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What is Efficacy of new drug is confirmed in which phase? and explain in detail?
Clinical trials are divided into 4 phases: Phase I Done in healthy people - To know:- Max. tolerable dose (MTD) > Dosing >PK >Safety Phase II Done in 20-200 patients- To determine efficacy (first time) and safety Phase III Done in large no of patient upto 5000 (Multi centric)- to confirm efficacy and safety Phase IV Post marketing study - Rare/Long term side effects