The US Food and Drug Administration (FDA) has granted approval to United Kingdom-based AstraZeneca, along with its wholly owned subsidiary, MedImmune, for Fasenra (benralizumab) intended for the treatment of severe eosinophilic asthma, it was reported yesterday.

The product has been approved as an add-on maintenance treatment for patients aged 12 years and older with severe asthma, and with an eosinophilic phenotype. It is a monoclonal antibody that deploys natural killer cells to induce direct, rapid and near-complete depletion of eosinophils. It is claimed to be the only respiratory biologic that can decrease eosinophils within 24 hours.

The approval was based on data from the Windward program that includes Phase III exacerbation trials, Sirocco and Calima, and the Phase III oral corticosteroid- sparing trial called Zonda. According to the firm, the studies indicated up to 51% reduction in the annual asthma exacerbation rate compared to placebo, and significant improvement in lung function as measured by forced expiratory volume in one second of up to 159mL against placebo.