MENLO PARK, CA--(MARKET WIRE)--Jul 25, 2007 -- Corcept Therapeutics (NasdaqCM:CORT - News) and Xceleron today announced an agreement for a human microdosing study of one of Corcept's new chemical entities, a selective GR-II antagonist, utilizing Xceleron's Accelerator Mass Spectrometry (AMS) technology.