceutical drug interaction ?
Pharmaceutical interactions occur prior to the administration of drugs to patients and generally represent incompatibilities of drugs administered via intravenous infusion.
What is Pharmacokinetic drug interaction?
Interactions occur when one drug changes the systemic concentration of another drug, altering ‘how much’ and for ‘how long’ it is present at the site of action.
What is Pharmacodynamic drug interaction?
Interactions occur when interacting drugs have additive effects, where the overall effect is increased. Can be opposing effects, where the overall effect is decreased or ‘cancelled.
What are the types of pharmacodynamic chemical interactions ?
- Additive
- Synergistic
- Potentiation
- Antagonism
What is additive interaction effect?
This action occurs when the combined effect of two or more chemicals is equal to the sum of the effect of each agents given alone. (2+2 = 4)
What is synergistic interaction effect?
This action occurs when the effect caused when exposure to two or more chemicals at one time results in health effects that are greater than the sum of the effects of the individual chemicals. (4+5=15)
What is potentiation interaction effect?
A chemical that is usually nontoxic, becomes greatly toxic due to the introduction of another chemical (0+5=15).
What is the antagonism interaction effect?
This is the reduction of a chemicals (toxin/toxicant) effect due to the presence of another chemical (4+2=1).
What are types antagonistic interactions?
- Functional
- Chemical (Inactivation)
- Dispositional
What is Dispositional antagonistic interactions ?
Reduction of toxicity from a substance, due to alterations made to either A, D, M and/or E.
What is Functional antagonistic interactions?
Administration of one chemical counterbalances the effect of another chemical on the same physiological function.
What is chemical antagonistic interactions?
The interaction of two compounds, producing a less toxic product.
What is warfarin?
Water-soluble compound with anticoagulant properties that used as rat poison and in the treatment of thrombosis.
What is receptor antagonistic interaction?
Reduction of toxic effects due to two or more compounds binding to the same receptor.
What are the mechanism of tolerance?
- Decreased amount of toxin/toxicant reaching the target site (Dispositional Tolerance).
- Decrease responsiveness of the tissue to the chemical present.
