GRADE C• Describe the main steps in testing a new drug.• Explain the terms placebo and double-blind trial.

Drug Testing

Scientists have developed a new medicine what features would be important?

1. Effective – it must prevent or cure a disease or at least make you feel better.

2. Safe – the drug must not be too toxic (poisonous) or have unacceptable side effects for the patient.

3. Stable – you must be able to use the medicine under normal conditions and store it for some time.

4. Successfully taken into and removed from your body – it must reach its target and be cleared from your system once it has done its work.

Why is it important to test new drugs before they are released for general use?

If these tests are not thorough then a new medicine may have dangerous side effects

Thalidomide is a medicine that was widely used in 1950s as a sleeping pill.

It also helped to prevent ‘morning sickness’ in pregnant women.

It was not tested thoroughly enough before been marketed, women started to give birth to babies with severe limb abnormalities.

It is no longer used for pregnant women but it is effective in treating leprosy

Thalidomide

What kind of drugs are we looking at developing?

What is the leading cause of deaths between 25-74 yr olds in

the UK?

Cancer is the biggest premature killer

4 in every 10 people between ages 25-74 are killed by cancer before they reach their life expectancy.

How much do you think it costs pharmaceutical companies

annually to test each new drug?

The annual cost for clinical trial for each drug is £600 million PER DRUG

Drugs are first tested in lab using cells, tissues and living animals.

Tested in clinical trials using healthy volunteers & patients. Initially small doses of the drug are used.

If no side effects are seen further trials are used to find the optimum dose for the drug.

Answer these questions!

What is a placebo?This is sometimes given to the control group. It looks exactly like the real treatment but has no drug in it

What is a double blind trial?Neither the patient of the doctor know whether the patient is in the control group or not

How do they maintain a fair test during a clinical drug trial?

Animals of each type used in research in 2005

Total number of animals used =

2.89 million

Other mammals includes:

Monkeys 4652Dogs 7670Sheep 29,329Cats 500

WHY MICE?

Genetic engineering to test for obesity geneLeptin, the Appetite Hormone, Rewires the Brain

Leptin promotes the growth of mouse neurons. Images show growth patterns without leptin (top) and with leptin.

Mice without the leptin gene are morbidly obese (left) compared to normal mice (right).

How do you fell about animal testing? Try to give positives and negatives.