The invention relates to cyclopeptides, the method of their preparation and their utilization as inhibitors or activators of angiogenesis.These cyclopeptides comprisecontain the following peptide sequence:-Arg-Ile-Lys-Pro-His-Gln-Gly- (SEQ ID NO: 1).They can be used in systems for inhibition of angiogenesis that comprisesinclude a support (1), to which the cyclopeptide is affixed by means ofcoupled via an organic spacer arm (3) that may be provided with a moiety (4) capable of being splicedcleaved by an enzyme system.