Careful evaluation of the dose response relationship and pharmacokinetics
Phase I
Evaluation of a drug in a moderate number of patients
Phase 2
Placebo or positive control drug is included
Phase 2
Comparing drugs to older therapies
Phase 3
Post marketing surveillance
Phase 4
Doae efficacy
Phase 2
Normal volunteers, pharmacokinetics and dose sensitve acute effects
Phase I
Drug is tested on a large number if patients, toxicities are observed
III
Idiosyncratic reactiona are monitored
Phase 4
Standard in vitro test for mutagenecity
Ames test