Successful treatment with benralizumab in a patient with eosinophilic granulomatosis with polyangiitis refractory to mepolizumab

Eosinophilic granulomatosis with polyangiitis (EGPA) is characterized by necrotizing eosinophilic granulomatous inflammation that frequently involves the respiratory tract (90% of cases). Asthma in EGPA is systematically severe and often refractory to common treatment, it is corticosteroid resistant and can often anticipate the onset of systemic vasculitis by many years. A release of cytokines necessary for the activation, maturation and survival of eosinophils, such as IL-4, IL-5 and IL-13 occurs in the activated Th-2 phenotype. In particular, IL-5 level is high in active EGPA and its inhibition has become a key therapeutic target. Oral glucocorticoids (OCS) are effective treatment options but unfortunately, frequent relapses occur in many patients and they lead to frequent side effects. As for now, there are currently no official recommendations on doses and treatment schedules in the management of EGPA. In this article, we describe the case of a man with EGPA, severe asthma and chronic rhinosinusitis with nasal polyps (CRSwNP), with poor asthma and CRSwNP control despite OCS and mepolizumab treatment. Respiratory and vasculitis symptoms improved markedly after therapeutic switch to benralizumab. During the treatment, in addition to clinical effects, we witnessed a depletion of blood eosinophils, as well as an improvement in both pulmonary function tests, CT scan and skin lesions present initially. While there are many studies confirming the efficacy of benralizumab in EGPA, the most interesting aspect of our report is that efficacy was confirmed in a patient previously unresponsive to mepolizumab, known to be effective in EGPA.