Dupilumab: Mechanism, Indications, and Monitoring

Overview / Definition Dupilumab is a fully human monoclonal antibody that inhibits interleukin-4 (IL-4) and interleukin-13 (IL-13) signaling, which are crucial mediators in the pathogenesis of various allergic and inflammatory diseases. It is primarily indicated for moderate to severe atopic dermatitis, asthma, and chronic rhinosinusitis with nasal polyps. Epidemiology Atopic dermatitis (AD) affects approximately 10-20% of children and 1-3% of adults worldwide. Dupilumab has emerged as a key therapeutic option for those with moderate to severe forms of the disease, particularly in patients who have not responded adequately to topical therapies. The prevalence of asthma and chronic rhinosinusitis is also significant, with asthma affecting about 8% of the population and chronic rhinosinusitis affecting approximately 12%. Pathophysiology / Mechanism The inflammatory process in atopic dermatitis is characterized by a Th2-skewed immune response, where IL-4 and IL-13 play pivotal roles in promoting inflammation, barrier dysfunction, and pruritus. Dupilumab binds to the IL-4 receptor alpha subunit, inhibiting both IL-4 and IL-13 signaling pathways: IL-4 promotes IgE production and eosinophilia. IL-13 is involved in epithelial cell activation and mucin production. By blocking these pathways, dupilumab reduces inflammation, improves skin barrier function, and alleviates symptoms in patients with atopic dermatitis and other related conditions. Clinical Presentation Patients treated with dupilumab typically present with: Improved skin hydration and reduced scaling in atopic dermatitis. Decreased frequency and severity of asthma attacks. Reduction in nasal obstruction and sinus symptoms in chronic rhinosinusitis. Common symptoms in atopic dermatitis include severe itching, redness, and lesions that can become infected. In asthma, patients may experience wheezing, shortness of breath, and chest tightness, while chronic rhinosinusitis is characterized by nasal congestion, facial