Clinical trials

Question 1

What is a phase 0 or pre-clinical trial phase?

Answer 1

Testing of a drug on non-human subjects to determine if the drug is active and pharmacokinetics

Question 2

What is a phase 1 trial?

Answer 2

Testing of a drug on healthy volunteers at low but escalating doses. Determines dose

Question 3

What is a phase 2 trial?

Answer 3

Testing of a drug on a population of patients with the disease. Determines safety

Question 4

What is a phase 3 trial?

Answer 4

Testing of a drug compared with placebo or another drug, on patients who have the disease. Determines effectiveness compared with placebo or other therapies

Question 5

What is a phase 4 trial?

Answer 5

Post marketing study, for ongoing surviellance to monitor for unseen toxicites previously

Question 6

How many participants are there usually in a phase 1 trial?

Answer 6

Small numbers, 20-100 healthy volunteers

Question 7

How many participants are usually in a phase 2 trial?

Answer 7

Around 100-300 patients with the disease

Question 8

How many participants are there in a phase 3 trial?

Answer 8

Large numbers of patients, 1000-2000, often multi-centre RCTs