Insulinotropic peptides glucagon, compositions and methods.

A GLP-1 comprising a valine substitution for alanine at position 8 and further comprising one or more additions or deletions of amino acids, with the proviso that the analog GLG-1 polypeptide not found in the formula: wherein: R1 is selected from L-histidine, D-histidine, desamino-histidine, 2-amino-histidine, hydroxy-histidine-â, homohistidine, alpha-fluoromethyl-histidine, and alpha-methyl- histidine; X is selected from Val, Thr, Ile, and alpha-methyl- Ala; Y is selected from Glu, Gln, Ala, Thr, Ser, and Gly; Z is selected from Glu, Gln, Ala, Thr, Ser, and Gly; R2 is selected from NH2, and Gly-OH; and provided further that the GLP-1 demonstrate insulinotropic activity.