Colon Delivery of Budesonide Using Solid Dispersion in Dextran for the Treatment and Secondary Prevention of Ulcerative Colitis in Rat

Abstract

Objectives: Ulcerative colitis is characterized by local inflammation.
Targeting drugs directly to the site of injury has the benefit
of lower adverse effects and more effective therapy. The aim of
this study was colon targeted delivery of budesonide to deliver the
major part of the drug to the colon.
Methods: Matrix tablets of budesonide from solid dispersion of
drug with dextran were prepared using different drug to polymer
ratios and three molecular weights of dextran. The physical
evaluation and drug release behavior were studied. In vivo efficacy
of the selected formulation against acetic acid induced colitis in
rats was evaluated and compared to the control (untreated) and
references (mesalazine and budesonide suspensions) groups.
Results: The results showed that solid dispersion of budesonide
with dextran in the ratio of 1:7 using molecular weight (MW) of
10,000 dextran (SDT710) released 25% of the drug in the first 6
hours and 100% in caecal and colonic contents. It could target the
drug to colon with improvement in some of the inflammatory
signs of induced ulcerative colitis in rat. Treatment with SDT710
could improve not only the percent of involvement also macroscopic
damage parameters. The macroscopic parameters included
weight/length ratio of the colon, ulcer area, damage score, and
ulcer index reduced in comparison to the control group and conventional
suspension of budesonide; however, only weight/length
ratio was significant.
Conclusions: In the experimental model studied, the new colonic
delivery system significantly improved the efficacy of budesonide
in the weight/length ratio of the colon in induced colitis in rats.
Keywords: Budesonide; Solid dispersion; Dextran; Ulcerative colitis;
Colon delivery.