AQA Biology 4.3.1.9
Drug discovery and development
A new drug has to pass gate after gate before anyone can be prescribed it. Follow one through.
Triple Science · Higher tier
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Who went first?
Every medicine in a pharmacy was once brand new, and nobody knew whether it was safe.
If you had to guess, was it tested on people first, or on cells and animals first?
Where drugs come from
From plants, moulds and chemists.
Traditionally, drugs were extracted from plants and microorganisms. Tap each one.
Most new drugs are now synthesised by chemists in the pharmaceutical industry. However, the starting point may still be a chemical extracted from a plant.
Testing a new drug
Gate by gate.
New drugs are extensively tested for toxicity (is it harmful?), efficacy (does it work?) and dose (how much?). Most candidates fail along the way. Step through the gates.
Preclinical testing is done in a laboratory, first using cells and tissues. Is it toxic? Does it have an effect?
Think again · what is a placebo?
“A placebo is a small dose of the drug.”
Your call
ChooseWhat is a placebo?
Sort
Preclinical or clinical?
Place each test.
Tap a card, then tap the box it belongs in. Tap a placed card to take it back.
Command words in this lesson
- Describe
- The stages in order, and what each checks.
- Explain
- Why a stage is done that way, link by link.
- Suggest
- A reason, using what you know.
Key fact
New drugs are tested for toxicity, efficacy and dose: in cells, tissues and animals first, then in clinical trials, then peer reviewed.
Key note · AQA 4.3.1.9
Drug discovery and development
- Traditionally drugs came from plants and microorganisms: digitalis from foxgloves; aspirin from willow; penicillin, discovered by Fleming, from Penicillium mould.
- Most new drugs are synthesised by chemists; the starting point may still be a plant chemical.
- Drugs are tested for toxicity, efficacy and dose. Preclinical: cells, tissues, live animals.
- Clinical trials: healthy volunteers at very low doses, then patients for the optimum dose. Double-blind with a placebo. Published after peer review.
Photograph this card. Tomorrow, cover it and say each line first.
Previous and next
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Not sure what double-blind means?
The candidate dots are illustrative, not real attrition figures.