A drug is not considered a new drug only when it is generally recognized as safe and effective (GRASE).

This is a very important concept to grasp, as much hinges on the GRASE determination.

In order to conclude a GRASE determination, a drug must satisfy three criteria:

• First, the particular drug product must have been subjected to adequate and well-controlled clinical investigations that establish the product as safe and effective.
• Second, those investigations must have been published in the scientific literature available to qualified experts.
• Third, experts must generally agree, based on those published studies, that the product is safe and effective for its intended uses. At a minimum, the general acceptance of a product as GRASE must be supported by the same quality and quantity of scientific and/or clinical data necessary to support the approval of a New Drug Application.