FDA panel backs AZ’s PT027 asthma rescue drug, but in adults only

AstraZeneca has moved a step closer to bringing a first-in-class drug to market in the US that can be used to reduce severe asthma attacks, after an FDA advisory committee voted in favour of approval.

PT027 is based on beta agonist albuterol and corticosteroid budesonide – two well-established therapies – combined into a fixed-dose inhaler that can be used as rescue medication when a patient with asthma is in the throes of an attack.

The FDA’s Pulmonary-Allergy Drugs Advisory Committee (PADAC) voted by 16 to one that PT027 should be approved for use in adults.

However, for adolescents aged 12 to 17 the panel voted by nine to eight that the data AZ submitted in support of the drug does not support approval. For younger children, the vote was 16 to one against, mainly on the grounds that there were too few patients in these age brackets in AZ’s clinical trials to give a meaningful view of efficacy.

The FDA is due to deliver a decision on the marketing application in the first half of next year, with AZ going after a broad label that would include all patients aged four and over.

One of the investigators in the PT027 programme, Bradley Chapps of the Capital Allergy & Respiratory Disease Centre in Sacramento, US, said that PT027 could “transform the current rescue treatment approach”, if approved.

“Millions of people with asthma rely on their albuterol rescue inhaler to alleviate acute symptoms, but this does not treat the underlying inflammation, leaving patients at risk of severe asthma exacerbations, regardless of their disease severity or level of control,” he added.

AZ is developing PT027 with UK partner Avillion under the terms of an agreement first signed in 2018. The two companies reported earlier this year that the fix-dose combination demonstrated a statistically significant reduction in the risk of a severe exacerbation versus albuterol rescue alone in patients with moderate to severe asthma in the MANDALA trial.

Results showed that PT027 at the 180mcg albuterol/160mcg budesonide dose reduced the risk of a severe exacerbation by 27% in adults and adolescents. Similarly, participants receiving the lower budesonide dose (180mcg albuterol/80mcg budesonide) saw a 17% reduction in the risk of severe exacerbation compared to albuterol rescue.

AZ and Avillion ran two other phase 3 trials – DENALI and TYREE – in support of the FDA filing, with the Katter also showing that PT027 led to improved lung function compared to either albuterol or budesonide used alone in patients with mild to moderate asthma.

Earlier this year, analysts at Jefferies predicted that the drug could reach $500 million in peak sales if approved, with the label sought.