The US Food and Drug Administration (FDA) has granted Breakthrough Therapy Designation to AstraZeneca (LON: AZN) and its partner Amgen Inc (NASDAQ: AMGN) for tezepelumab as a treatment for patients with severe asthma, without an eosinophilic phenotype, who are receiving inhaled corticosteroids/long-acting beta2-agonists with or without oral corticosteroids and additional asthma controllers, the multinational pharmaceutical company announced on Friday.

Tezepelumab is a potential first-in-class new medicine that blocks thymic stromal lymphopoietin (TSLP), an upstream modulator of multiple inflammatory pathways.

The aim of the Breakthrough Therapy Designation is to expedite the development and regulatory review of medicines that are intended to treat a serious condition and have shown encouraging early clinical results.

Data from the Phase IIb PATHWAY trial was used to form the decision to grant the Breakthrough Therapy Designation. The trial demonstrated that tezepelumab resulted in a significant reduction in the annual asthma exacerbation rate compared with placebo in a broad population of severe asthma patients, irrespective of patient phenotype, including Type 2 (T2) biomarker status.

Current biologic therapies only target T2-driven inflammation.

AstraZeneca and Amgen are currently developing tezepelumab in the Phase III PATHFINDER clinical trial programme.