B3 Developing Drugs (page 49) Flashcards
New Drugs are constently being developed, but before they can be given to the general public, what must they go through?
they have to go through a testing procedure. (there are Three main stages in drug testing).
What is the first stage in testing a new drug in preclinical testing?
In preclinical testing, drugs are tested on human cells and tissues in the lab.
You cant use human cells and tissues to test drugs that affect whole or multiple body systems, why?
testing a drug for blood pressure must be done on a whole animal because it has an intact circulatory system.
What is the 2nd step in preclinical testing?
it is to test the drug on live animals.
Why is preclinical drugs tested on live animals?
this is to test efficiacy (whether the drug works and produces the effect you’re looking for), and to find out about its toxicity (how harmful it is) and to find the best dosage (the concentration that should be given, and how often it should be given).
What is the British Law regarding any new drug testing?
the law is that any new drug must be tested on two different live mammals. (some people think it’s curel to test on animals, but ohters believe is the safest way to make sure a drug isn’t dangerous before it’s given to humans).
Also some people think that animals are so different from humans that testing on animals is pointless.
What happens after a drug that passes a test on animals?
it then gets tested on human volunteers in a clinical trial.
When clinical drugs are tested on humans, what happens first?
first, the drug is tested on healthy volunteers. (this is to make sure that it doesn’t have any harmful side effects when the body is working normally.
At the start of the trial a very low dose of the drug is given and this is gradually increased.
If the results of clinical trials tests on health volunteers are good, what happens next?
the drugs can be tested on people suffering from the illness.
Then the optimum dose if found - this is the dose of drug that is the most effective and has a few side effects.
How is a clinical trial drug tested on how well it works?
patients are randomly put into two groups. One is given the NEW DRUG, and other is given a PLACEBO (a substance tha’t like the drug being tested but doesn’t do anything).
This is so the doctor can see the actual difference the drug makes - it allows for the placebo effect (when the patient expects the treatment to work and so feels better, even though the treatment isn’t doing anything).
Why are clinical trials blind?
so the patient in the study doesn’t know whether they’re getting the drug or the placebo. (in face they’re often double-blind - neigher the patient nor the doctor knows until all the results have been gathered. This is so the doctors monitoring the patients and analysing the results aren’t subconsciously influenced by their knowledge.
What happens when the clinical trial has finished, and all results recorded, are they published?
the results of drug testing and drug trials aren’t published until they’ve been through peer review. This helps to prevent false claims.
(peer review is then other scientists check that the work is valid and has been carried out rigorously (see page 1).
What is meant by the efficacy of a drug? (1 mark)
Whether the drug works and produces the effect you’re looking for (1 mark)
Why do clinical trials of a new drug begin with healthy volunteers? (1 mark)
To make sure that the drug doesn’t have any harmful side effects when the body is working normally (1 mark).
Why must the results from drug testing be assessed by peer review? (1 mark)
To help prevent false claims about the results (1 mark).