The present invention relates to novel salt forms of 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine, processes for making these novel salts, and pharmaceutical compositions comprising such novel salts. The invention also relates to the use of these novel salts in the treatment of type 2 diabetes.