Lecture 5 - Does This Drug Really Work? Flashcards
what are clinical trials?
controlled human studies to assess dosage, administration, and safety
- small scale (dozens of subjects)
- tests for tolerable dosing ranges, bioavailability, and excretion
this describes a ___
phase one clinical trial
- intermediate scale (hundreads of subjects)
- testing for efficacy
- monitoring for safety in large numbers
this discribes a ___
phase two clinical trial
- large scale
- randomized
- double-blinded trial
- compared against a placebo or current acepted treatment
this describes a ___
phase three clinical trial
combines data from multiple trials, often after a drug has been approved, to increase confidence in our view of the effectiveness of a drug, and helps guide future policy regarding drug use
systematic reviews/ meta-analysis
forest plots (meta-analysis) provide data on:
- number of trials
- size of each trial
- outcomes of trials
- overall summary of all trials
the ratio of the event rate in treatment vs. control
odds ratio (OR)
what is the ED50?
at this dose, 50% of people have a beneficial effect
what is the LD50?
at this dose, 50% of people have an adverse effect
what is the equation for the therapeutic index?
TI = (LD50) / (ED50)
in patient studies, effect or toxicity is often described using a _____
quantal dose-response curve (see pg. 113 of notes for more)
why is a large therapeutic index good?
it means the drug is tolerated with minimal toxicity and gives a lot of flexibility for dosing
what is the equation for relative risk reduction?
RRR = 1 - ((event rate in treatment group)/(event rate in control group))
why might reporting the RRR be considered misleading?
it does not convey the magnitude of the baseline risk, failing to capture the difference between a reduction in something that is infrequent versus something that is frequent
describes the absolute number of cases that are prevented by taking a drug
absolute risk reduction
