Persistence of Sinonasal Disease Despite Mepolizumab

The treatment paradigm for the management of chronic rhinosinusitis with nasal polyposis (CRSwNP) is currently undergoing a rapid evolution with the development of monoclonal antibody therapies targeted at type 2 inflammatory pathways. The use of these biologic therapies in asthmatic patients, and more recently, patients with CRSwNP has produced promising results, especially for patients with severe disease. Many questions regarding the appropriate timing of these medications, whether or not these new treatment strategies should be used as a monotherapy or in conjunction with traditional therapies such as sinus surgery, the role of appropriate phenotyping, and identification of biomarkers, remain unanswered. We herein present a case of a patient with severe eosinophilic asthma and comorbid CRSwNP who failed to achieve control of his respiratory symptomology and ultimately progressed to sinus surgery despite treatment with an anti-interleukin 5 monoclonal antibody therapy (mepolizumab). Consideration is given to the mechanistic underpinnings of the reported patient's failure. This case highlights the need for further understanding of the optimal usage of these novel therapeutics in the management of CRSwNP and in the need to better understand the pathophysiology of CRSwNP.