Biologic agents and small molecules – mechanism of action

Inflammatory bowel diseases are a group of chronic, relapsing disorders of the gastrointestinal tract. The initially limited therapy options were significantly expanded with the advent of biologics and small molecules. Biologics and small molecules can be divided into four categories based on their immunologic targets – anti-tumor necrosis factor, anti-interleukin, anti-integrin, and janus kinase pathway inhibitor. Each class of medication functions through a particular mechanism of action that dictates its indications for use, rate of efficacy, and safety profile.