(ak-SEH-leh-ray-ted uh-PROO-vul) An official process that allows a new drug to be approved by the U.S. Food and Drug Administration (FDA) before it has gone through all of the required levels of testing in humans. It is only used for drugs that treat serious or life-threatening diseases for which other treatments may not be available or may no longer be effective. A drug may be approved through the accelerated approval process if it has shown certain signs in clinical trials that it might be beneficial for patients, such as a shrinking tumor. Further testing of the drug is required after it has received accelerated approval and is on the market to confirm that it really works. Accelerated approval is one way that patients can receive promising new drugs when other treatment options may not exist.