Drug Discovery 1 Flashcards
what substances are classed as drugs ?
biopolymers and vaccines
define drug:
a single chemical substance that is conventionally marketed for use in medicine
what is not classed as a drug ?
recreational drugs because they dont have therapeutic use
herbal remedies or dietary supplements because these are poorly defined and they dont undergo the regulatory procedures which medicinal drugs do
drug wannabees which are created during the drug development process because they are not marketed for
what does drug discovery and development entail?
process of taking a therapeutic concept and converting it into a physical entity which is marketed for medicinal benefit and financial profit
it can take up to 15 years
its a mutli disciplinary challenge
what are the examples of the different disciplines involved in producing a drug ?
computational synthetic and medicinal chemistry computational biology and bioinformatics molecular biology molecular pharmacology in vivo pharmacology clinical testing and evaluation safety pharmacologists marketing patent and regulatory law process chemistry and manufacturing
what does NME stand for ?
new molecular entity
a new molecule which has been discovered to be used as a drug
what is the challenge in drug discovery and development ?
same amount of cash is being spent but there are smaller amounts of drugs being produced
the cost:success ratio is increasing
why is the cost:success ratio increasing?
because the easier drugs to develop have already been developed and because the regulations to produce drugs are much more stringent now
what are the 6 stages in the developement of a new drug ?
1- discovery - about 1500 2- clinical trial 1- 9.1 3- clinical trial 2 - 5.5 4- clinical trial 3- 1.8 5- regulation - 1.3 6- launch - 1
how many years does it take to discover a drug wannabee?
5 years
how many years do pre-clinical trials take ?
1.5 years
how many years does it take to do clinical trials?
6 years
how many years does it take to do a FDA review?
2 years
how many years does it take to manufacture the drug ?
2 years
what are the reasons for high attrition rates ?
poor efficacy poor pharmacokinetics toxicity in animal trials adverse effects in humans commerical reasons
how have the attrition rates changed between 2000 and 2008?
in 2000 there were much higher rates of attrition due to poor pharmacokinetics, with 40% of drugs failing from this, however this has significantly reduced
however in 2008 the number of drugs failing due to commercial reasons has increased - more difficult and expensive to get drugs approved and there is fierce competition
how are the attrition rates due to poor pharmacokinetics caused ?
poor effect of the body to the drug due to not getting the drug to the target and it has adverse effects elsewhere
what is the main reason for a drug failing during the clinical trials ?
2/3s is due to insufficient efficacy
1/5 is due to safety issues
what are the 4 main reasons to start/complete a drug discovery project ?
scientific reasons
development
strategic reasons
operational reasons
what are the scientific reasons to start/complete a drug discovery project?
strength of hypothesis target availability assay availability animal models chemical starting point
what are the development reasons to start/complete a drug discovery project?
competition patents toxicology clinical development production regulation
what are the strategic reasons to start/complete a drug discovery project ?
market predictions
unmet medical need
company strategy
current drug pipeline
what are the operational reasons to start/complete a drug discovery project?
resources
costs
staff expertise
company facilities
what is “translational chemistry” ?
observation that a particular substance exhibits biological activity that may be of interest…. explore link between the chemical and the activity to improve these properties
main point= there was no idea about the disease/therapy at the start- there is potential for this drug to treat any disease
what is “translational biology”?
observation of a biological property and concept that it could be manipulated for therapeutic benefit….. then the pursuit of a substance that can modulate this biology
main point= start with the biology instead of the compound - attempt to find a compound which will modulate a biological property
what is an example of translational chemistry ?
discovery of d-turbocurarine
it was a plant extract used by south american natives to attach to their arrows to immobilise their prey when hunting
“concept”- can we understand the unusual properties of this plant
“drug discovery/development”- can this understanding be developed into real life
what does d-tubocurarine?
it causes muscle paralysis
further development showed that it is a blocker of the nicotinic acetyl choline receptor at neuromuscular junctions
what have d-tubocurarine analogues been used in ?
used in open chest surgery to paralyse the diaphragm
