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What is Pharmacoepidemiology is this phase of clinical trial: and explain in detail?
(Ref: Goodman & Gillman 13th ed. P 6)Clinical Trials and its characteristicsPhase I first in humanPhase II first in patientPhase III multisite trialPhase IV post marketing surveillance10-100 participants50-500 participantsA few hundred to a few thousand participantsMany thousands of participantsUsually healthy volunteers; occasionally patients with advanced or rare diseasePatient-subjects receiving experimental drugPatient-subjects receiving experimental drugPatients in treatment with approved drugOpen labelRandomized and controlled (can be placebo controlled); may be blindedRandomized and controlled (can be placebo controlled) or uncontrolled; may be blindedOpen labelSafety and tolerabilityEfficacy and dose rangingConfirm efficacy in larger populationAdverse events, compliance, drug-drug interactions1-2 years2-3 years3-5 yearsNo fixed durationUS $10 millionUS $20 millionUS $50-100 million-Success rate: 50%Success rate: 30%Success rate: 25%-50%-Maximum drug failure occur in this phase: Phase IIMost important phase of clinical trial: Phase IIIA new drug is launched in market after phase IIIPhase 0 trial is microdosing study, done on normal healthy volunteers. To study the PK/PD of drug by radio labelling and administering.Phase 5 clinical trial is Pharamcoepidemiology.Phase 0 and 1 done on normal healthy volunteers.