The London-based drug maker presented the study results at the European Respiratory Society, it said in a statement on Monday.
AstraZeneca said it aims to file for regulatory approval of the medicine for severe asthma patients in the US and Europe this year.
The studies showed up to 51% reductions in the annual rate of asthma exacerbation, the company said.
Benralizumab would compete with GlaxoSmithKline’s Nucala. Both treatments reduce eosinophils, the cells that drive inflammation in about half of asthma patients.
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