AstraZeneca has been boosted by positive mid-stage data on benralizumab for severe, uncontrolled asthma.

The Phase IIb study, data from which has been published in The Lancet Respiratory Medicine, evaluated adult patients with severe eosinophilic asthma that remained uncontrolled despite the use of inhaled corticosteroids and long-acting beta agonists for at least one year, and who had experienced at least two exacerbations in the past year. The trial met its primary endpoint, with patients on benralizumab experiencing a statistically significant reduction in their asthma exacerbation rate versus placebo over a year.  

Specifically, the study showed that benralizumab reduced asthma exacerbations by approximately 40%-70% depending on the dose received and baseline blood eosinophil (a type of white blood cell) level. AstraZeneca noted that the study also met its secondary endpoints -  improvements in lung function and asthma control.

Frequencies of adverse events were similar within the benralizumab and placebo groups. Common cold and skin reactions at the injection site occurred more frequently with the drug than with placebo.

Mario Castro of the Washington University School of Medicine and lead investigator of the trial, said activity may be related to the fact that benralizumab “uniquely targets the IL-5 receptor versus the ligand, efficiently reducing eosinophils, a key contributor to asthma symptoms”.

Bing Yao, head of respiratory, inflammation and autoimmunity operations at AstraZeneca’s MedImmune unit, said asthma is “a highly heterogeneous disease and these data advance our understanding of patient subtypes, potential biomarkers and targeted therapies”.

Benralizumab is in Phase III for severe, uncontrolled asthma and chronic obstructive pulmonary disease. AstraZeneca noted that “a personalised healthcare strategy is included in the trial design” where a simple blood test is used to identify patients with elevated blood eosinophils who are most likely to respond to therapy.