Peptides that have antiangiogen activity.

A compound of formula (I) or a pharmaceutically acceptable salt thereof wherein Xaa1 is selected from the group consisting of: acetyl, and 6-methylnicotinyl; Xaa2 is sarcosyl; Xaa3 is glycyl; Xaa4 is selected from the group consisting of aloisoleucyl allyl glycyl or, 2-aminobutyryl, (1R, 4S) -1-aminocyclopent-2-ene-4-carbonyl, 3- (5-bromothien-2-yl) alanyl, 3- ( 3-chlorophenyl) alanyl, 3- (4-chlorophenyl) alanyl, 3- (3-cyanophenyl) alanyl, cysteinyl (S-ethyl), cysteinyl (S-methyl), 2,3-diaminopropionyl; 2,4-diaminobutanoyl, 3- (3, 4-dimethoxyphenyl) alanyl, 3- (3- fluorophenyl) alanyl or, 3- (4-fluorophenyl) alanyl, homophenylalanyl, homoseryl, lysyl (N-epsilon-acetyl), methionyl (sulfon a), methionyl (sulfoxide), 3- (4-methylphenyl) alanyl, 3- (naphth-1-yl) alanyl, 3- (naphth-2-yl) alanyl, ornithyl, phenylglynyl, 3- (3- pyridyl) alanyl, seryl (O-benzyl), styrylalanyl, 1, 2, 3, 4-tetrahydroisoquinolin-3-carbonyl, 3- (thiazolyl) alanyl, 3- (thien-2-yl) alanyl, and D-3- (thien-2-yl) alanyl; Xaa5 is selected from the group consisting of isoleucil, D-isoleucil, and D-leucil; Xaa6 is selected from the group consisting of seryl, and threonyl; Xaa7 is selected from the group consisting of glutaminyl, norvalyl, and seryl; Xaa8 is isoleucil; Xaa9 is arginyl; Xaa10 is prolific; and Xaa11 is selected from the group consisting of D-alanylamide, and NH-ethyl.