This invention describes a novel family of polysaccharide prodrugs with
enhanced colonic delivery advantage. The prodrugs are synthesized by
chemically linking a parent compound with a specially selected
polysaccharide (M.W. 105-107 Da) containing galactose residues. Its
characteristics are that it is synthesized by chemically linking
polysaccharides with the parent compound through different bridge links
for targeted colonic delivery; that the polysaccharides contain galactose
residues. Because of this, the polysaccharide component can protect the
parent compound from absorption (or metabolism) in the upper
gastrointestinal tract and deliver a high concentration of the bound
compound to the colonic area. Upon reaching the colon, the active
component of the parent drug will be released locally from the
polysaccharide via enzymatic hydrolysis, allowing it to act locally for
colonic disease such as inflammation or infection and/or taking advantage
of the favorable microenvironment in the colon for steady and stable
colonic drug absorption.