Mepolizumab reduces oral corticosteroid exposure in severe eosinophilic asthma patients
Published online: July 1, 2021
Although the adverse health consequences of oral corticosteroids (OCS) are increasingly recognised, they remain the mainstay therapy for the management of exacerbations in patients with severe asthma. While OCS therapy effectively manages acute episodes, serious side-effects affecting most of the systems in the body contribute to significant disease burden, highlighting the importance of OCS stewardship initiatives. Strategies that can minimise OCS use while managing asthma are crucial to limit the lifelong impacts of OCS therapy. Previous studies have shown that mepolizumab, a monoclonal antibody, has a significant OCS sparing effect and reduces the number of exacerbations requiring OCS treatment.
In a recent article in The Journal of Allergy and Clinical Immunology: In Practice, Thomas et al report the results of an observational study that comprehensively evaluated the pattern of OCS use in 309 patients with severe eosinophilic asthma before and after starting mepolizumab therapy. They assessed both long-term exposure (maintenance OCS to prevent exacerbations) and short-term exposure (OCS bursts to manage exacerbations) 12 months before and after starting mepolizumab therapy. The authors also explored the predictors of becoming OCS free after 6 months of treatment with mepolizumab.
The authors found that OCS use was extremely high among participants in the 12 months before starting mepolizumab therapy. Almost all patients (96%) experienced at least one exacerbation that required OCS therapy, and half (48%) were on maintenance OCS therapy at the baseline interview, representing a high-burden cohort with extreme risk of OCS side effects. After starting mepolizumab therapy, there was a significant and sustained reduction in short-term and long-term OCS use. Almost half of the patients stopped maintenance OCS use, and among those who stopped, half did so within six months of commencing mepolizumab therapy. The maintenance OCS dose reduced from a median of 10 (IQR 5.0, 12.5) mg/day at baseline to 2 (0, 7.0) mg/day at 12 months (P < .001). Short-term OCS use also reduced by half (96% vs 50%). Notably, the reduction in OCS use did not affect asthma symptom control. These findings support the OCS sparing effect of mepolizumab and its pivotal role in OCS stewardship initiatives. A greater asthma control at baseline, late onset of asthma symptoms, absence of maintenance OCS use at baseline and lower body mass index were significant predictors of becoming OCS free after six months of treatment with mepolizumab.
In summary, severe asthma patients are exposed to large doses of OCS to prevent and manage exacerbations, which requires urgent attention. Biological therapies such as mepolizumab reduce OCS use while minimising exacerbations and should be considered in the development and implementation of OCS stewardship initiatives in people with severe eosinophilic asthma.
The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.