Mepolizumab cuts exposure to OCS in severe eosinophilic asthma

In patients with severe eosinophilic asthma, treatment with mepolizumab reduces exposure to toxic levels of oral corticosteroids (OCS) and, in turn, the incidence of associated complications, according to a real-world study.

Researchers used data from the Australian Mepolizumab Registry. They included 412 patients (median age 59 years, 58 percent female) with asthma that was uncontrolled despite optimized maximal therapy and elevated peripheral blood eosinophil levels.

Exposure to OCS was evaluated before and after starting mepolizumab. Toxic exposure was defined as a cumulative dose of ≥1,000-mg prednisolone equivalent. Patients completed the 5-item Juniper Asthma Control Questionnaire, Juniper Asthma Quality of Life Questionnaire – standardised (AQLQ[S]), and the Hospital Anxiety and Depression Scale (HADS).

The proportion of patients receiving OCS burst was 95 percent in the year prior to mepolizumab initiation, which dropped to 44 percent during second year of treatment (p<0.001). Most patients (64 percent) received toxic levels of OCS exposure in the year prior to treatment initiation, and these patients were more likely to receive a diagnosis of depression compared with those who received lower exposure levels (27 percent vs 15 percent; p=0.020). The percentage of patients with ongoing toxic level exposure decreased to 25 percent in the second year of mepolizumab treatment (p<0.001).

There were 42 percent of patients who required maintenance OCS at baseline, and this number dropped to 18 percent after 2 years of treatment (p<0.001).

More than a quarter of patients (37 percent) had a HADS-Depression score of ≥8 at baseline, which decreased to 15 percent after 2 years of mepolizumab (p<0.001). The number of patients with HADS-Anxiety score ≥8 also decreased, from 44 percent to 25 percent (p<0.001).

Notably, the improvements in HADS scores correlated with the improvement in AQLQ(S) score.