Clinical Trials Flashcards
Why are clinical trials important?
They provide evidence - practice is evidence based
What is defined as pre-clinical development?
Investigating animal pharmacology
Investigating animal toxicology
Tissue culture
What is phase 1 of clinical development?
Clinical pharmacology in normal ‘healthy’ volunteers generating pharmacokinetic, metabolic and pharmacodynamic data.
100 subjects
Which drugs are not usually seen in phase 1 clinical trials?
Certain cytotoxic drugs - that cause harm to the individual
What is phase 2 of a clinical trial?
Involves up to 500 patients
Provides some evidence of efficacy and identifies a likely dosage range
Confirms kinetics and dynamics
What is phase 3 of a clinical trial?
Efficacy is established and evidence of safety is obtained
It determines if the drug works for the condition we are testing
All data collected and used to request a license to sell the drug
1000-3000 patients
What is phase 4 of clinical development of a drug?
Post marketing surveillance to produce evidence of long term safety
What is the purpose of a pilot study?
To test study design
What are the different methods of trials?
Double blind
Single blind
Prospective
Retrospective
What are the stages of a prospective clinical trial?
Design the study, recruit, then follow up
What is a retrospective clinical trial?
When data is collected from case records after treatment is given
What is a cross over study?
When patients receive both methods of treatment, one after the other with a cross over stage in the middle called a “wash out period” - removes all the old drug
What is the difference between a superiority VS a Non-inferiority trial?
Superiority - Shows that a new treatment is better then control (standard or placebo)
Non-inferiority - shows that the new treatment is not worse than the standard by much
Shows that the new treatment would have beaten a placebo arm
Who might you exclude from a clinical trial?
Pregnant women Children Seriously ill Elderly Patients at risk of side effects
What is the measurement of statistical significance?
Statistical significance involves measuring the probability that the results you collected were due to randomness - as opposed to the different factor different subjects were exposed to.
The process involves mixing the data from both sets randomly to create a new range of mean values. This process is repeated many times, from there you can determine how likely the chances are of experiencing a similar difference in measurements between the randomised mean values and the actual difference obtained.
If there was one very large sample measurement that greatly boosted the mean value for that set of data, then this would account for the data set being very high, regardless of wether or not the ‘factor’ had affected the rest of the group. By creating a new set of mean values, you can see that in all cases there will be a significant difference in data sets, so the probability of the data coming from randomness is very high.