Anti-Interleukin Biologics for the treatment of the Atopic March Diseases

The atopic march refers to the natural history of allergic disorders as they develop from infancy to childhood. Classically, the atopic march begins with atopic dermatitis (AD), followed by food allergy, advancing to asthma, allergic rhinitis (AR), and finally to the fifth member eosinophilic esophagitis. The pathogenesis of the atopic march is complex, and involves genetic, immunological, and environmental factors. T helper type 2 (Th2) lymphocytes, and epithelial cells play a key role in the pathogenesis of the diseases in the atopic march. Th2 cells secrete cytokines, such as interleukin-5 (IL-5), IL-4, and IL-13, whereas, epithelial cell injury release alarmin cytokines, including IL-25, IL-33, and thymic stromal lymphopoietin (TSLP). Th2 cells and alarmin cytokines play an important role in the development of eczematous skin lesions, airway inflammation and remodeling, and oesophageal mucosal inflammation. Treatment of eosinophilic asthma and associated comorbid disorders is challenging, and requires a precision targeted approach with biologics. Dupilumab is a fully humanized IgG4 monoclonal antibody to the IL-4Rα, which mediates signaling to both IL-4 and IL-13, and blocks their immunopathological effects. Dupilumab is the only biologic that has been approved for the treatment of eosinophilic asthma, AD, and eosinophilic esophagitis. In patients with eosinophilic asthma treatment with dupilumab has been shown to improve asthma control, reduce exacerbations, and improve lung function. In patients with atopic dermatitis dupilumab has been demonstrated to improve the Eczema Area Severity Index (EASI) score, Investigator’s Global Assessment (IGA) response, SCORing Atopic Dermatitis (SCORAD) score, and the Peak Pruritus Numerical Rating (PNR) scale. Lebrikizumab and Tralokinumab (anti-IL-13) failed to show the expected results for the treatment of asthma, astoundingly, in several clinical trials they have been shown to significantly improvement EASI score, IGA response, SCORAD score, PNR scale, sleep architecture, and Dermatology Life Quality Index (DLQI). They have been granted First Tract Designation, and European Commission regulatory approval, respectively. Tezepelumab (anti-TSLP) is approved for the treatment of eosinophilic asthma, and has been shown to significantly reduce exacerbations, and improve asthma control, lung function, and HLQoL. However, tezepelumab did not meet the endpoints in phase II for the treatment of AD. Keywords: Atopic March; Atopic Dermatitis; Eosinophilic Asthma; Interleukin; Dupilumab; Tralokinumab