The present invention relates to a composition comprising a population of polysaccharide derivatives of a protein, wherein the protein is insulin or an insulin-like protein and the polysaccharide is anionic and comprises between 2 and 125 saccharide units, and wherein the population consists of substantially only N-terminal derivatives of the protein. Typically, the polysaccharide is PSA. The present invention also relates to pharmaceutical compositions comprising the novel compounds, and methods for making the novel compounds.
