The main objective of this study was to prepare colon-specific pellets of
budesonide, using
pectin as film coating. Pellet cores of
budesonide were prepared by extrusion / spheronization technique.
Pectin, in different ratios was combined with
Eudragit RS30D,
Eudragit NE30D or
Surelease to produce film coating. The dissolution profiles of
pectin coated pellets were investigated in pH of 1.2 (2 h), pH of 7.4 (4 h) and pH of 6.8 in the absence as well as presence of rat cecal contents (18 h). Finally the selected formulation was evaluated on
trinitrobenzenesulfonic acid (TNBS) induced
ulcerative colitis in rat model, in comparison with conventional UC treatments. The dissolution profiles of
pectin coated pellets showed that the release of
budesonide in presence of rat cecal content depended on adjuvant
polymer, the ratio of
pectin to
polymer and film thickness. Coated pellets, prepared out of
pectin and
Surelease at a ratio of 1:3 at coating level of 35% (w/w), could increase
budesonide release statistically in presence of rat cecal content, while they released no
drug in pH of 1.2 and 7.4. Animal experiments revealed the therapeutic efficacy of
pectin/
Surelease-coated pellets of
budesonide in alleviating the conditions of TNBS-induced
colitis model as reflected by
weight gain, as well as improvement of clinical, macroscopic and microscopic parameters of induced
colitis. This confirmed the ability of the optimized formulation for targeted
drug delivery of
budesonide to colon.