Selectivity sequential hypothesis

The paradigm in drug development is sequentially divided into several phases starting with preclinical assessment. After selection of a drug candidate based on preclinical studies, clinical Phase 1 studies are initiated to characterize the safety, tolerability, biomarker, and pharmacokinetic profiles of the candidate, typically in healthy subjects. Phase 2 studies test the drug efficacy hypothesis in patients and explore dose range, and Phase 3 studies aim to demonstrate efficacy in the intended patient population in a statistically robust manner. 

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