The Biologics License Application (BLA) for tezepelumab has been submitted to the Food and Drug Administration (FDA) for patients with severe asthma.

Tezepelumab is an investigational first-in-class human monoclonal antibody that works by blocking thymic stromal lymphopoietin, an epithelial cytokine involved in the initiation and persistence of airway inflammation. 

The BLA submission is supported by data from the PATHFINDER clinical program, which included the double-blind, placebo-controlled phase 3 NAVIGATOR trial ( NCT03347279) that assessed the efficacy and safety of tezepelumab in 1061 patients 12 to 80 years of age with severe, uncontrolled asthma who were receiving medium- or high-dose inhaled corticosteroid plus at least 1 additional controller medication with or without oral corticosteroid. The study included patients with both high and low blood eosinophil counts.

Patients were randomly assigned 1:1 to receive tezepelumab or placebo administered by subcutaneous injection, in addition to standard of care. The primary end point of the study was the annualized asthma exacerbation rate during the 52-week treatment period.

Results showed that treatment with tezepelumab was associated with a statistically significant and clinically meaningful 56% reduction (95% CI, 47-63; P <.001) in annualized asthma exacerbation rate in the overall patient population compared with placebo.

A significant and clinically meaningful 41% reduction (95% CI, 25-54; P <.001) in annualized asthma exacerbation rate was also observed in tezepelumab-treated patients with baseline eosinophil counts less than 300 cells/µL; similar reductions were seen in patients with baseline eosinophil counts less than 150 cells/µL. 

As for safety, the most frequently reported adverse events with tezepelumab were nasopharyngitis, upper respiratory tract infection and headache.

The FDA previously granted Breakthrough Therapy designation to tezepelumab for this indication.


Amgen announces tezepelumab Biologics License Application submitted to U.S. FDA. [press release]. Thousand Oaks, CA: Amgen; May 10, 2021.