Rapid effect of benralizumab for severe asthma with chronic rhinosinusitis with nasal polyps

Background: The anti-interleukin (IL)-5 agent benralizumab has recently become available for treatment of severe asthma with promising results; however, it appears effective only in specific subgroups of asthma patients. Severe asthma with chronic rhinosinusitis/nasal polyps (CRSwNP or eosinophilic chronic rhinosinusitis, ECRS) is a severe eosinophilic asthma phenotype that necessitates individualized treatment. Objective: To assess differences in response to benralizumab between severely eosinophilic asthma patients with and without CRSwNP. Methods: Seventeen outpatients with severe eosinophilic asthma treated with benralizumab for 1 year were evaluated at the Osaka Habikino Medical Center. Blood eosinophil count, Asthma Control Questionnaire 5 (ACQ5), Asthma Quality of Life Questionnaire (AQLQ), fractional exhaled nitric oxide (FeNO), and spirometry were recorded at weeks 0, 4, 16, 24, and 50. Results: ACQ5 and AQLQ in CRSwNP(+) groups improved significantly after 4, 16, 24, and 50 weeks (p = 0.0195, 0.0156, 0.0117, and 0.0078 and p = 0.0098, 0.0098, 0.0029, and 0.0098, respectively) of benralizumab treatment. ACQ5 in CRSwNP(-) groups did not improve significantly after benralizumab treatment, but AQLQ improved significantly after 24 (p = 0.0313) and 50 weeks (p = 0.0313). Forced expiratory volume in 1s (FEV1) predicted in CRSwNP(+) groups were improved significantly after 4 weeks (p = 0.0137), 16 weeks (p = 0.0127), 24 weeks (p = 0.0098) and 50 weeks (p = 0.0420) of benralizumab treatment. %FEV1 in CRSwNP(-) groups were improved significantly after 24 weeks (p = 0.0313) and 50 weeks (p = 0.0313) of benralizumab treatment (Fig. 3). Forced vital capacity (FVC) predicted in CRSwNP(+) groups were improved significantly after 24 weeks (p = 0.0195) and %FVC in CRSwNP(-) groups improved significantly after 50 weeks (p = 0.0313) of benralizumab treatment. Maximum mid-expiratory flow rate predicted in CRSwNP(+) groups were improved significantly after 16 (p = 0.0137 and 50 weeks (p = 0.0371) of benralizumab treatment. Conclusions: Benralizumab can exert a very rapid therapeutic action, detectable 4 weeks after treatment initiation in patients with severe eosinophilic asthma with CRSwNP. However, severe eosinophilic asthma without CRSwNP takes longer to respond to benralizumab treatment.