Phase III Trials: Phase III trials are used to prove the efficacy and safety of a drug over the long term and verify Phase II results. These trials are usually double-blinded and placebo-controlled and involve upwards of 1000 patient volunteers. Larger-scale trials are required to see if previously unseen side effects or changes in the drug's efficacy profile appear when testing is done on a sizeable population. Upon completion of this phase, and if the data warrants, a company will file a New Drug Application (NDA) with the FDA.

Dose Optimization: involves a balance between acceptable safety/tolerance and the desired pharmacologic effect.