Atopic dermatitis (AD), also referred to eczema, is a common inflammatory skin disease that usually presents during infancy or childhood but affects patients of all ages. It is a pruritic, chronic/relapsing condition that may significantly impact the patients’ quality of life and can be associated with other atopic comorbidities including asthma and rhinoconjunctivitis. Inflammation in AD is mostly sustained by type 2 inflammation. Most patients are satisfactorily managed with a combination of emollients, avoidance of triggering factors, topical glucocorticoids, and/or topical calcineurin inhibitors. However, a proportion of patients with moderate or severe AD might require phototherapy or systemic immunosuppressants, which are limited in time due to possible safety concerns and progressive efficacy loss. In recent years, the availability of T helper 2 (Th2)-blocking agents dupilumab and tralokinumab has revolutionized the long-term treatment of moderate-to-severe AD. Here are discussed recent advances in the clinical development of biologic treatments for AD. The clinical implementation of these novel drugs has the potential not only to greatly improve the quality of life of patients with this chronic and disabling condition but also to clarify the biological processes underlying AD, in turn enabling further development of more effective, safer treatments. This research paper aims to provide an overview of biological therapies currently in use and under investigation in the setting of AD.

Allergen-specific immunotherapy (AIT) is a proven efficacy treatment for allergic rhinitis (AR), asthma, and Hymenoptera venom allergy, but its use in food allergy (FA) is still under investigation. Because some efficacy and safety concerns still remain, biologic drugs, including omalizumab and dupilumab, have been studied as an adjunctive therapy to AIT for these conditions. In this article, the evidence supporting the use of monoclonal antibodies (mAbs) as an add-on therapy to AIT for FA, AR, asthma, and Hymenoptera venom allergy has been reviewed. The review will delve into the mechanisms of action of different mAbs, their efficacy, and how they can be integrated into personalized medicine approaches to treat allergic diseases. Furthermore, future research areas will be considered. Evidence suggests that omalizumab in combination with AIT may be a beneficial option for respiratory allergies or food desensitisation, especially during the escalation or build-up phase, when adverse events are more frequent. Currently, there is a small number of well-structured clinical trials in Hymenoptera venom allergy, and the available data consist mainly of single-case reports that provide information of limited value. Dupilumab has been studied as adjunctive therapy in patients with respiratory and FAs. Clinical trials are ongoing to evaluate the efficacy of dupilumab as monotherapy or as an adjunct to oral immunotherapy (OIT) in peanut allergy. Other studies are investigating the use of dupilumab in patients with multiple FAs and as an adjunct to milk OIT. Overall, mAbs have the potential to improve outcomes in various allergic conditions when used as an add-on to AIT, especially during the build-up phase. Further research is needed to fully understand their optimal dosing and duration of treatment, as well as to identify which patients may benefit the most from these therapies.

The advent of biological drugs has opened up new therapeutic possibilities in the field of eosinophilic gastro-intestinal diseases (EGIDs). EGIDs are chronic inflammatory diseases of the gastrointestinal tract unrelated to drugs or infections, and eosinophilic esophagitis (EoE) is the most frequent form. EGIDs are complex disorders, which pathogenesis is still partially unknown. The diagnosis of EGIDs relies on the combination of different data, such as clinical manifestations, laboratory tests, endoscopic, and histological data. The gold standard at present is the histological examination obtained from biopsies under endoscopic guidance, but the diagnostic criteria for each disorder are still not fully defined, and few clinical scores are validated, for all these reasons, conducting clinical trials on EGIDs is challenging. The dietary approach remains currently a first-line treatment, despite its efficacy being influenced by patients’ compliance. Exclusion diets, nevertheless, involve potential nutritional deficiencies. Two of the pivotal pharmacological therapies for the treatment of EGIDs are proton pump inhibitors (PPIs), especially for EoE, and systemic or topical steroids. Long-term corticosteroid therapies are, however, associated with even severe side effects, so steroid-sparing therapies are needed to achieve the same results, in the last years monoclonal antibodies have been studied. To date, dupilumab is the only approved biological drug for EoE therapy, but many others are currently being tested in clinical trials also for the other forms of EGIDs. This work presents a complete review of the role of biological drugs in EGIDs to date, systematically structured by pathology.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a multiorganic syndrome that affects the cardiovascular, neurologic, renal, and gastrointestinal systems with an incidence ranging from 0 case to 67 cases per one million person-years, and its pathophysiology remains unknown. It is believed that genetic factors, the environment, and changes in immune system function contribute to the development of EGPA, overlapping the immune mechanisms of vasculitides and the pathologic mechanisms in eosinophilic syndromes. This disease is commonly divided into two phenotypes depending on the presence of antineutrophil cytoplasmic antibodies (ANCA). ANCA-positive patients usually have more vasculitic manifestations like peripheral neuropathy, purpura, renal involvement, and biopsy-proven vasculitis. The keystone of EGPA therapy is systemic corticosteroids (CS) as monotherapy or in combination with other immunosuppressive treatments, and recently the efficacy of eosinophil-targeted biotherapy, anti-interleukin-5 (IL-5), has been shown to be efficacious in EGPA. Although this phenotype/phase distinction has not yet had an impact on the current treatment strategies, emerging targeted biotherapies under evaluation could lead to a phenotype-based approach and personalised treatment regimens for EGPA patients. The present review describes the new therapeutical approaches with biological drugs for EGPA.