Amgen, AstraZeneca dig into data from phase 3 asthma trial, emerging with evidence of efficacy in hard-to-treat subgroup

Piece by piece, Amgen and AstraZeneca are building the case for their potential asthma blockbuster. The latest brick to fall into place comes from a new slice of phase 3 data, which suggests tezepelumab may be particularly effective in a subgroup of severe asthma patients. 

The pre-specified exploratory analysis comes from a phase 3 clinical trial that linked tezepelumab to statistically significant reductions in exacerbations in asthma patients, including individuals with low counts of a white blood cell who have limited treatment options. The exploratory analysis points to the potential for tezepelumab to move the needle in another hard-to-treat subgroup of patients.

Amgen and AstraZeneca divided the patients up based on whether they have nasal polyps, small growths found in patients with asthma and other respiratory diseases. Patients who have asthma and nasal polyps tend to be more prone to exacerbations and suffer from more airway obstruction.

In patients with severe uncontrolled asthma with reported nasal polyps who took tezepelumab, the annualized rate of asthma exacerbations was 0.39, compared to 2.76 in the placebo group. The difference amounted to an 86% reduction in exacerbations. The rate of exacerbations in patients without nasal polyps fell 52%, with the annualized rates in the tezepelumab and placebo groups clocking in at 0.98 and 2.05, respectively.

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The analysis, while exploratory, offers encouragement that tezepelumab is efficacious in patients with nasal polyps. That suggestion is supported by the improvements in nasal polyp symptoms seen in patients who received tezepelumab for 52 weeks.

"This new analysis from NAVIGATOR is exciting for the up to one in five severe asthma patients who have comorbid nasal polyps. The analysis shows tezepelumab's ability to reduce exacerbations, improve lung function and reduce the symptoms of nasal polyps in this comorbid population who are typically more prone to asthma attacks, have an increased likelihood of airway obstruction and may have a worse quality of life," Andrew Menzies-Gow, M.D., Ph.D., the principal investigator, said in a statement.

Amgen and AstraZeneca secured priority review at the FDA earlier this year, putting them on course to win approval for the thymic stromal lymphopoietin inhibitor in the first quarter. If approved, the drug could provide a new option for patients with low levels of eosinophil white blood cells. Existing asthma drugs such as Regeneron and Sanofi’s Dupixent and AstraZeneca’s Fasenra target eosinophilic forms of the disease. Patients with non-eosinophilic disease have limited treatment options.