Mepolizumab Found to Improve Lung Function and Decrease Exacerbations in Severe Eosinophilic Asthma

Researchers sought to determine whether select baseline patient characteristics could prognosticate mepolizumab effectiveness in patients with severe eosinophilic asthma.

Patients with severe eosinophilic asthma taking mepolizumab saw fewer exacerbations and improvements in lung function compared to patients taking placebo, according to the results of a recent study published in Respiratory Research.

Clinical outcomes were measured during the phase 3 MENSA and MUSCA clinical trials in patients older than 12 years with severe eosinophilic asthma. Study participants were given either placebo or mepolizumab (either 75 mg intravenously in the MENSA study or 100 mg subcutaneously in MUSCA).

Treatment duration was 32 weeks for the MENSA study and 24 weeks for the MUSCA study. The primary endpoint was the annual rate of clinically significant exacerbations, whereas secondary endpoints included changes from baseline in prebronchodilator forced expiratory volume in 1 s (FEV1) and scores on the St George’s Respiratory Questionnaire and Asthma Control Questionnaire.

Among the 936 participants enrolled in the studies, 468 received placebo and 468 received mepolizumab. In the primary study outcome, mepolizumab was associated with reductions of 49% to 62% in the annual rate of clinically significant exacerbations compared with placebo across all age groups.

Patients receiving mepolizumab were also more likely to experience no clinically significant exacerbations during the study. Mepolizumab also resulted in an increase from baseline in prebronchodilator FEV1 versus placebo in all age of asthma onset subgroups.

The study authors wrote, “Mepolizumab efficacy was consistent for patients with varying age at asthma onset, lung function, airway reversibility and allergen sensitivities at baseline.” They added “Our results indicate that mepolizumab is likely to be beneficial for patients with severe eosinophilic asthma with a broad range of baseline clinical characteristics; however large-scale real-world studies are needed to confirm the external validity of these findings.”

Disclosure: This clinical trial and several study authors was supported by industry. Please see the original reference for a full list of authors’ disclosures.


Lemiere C, Taillé C, Lee JK, et al. Impact of baseline clinical asthma characteristics on the response to mepolizumab: a post hoc meta-analysis of two phase III trials. Respir Res. 2021;22(1):184. Published June 22, 2021. doi:10.1186/s12931-021-01767-z