Scientists have discovered a new drug to treat a bacterial infection.
In a later clinical trial, patients with the infection were given either the new drug or a placebo.
The Table shows the results of this trial.
Table
| Treatment | Number of patients | Number of patients who recovered in one week |
|---|---|---|
| new drug | 300 | 255 |
| placebo | 300 | 120 |
Before the drug is tested on humans, it goes through preclinical testing.
Describe what happens in preclinical testing.
In the first stage of clinical testing, the drug is given at a low dose to a small number of healthy volunteers.
Explain why.
Use the Table to calculate the percentage of patients who recovered in one week in each group.
Explain why some patients were given a placebo.
45 exam-style questions on Edexcel GCSE Biology 5.3 Immune system and medicines, covering 5.3.1 The specific immune system, 5.3.2 Response to immunisation, 5.3.3 Advantages and disadvantages of immunisation, 5.3.4 Antibiotics and bacterial infections, 5.3.5 Aseptic techniques in culturing, 5.3.6 Cross-sectional areas of cultures, 5.3.7 Stages of developing new medicines, and 5.3.8 Production of monoclonal antibodies. Each one has a worked solution and a mark scheme showing where the marks go.