A 779 is primarily used in research settings as a selective antagonist for the angiotensin II receptor type 2 (AT2). It helps scientists investigate the physiological and pathological roles of the AT2 receptor, particularly in cardiovascular function, inflammation, and tissue injury. Due to its specificity, A 779 is valuable in studies exploring blood pressure regulation, renal function, and neuroprotection. It is also employed to differentiate AT2-mediated effects from those acting through the AT1 receptor in experimental models. Its application remains confined to laboratory and preclinical research, with no current use in clinical therapy.