AstraZeneca has reported positive full results from its phase 3 NATRON trial evaluating Fasenra (benralizumab) for the treatment of hypereosinophilic syndrome (HES).
HES is a group of rare disorders characterised by persistently elevated levels of eosinophils – a type of white blood cell – in the blood, accompanied by evidence of tissue or organ damage. Symptoms range from fatigue and weight loss to more severe outcomes such as organ failure or coma. Owing to this variety, diagnosis can be challenging; estimates suggest HES affects between 0.04 and 0.17 per 100,000 people in the UK.
The multicentre, randomised, double-blind, placebo-controlled NATRON study assessed the efficacy and safety of 30mg of Fasenra administered subcutaneously every four weeks in eligible patients with HES.
The trial met its primary endpoint, demonstrating a statistically significant and clinically meaningful delay in time to first disease worsening or flare, and a reduction in overall risk of flare compared with placebo.
All key secondary endpoints were also met, including a lower proportion of patients experiencing flare-ups or withdrawing from treatment, and a reduction in the annualised flare rate versus placebo. Improvements in fatigue scores were additionally observed.
Sharon Barr, Executive Vice President, BioPharmaceuticals R&D, AstraZeneca, said: “The NATRON results confirm Fasenra’s ability to address eosinophilic inflammation in difficult to treat eosinophilic-driven diseases, like HES and eosinophilic granulomatosis with polyangiitis, in addition to severe eosinophilic asthma.
“By sharing the full results from NATRON with the medical community today and progressing our regulatory filing, we hope to realise a future in which Fasenra helps patients with HES who currently have very limited options.”