Abstract: The present invention is directed to a method of identifying an inhibitor or enhancer of &agr;v&bgr;3 activity by contacting superactivated &agr;v&bgr;3 integrin with one or more molecules; and assaying an &agr;v&bgr;3 integrin activity, where reduced &agr;v&bgr;3 activity identifies an inhibitor of &agr;v&bgr;3 activity and where enhanced &agr;v&bgr;3 activity identifies an enhancer of &agr;v&bgr;3 activity. In a preferred embodiment, a cell, such as a MCF-7 breast carcinoma cell, is transfected with a nucleic acid molecule encoding a superactivated &bgr;3 variant, which can have, for example, substantially the amino acid sequence of SEQ ID NO:6 shown in FIG. 3.