Advances in colonic drug delivery

Area of Science:

• Gastroenterology
• Pharmaceutics
• Drug Delivery Systems

Background:

• Targeting drug delivery to the colon is crucial for treating local gastrointestinal disorders like inflammatory bowel disease and colorectal cancer.
• The colon is also recognized as a significant route for systemic drug absorption.
• Current challenges include limitations in specificity, manufacturing complexity, and cost of existing and developmental colonic drug delivery systems.

Purpose of the Study:

• To review and evaluate various strategies for colonic drug targeting.
• To identify the most promising approaches for effective and practical colonic drug delivery.
• To highlight the advantages of microflora-responsive systems.

Main Methods:

• Review of existing literature on colonic drug delivery systems.
• Analysis of strategies based on gastrointestinal tract features (pH, transit time, pressure, microflora).
• Evaluation of commercialized and developmental systems, including coated systems, prodrugs, and polysaccharide-based systems.

Main Results:

• Commercialized systems like pH-dependent coatings and bacterial-activated prodrugs have limitations.
• Many developmental systems face challenges in manufacturing, cost, and site-specificity.
• Universal polysaccharide systems, leveraging the colon's abundant microflora, are identified as highly promising.

Conclusions:

• Exploiting the colon's unique microflora offers a practical and effective approach for targeted drug delivery.
• Universal polysaccharide systems represent a favorable strategy due to their practicality and reliance on colonic bacteria.
• Further development in polysaccharide-based systems could overcome current limitations in colonic drug targeting.