FDA: evidentiary standards for drug development and approval.

The United States Food and Drug Administration is charged with approving drug treatments that have been shown to be safe and effective. Relevant statutes and regulations provide a legal framework for establishing safety and effectiveness that is sufficiently flexible to ensure that appropriate scientific data are collected for specific treatments targeted to particular diseases. Nonetheless, all clinical trials proposed to establish effectiveness must incorporate common elements in order for the appropriate legal and scientific standards of drug approval to be met. This article will discuss the relevant laws and regulations pertaining to the current effectiveness standard and will discuss the most important clinical trial design elements currently considered acceptable for applications for treatments of neurologic and psychiatric illness.