Bioinorganics Flashcards
What is a drugs’ Affinity?
Affinity is how well the compound binds to the target.
What is a drugs’ Efficacy?
The maximum effect or percentage of the maximum effect of the drug.
What is a drugs’ selectivity?
Selectivity is how compound specific the drug is.
What is a drugs’ potency?
Potency is the concentration at which the drug starts working. High potency = Low concentration
Describe target based drug discovery.
Target based drug discovery is the main approach to treating diseases. A drugable target thought to be uniquely associated to the disease of interest is identified then validated to confirm that modulation will have an effect.
During preclinical tests what are acute and chronic referring too?
Preclinical tests are done on cells and acute is exposing the cells to high doses of drug for a short time while chronic is exposing them to low doses for a long time.
What are some causes for drugs to fail and their relative occurrence?
Most clinical candidates fail during phase 2 clinical trials.
Previously unknown toxic side effects 50%
Insufficient efficacy against the disease 30%
Poor commercial viability 15%
What is Log-P?
Log-P = Partition coefficient = a measure of molecular “Greasiness” and is generally the most important property in drug discovery.
As molecular weight increases the Log-P generally increases.
As the # of H-bond acceptors/donators increases the Log-P increases.
What problems do drugs encounter if they are too lipophilic?
When taken orally they have poor absorption in the gut, dissolves into fat globules.
Intravenously it will have poor solubility in blood and be taken up by fat tissues. It is also likely to be promiscuous, have uncontrollable off target binding and produce toxic metabolites.
What problems will a drug have if it is too hydrophilic?
Orally it cannot pass through cell membranes including in the gut.
Intravenously it’s prone to binding to plasma proteins. It is also rapidly metabolised to produce metabolites.
