Characteristics of patients with severe asthma who experienced treatment failure with omalizumab

Omalizumab, an anti-IgE antibody, has been widely used in many countries, including Japan. However, some patients do not respond to omalizumab, and the cause of treatment failure has not been fully elucidated.

This study aimed to evaluate the characteristics of adult asthma patients who failed to achieve disease control with omalizumab in a real-world setting.

We retrospectively reviewed the medical records of patients in Tokyo Women's Medical University Hospital between March 2009 and May 2016. The patient characteristics and factors for treatment failure with omalizumab were evaluated, as were treatment alternatives after discontinuation of omalizumab.

In total, 59 patients were included in this study. The omalizumab-ineffective group had a significantly higher number of patients with eosinophilic sinusitis (P = 0.001) and eosinophilic otitis media (P = 0.023) than the omalizumab-effective group. A multivariate analysis revealed that both eosinophilic chronic rhinosinusitis (odds ratio: 23.4; P = 0.011) and eosinophilic otitis media (odds ratio: 6.71; P = 0.039) were associated with treatment failure with omalizumab. Most patients with eosinophilic comorbidities of the ear, nose, and throat (ENT) in the omalizumab-ineffective group received mepolizumab or benralizumab as alternative therapy, following which disease control was achieved.

Eosinophilic comorbidities of the ENT may affect treatment failure with omalizumab in patients with severe asthma. Anti-interleukin-5 antibody or anti-interleukin-5Rα antibody rather than anti-IgE antibody should be considered as an additional therapy for patients with severe asthma who have eosinophilic comorbidities of the ENT.