Once a new compound has been discovered in a laboratory, a pharmaceutical company conducts studies to show biological activity of the compound against the targeted disease, and the compound is evaluated for safety. After preclinical testing, the pharmaceutical company files an IND with the FDA to begin to test the medication on people. The tests study a medication's safety profile, including the safe dosage range. The studies also determine how a medication is absorbed, distributed, metabolized, and excreted, as well as the duration of its action. This phase usually involves 1,000 to 3,000 patients in clinics and hospitals.
Physicians monitor patients closely to confirm efficacy and identify adverse effects.
The NDAs typically run 100,000 pages or more. Once the FDA approves an NDA, the new medicine becomes available for physicians to prescribe. A company must continue to submit periodic reports to the FDA, including any cases of adverse reactions and appropriate quality-control records. Potential medications in this development pipeline are first given an assigned series of numbers and letters. With hope, and some patience, many of these medications may become available in the US within the next few years - some sooner than others.