Colonic Drug Targeting Approaches for Treatment of Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is an idiopathic, relapsing disease involving chronic inflammation of the digestive tract, either in part or entire. IBD primarily includes Crohn’s disease (CD) and ulcerative colitis (UC) with a high prevalence rate in the industrialized world, with North America noting the highest frequency of people suffering with CD [1]. Incidence of IBD is from 31 to 71 per100,000 people for CD and 18-31 per 100,000 for UC and is increasing at an alarming rate. Although, adults are the most frequently diagnosed ones, reports show a significant population of paediatric is also being diagnosed with IBD [2].

CD results in inflammation throughout the digestive tract lining and this inflammation often spreads deeper into tissues. Moreover, UC results in chronic inflammation, ulcers and sores in the innermost lining of large intestine especially in colon and rectum [3]. The situation could increase the complications with diarrhoea, fatigue, pain, and weight loss and at times usher to life- threatening conditions.

The exact etiology of IBD remains unknown [4]. Nevertheless, genetic predisposition, immune malfunction, and environmental factors increase the risk of inflammation [5,6]. There is no cure for IBD. Therapeutic goals are aimed in improving the patient’s quality of life by maintaining remission, predicting, preventing and treating complications, restoring nutritional deficits, providing appropriate psychosocial support, and modifying the course in those individuals with aggressive disease [7]. Treatment of IBD majorly includes anti-inflammatory drugs, antibiotics, biologic agents, immunosuppressants or those for symptomatic relief only [7]. Commonly, two different paradigms for IBD treatment are followed. The “step-up” paradigm starts initially with milder drugs i.e. aminosalicylates, immunomodulators (corticosteroids) followed by surgery or biologics while “step-down,” follows the vice versa [8].