Table 1 Steps in Drug Development

Discovery and Concept Development

   • Target Identification and Validation

   • Assay Development and Screening

   • Lead Molecule Discovery

   • Lead Molecule Optimization

   • Pharmacodynamics and Toxicology

Proof of Concept/IND

   • Clinical Phase I: PK/PD, ADME, abuse liability

   • Phase II Proof of Concept

Product Development

   • Phase III Registration

   • NDA Approval

   • Phase IV Post Marketing