FDA grants priority review for AZ, Amgen’s tezepelumab for asthma

The US Food and Drug Administration (FDA) has accepted AstraZeneca (AZ) and Amgen’s submission for their investigational asthma drug tezepelumab and granted a priority review for the therapy. 

Tezepelumab is a potentially first-in-class thymic stromal lymphopoietin (TSLP) targeting antibody – TLSP is a key epithelial cytokine that initiates an overactive immune response to allergic, eosinophilic and other types of airway inflammation and is associated with severe asthma.

AZ and Amgen’s drug acts further upstream in the inflammatory cascade responsible for asthma, meaning it may '[help] stop inflammation at the source and has the potential to treat a broad population of severe asthma patients”'.

The companies’ FDA submission for tezepelumab for the treatment of severe asthma patients is based on results from the PATHFINDER clinical programme.

This includes data from the pivotal phase 3 NAVIGATOR trial, which demonstrated that tezepelumab achieved a 56% reduction in the annual asthma exacerbation (AAER) rate over 52 weeks in the overall patient population when added to standard of care (SoC).

In this trial, SoC was defined as medium- or high-dose inhaled corticosteroids (ICS) plus at least one additional controller medication, with or without oral corticosteroids (OCS).

In addition, a pre-planned subgroup analysis showed that tezepelumab achieved a 41% reduction in AAER in patients with baseline eosinophil counts of less than 300 cells per microlitre.

Clinically meaningful reductions in AAER were observed in tezepelumab-treated patients regardless of allergy status and fractional exhaled nitric oxide (FeNO) level – biomarkers used by clinicians to inform treatment options.

“This decision brings us a step closer to delivering a much-needed, first-in-class medicine for asthma patients, many of whom remain uncontrolled and at risk of asthma attacks despite the availability of inhaled and biologic medicines,” said Mene Pangalos, executive vice president, BioPharmaceuticals R&D at AZ.

"Tezepelumab has demonstrated reductions in exacerbations irrespective of blood eosinophil counts, allergy status and fractional exhaled nitric oxide, and has the potential to transform treatment for a broad population of severe asthma patients," he added.

In September 2018, tezepelumab received a breakthrough therapy designation (BTD) from the FDA in patients with severe asthma without an eosinophilic phenotype.

The FDA’s decision on the approval of tezepelumab is expected in the first quarter of 2022, AZ said in a statement.