Clinical Trial Design

Question 1

Why are clinical trials important?

Answer 1

• provide evidence
• to test efficacy compared to placebo and other drugs
• to test safety

Question 2

Why are clinical trials conducted?

Answer 2

What works in theory might not be best practice

Question 3

What is the cost of a clinical trial from chemical structure to licensed drug?

Answer 3

• more than 10 years

- £100 million

Question 4

What is involved in pre clinical development?

Answer 4

• animal pharmacology (dose, adverse effects)
• animal toxicology (teratogenicity, fertility, mutagenicity)
• tissue culture

Question 5

What does phase 1 in clinical development involve?

Answer 5

-Volunteer studies= clinical pharmacology in normal volunteers generating pharmacokinetic, metabolic and pharmacodynamics data

Question 6

What does phase 2 in clinical development involve?

Answer 6

• clinical investigations to confirm kinetics and dynamics in patients
• provides some evidence of efficacy and identifies a likely dosage range

Question 7

What does phase 3 in clinical development involve?

Answer 7

• formal therapeutic trials where efficacy will be established and evidence of safety obtained
• at completion, all data is submitted as an application to the regulatory authority for a license to sell the drug

Question 8

What does phase 4 of clinical development involve?

Answer 8

-post-marketing surveillance to produce evidence of long term safety

Question 9

What does a pilot study do?

Answer 9

Tests study design

Question 10

What kind of trials are there?

Answer 10

• double blind
• single blind
• prospective
• retrospective
• randomised
• placebo controlled
• comparison with other therapy
• cross over

Question 11

What are the disadvantages of randomised control trials?

Answer 11

• Subjects may not represent general patient population
• twice as many new patients needed for the study
• some physicians will refuse (PFO closure)
• some patients will refuse (want treatment)
• complexity of randomisation methods

Question 12

Superiority vs Non-inferiority trials

Answer 12

• superiority design show that the new treatment is better than the control or standard
• non-inferiority show that the new treatments is not worse that the standard by more than a margin or would have beaten placebo if a placebo arm had been included

Question 13

What can act as end points to a trial?

Answer 13

• death
• no of hospital admissions
• lowering of bp
• comparison of pain or mood

Question 14

What does p<0.05 mean?

Answer 14

Usually represents significant results