AZ, Amgen file first-in-class asthma drug with the FDA

AstraZeneca (AZ) and Amgen have submitted a biologic license application (BLA) for their first-in-class asthma drug tezepelumab to the US Food and Drug Administration (FDA).

AZ and Amgen are seeking approval for tezepelumab for the treatment of severe asthma patients, based on results from the companies’ 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.

"Severe asthma remains uncontrolled for many patients despite current therapies for this complex and often debilitating condition," said David Reese, executive vice president of research and development at Amgen.

"This submission brings us one step closer to providing this potentially transformative treatment option to a broad population of severe asthma patients, across phenotypes and irrespective of biomarkers,” he added.

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 also added that tezepelumab is the only biologic to ‘consistently and significantly’ reduce AAER in a broad population of severe asthma patients irrespective of their baseline eosinophil counts across phase 2 and phase 3 trials.

In September 2018, tezepelumab scored a breakthrough therapy designation (BTD) from the US Food and Drug Administration (FDA) in patients with severe asthma without an eosinophilic phenotype.