This article is more than 5 years old. Information may no longer be current.

Mepolizumab reduced exacerbations, glucocorticoid dosing in patients with eosinophilic asthma

Mepolizumab, administered subcutaneously or intravenously, reduced exacerbations and glucocorticoid dosing in patients with eosinophilic asthma, according to results of two recent studies.

“These data help build our understanding of the potential role of mepolizumab in the management of severe eosinophilic asthma,” Elisabeth H. Bel, MD, PhD, University of Amsterdam, said in a press release. “Its potential to reduce the steroid burden that many patients endure, coupled with patients reporting that they actually feel better, are both important for patients and physicians.”

Mepolizumab (GlaxoSmithKline) is an investigational interleukin-5 antagonist monoclonal antibody.

In Bel’s study, she and colleagues compared 100 mg mepolizumab with placebo administered subcutaneously every 4 weeks for 20 weeks in 135 patients (mean age, 50 years) with severe eosinophilic asthma. Reduction in glucocorticoid dose was the primary outcome; asthma exacerbation rate, asthma control and safety also were measured.

The mepolizumab-treated cohort had a 2.39 greater likelihood of reduced glucocorticoid dosing compared with placebo patients (95% CI, 1.25-4.56). Patients assigned mepolizumab had a 50% median reduction in glucocorticoid dose vs. 0% in placebo patients (P=.007). Safety profiles were similar between mepolizumab and placebo.

“Despite receiving a reduced glucocorticoid dose, patients in the mepolizumab group, as compared with those in the placebo group, had a relative reduction of 32% in the annualized rate of exacerbations (1.44 vs. 2.21; P=.04) and a reduction of 0.52 points with respect to asthma symptoms (P=.004), as measured by the Asthma Control Questionnaire (in which the minimal clinically important difference is 0.5 points),” the researchers wrote.

In the second trial, researchers conducted a double blind study of 576 patients with recurrent asthma exacerbations and eosinophilic inflammation who were randomly assigned 75 mg intravenous mepolizumab (IM) or 100 mg subcutaneous mepolizumab (SM) or placebo every 4 weeks for 32 weeks. Rate of exacerbations was the primary outcome. Forced expiratory volume in 1 second (FEV₁) and St. George’s Respiratory Questionnaire (SGRQ) and the Asthma Control Questionnaire (ACQ-5) scores were other outcomes. Five hundred thirty-nine patients completed treatment.

Compared with the placebo cohort, asthma exacerbation was reduced by 47% (95% CI, 29%-61%) in IM patients and by 53% (95% CI, 37%-65%) in the SM cohort (P<.001, for both). ED visits or hospitalizations due to exacerbations were reduced by 32% in the IM cohort and by 61% in the SM group.

“At week 32, the mean increase from baseline FEV₁ was 100 mL greater in patients receiving [IM] than in those receiving placebo (P=.02) and 98 mL greater in patients receiving [SM] than in those receiving placebo (P=.03),” the researchers wrote.

The SGRQ score improvement from baseline was 6.4 points and 7 points greater in the IM and SM cohorts, respectively, compared with placebo patients, surpassing the minimal clinically important change threshold (P<.001, both). ACQ-5 scores were 0.42 points and 0.44 points greater in the IM and SM cohorts, respectively, compared with placebo treatment (P<.001, both).

Safety profiles for mepolizumab and placebo were similar.

“Mepolizumab administered either intravenously or subcutaneously significantly reduced asthma exacerbations and was associated with improvements in markers of asthma control,” the researchers concluded.

Disclosure: See the studies for full lists of relevant financial disclosures.