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Flashcards in Clinical trial design Deck (12)

Discuss the uses of a clinical study. 

• Does it work?
• What dose is therapeutic?
• What dose is toxic?
• Is it safe?
• Is it necessary? Compare to industry standard

Tests efficacy and safety of a potential new drug


Discuss the basic considerations involved in trial design. 

What controls are needed
Define clinical endpoints
Number of subjects required
Choice of subjects e.g. age, race, gender
Safety endpoints
Exclusion and selection criteria


Discuss the importance of statistical power

Tells if there is a significant effect, not just by chance
p<0.05 usually taken as significance, P<0.001 very significant


Give a famous example of a cohort study

Tuskegee Study of Untreated Syphilis (1932 to 1972)


What are the different stages in drug development?

• Drug discovery – discovery of new candidate medications
• Phase I volunteer studies - clinical pharmacology in normal volunteers generating pharmacokinetic, metabolic and pharmacodynamic data.
• Phase II development - Clinical investigation to confirm kinetics and dynamics in patients with ailment
• Phase III clinical development - Formal therapeutic trials where efficacy will be established and evidence of safety obtained
• Phase IV surveillance - Post-marketing surveillance to produce evidence of long term safety


What is a double bind clinical trial?

Double blind: neither patient or doctor knows what drug the patient is on


Whats a single blind clinical trial?

Single blind: patient doesn’t know what they’re on


Whats a prospective clinical trial?

– Prospective: watches for outcomes, such as the development of a disease, during the study and relates it to other factors such as a suspected risk or protection factor.


Whats a retrospective clinical trial?

– Retrospective: data is collected from case records after treatment is given


Whats a cross over clinical trial?

– Cross-over design: patients take both treatments, new trial drug and previously licensed drug, one after the other following a wash out period


What are some disadvantages of randomised control clinical trials?

• Generalizable Results?
o Subjects may not represent general patient population
o Tend to be better at complying
• Recruitment
o Twice as many new patients needed for the study
• Acceptability of Randomization Process
o Some physicians will refuse (PFO closure)
o Some patients will refuse (want treatment)
• Administrative complexity (randomisation methods)


Whats the difference between superiority and non-superiority trials?

Superiority Design: Shows that new treatment:
o Is better than the control or standard (maybe a placebo)

Non-inferiority: Show that the new treatment:
o Is not worse that the standard by more than some margin
o Would have beaten placebo if it had been included (regulatory