Abstract: Disintegrin variants that bind specifically to one or more of ?5?1 and ?v integrins, such as ?v?1, ?v?3, ?v?5, ?v?6 and ?v?8, but with reduced binding activity to ?IIb?3, are described. Also described are uses of the disintegrin variants for the treatment or prevention of a disease associated with an ?v integrin or an ?5?1 integrin.