Clinical Trials Flashcards
What is required for clinical trials?
Evidence
What are the two reasons drugs need to be tested?
Efficiency
Safety
What is the point of pilot studies?
To test study design.
What are the 4 types of trials?
Double blind
Single blind
Prospective
Retrospective
What does a placebo controlled study allow the comparison of?
Outcome in the groups of active drug and placebo drug.
What does a comparison with other therapy study allow the comparison of?
End points (is A better than B)
What is the problem with observational studies?
Correlation vs. Causation
How long can it take to get a chemical structure to a licensed drug?
10 years
What are the 3 types of pre clinical development tests?
Animal pharmacology (dose, adverse effects) Animal toxicology (fertility issues, tumours etc) Tissue culture
What is phase 1 of clinical development?
Volunteer studies
What type of drugs bypass phase 1?
Cytotoxics
What is phase 2 of clinical development?
Investigation with 500 patients to confirm kinetics and dynamics.
What does phase 2 provide?
Evidence of efficacy and identifies a dosage range.
What is phase 3 of clinical development?
Formal trials where efficacy will be established and safety confirmed. 1000-3000 patients.
What is phase 4 of clinical development?
Post-marketing surveillance to produce evidence of long term safety.
What is a double blind study?
When neither the patient nor the doctor knows what drug the patient is getting.
What is a single blind study?
When the patient doesn’t know what is happening but the doctor does. Not as good as double blind.
What is a prospective study?
Design the study, recruit the patients and give the drugs.
What is a retrospective study?
Looking at people on a certain drug and another drug, but more biased as you aren’t doing the work yourself.
What can cross over designs decrease?
Number of people in the study
What is a cross over design?
When they try both drugs but with a break in between.
What are the disadvantages of randomised control clinical trial?
May not represent general patient population (would take drugs correctly which doesn’t always happen)
Twice as many patients needed for the study
Some physicians refuse closure and patients want treatment, not placebo.
Complexity
What are 2 commonly used phase 3 designs?
Parallel
Cross voer
What does a superiority design show?
New treatment is better than control.
What does a non-inferiority study show?
New treatment is not worse than standard by a margin, would have beaten placebo.
When designing a study, what should endpoints be?
As simple as possible
What 4 things are required when designing a study?
Hypothesis
Endpoints
Number of subjects
Safety endpoints
What is usually taken as the statistical test?
p<0.05
What does a statistical test prove?
If there is a significance in results.
What are the 2 interpretations of insignificant findings?
No difference (may be bad study) Two treatments are clinically equivalent.
