B2 Developing New Medicines Flashcards
(23 cards)
What is the first step in developing a drug?
A target that the drug will act upon needs to be identify
When developing a new drug what is the target likely to be?
A gene or protein that is linked to the development or progression of the disease.
Give an example of a target.
For an anticancer drug it might be an enzyme that is linked to tumour formation.
How can targets be identified?
By studying the genomes and proteins of plants and animals.
Study the genomes and proteins of pathogens to identify targets.
Give an example of how studying genomes can help to identify targets.
Studying the genomes of people with and without Alzheimer’s disease might lead to the discovery of certain gene variants that contribute to the disease.
Once a target has been identified what do scientists do next?
Find a chemical substance that will have the effect they want on the target.
How do scientists find a chemical substance to use on a target?
Large libraries of chemical substances have to be screened using a very high tech process, to assess their likely effectiveness.
The result of screening is unlikely to find a substance that will work exactly in the way they want.
As a result of screening what happens to the most promising chemicals?
They are selected and modified and undergo further tests
Name two types of testing used in developing potential drugs.
Preclinical testing and clinical testing.
What happens in preclinical testing?
First drugs are tested on cultured human cells.
Second step testing drug on live animals.
Both of these steps are used to see if the drug is effective and to find out how safe it is.
What are cultured human cells?
Human cells That are grown in a lab
What kind of drugs cannot be tested on cultured human cells?
Drugs that affect whole or multiple body systems e.g. a drug for blood pressure.
When a drug had passed animal testing what is the next step?
A clinical trial on human volunteers.
First the drug is tested on healthy volunteers to make sure that it is safe (no harmful side effects when the body is working normally)
Successful drugs are then tested on people with the disease to test it’s effectiveness and safety.
How do clinical test allow for the placebo effect?
Patients are randomly put into two groups one group is given the drugs the other is given a placebo.
What is a placebo?
A substance that looks like the drug being tested but doesn’t do anything e.g. a sugar pill.
Why do clinical tests use a placebo on some patients?
To allow of the placebo effect. This is when the patient expects the treatment to work and so feels better every thought the treatment isn’t doing anything.
What are the ethnical issues around giving a placebo?
Giving a placebo to a patient with the disease rather than any treatment especially the symptoms are severe e.g. death
Some trials don’t use placebos.
What is a blind trail?
The patient in the study doesn’t know whether they are getting the new drug or a placebo but the doctors do.
What is a double blind trail?
The doctors and the patients don’t know whether they are getting the new drug or a placebo until all the results have been gathered.
Why are double blind trails used?
The doctors aren’t subconsciously influenced by their knowledge.
What is an open label trial?
The doctors and the patients are aware who is receiving the drug
Why use open label trial?
Used in comparing the effectiveness of to very similar drugs.
Explain how a double blind trial would be carried out. (2 marks)
In a double bind trail patient are randomly put into two groups. Some receive the drug, some receive the placebo. (1 mark)
The doctors and the patients don’t know if they are receiving the drug or a placebo until all results have been gathered. (1 mark)
