AstraZeneca and Amgen quietly admit tezepelumab setback as the Dupixent challenger heads to FDA
AstraZeneca and Amgen have blockbuster ambitions for their tezepelumab antibody, aiming to challenge the Regeneron and Sanofi giant Dupixent in asthma and related respiratory maladies. But as part of its second quarter update Thursday morning, the big British drugmaker quietly scuttled plans in another indication, raising doubt over how big a bite it will take out of the Dupixent pie.
After flunking two Phase II studies in atopic dermatitis, AstraZeneca dropped plans for tezepelumab to treat the condition altogether, the company revealed Thursday morning. The move comes just a few weeks after the antibody won priority review from the FDA in asthma, where a decision is expected in the first quarter next year.
Endpoints News has reached out to AstraZeneca for comment and will update accordingly.
Though tezepelumab has — mostly — passed all the necessary checkpoints in asthma, atopic dermatitis has been another story altogether. The first misstep came back in 2017, when the antibody whiffed on a Phase IIa primary endpoint in AD, coming up short on an eczema measurement scale compared to placebo.
In this study, tezepelumab was evaluated over a 12-week period in 113 patients with moderate to severe atopic dermatitis. Though a numerically greater portion of the drug arm saw improvement against placebo plus topical corticosteroids, the candidate missed statistical significance with a p-value of 0.091.
Then came a Phase IIb trial in 251 patients looking at both a monotherapy treatment course and an adjunct regimen, also in moderate to severe AD. This study was halted sometime in the second quarter of 2020 due to futility, according to Amgen’s earnings report at the time, with the pharma noting the study didn’t have any impact on asthma and COPD research.
By and large, that hypothesis has held true. AstraZeneca and Amgen won their priority review based on a Phase III study that cut the rate of severe asthma attacks on top of standard of care. Tezepelumab also managed consistent results regardless of patients’ baseline eosinophil counts and allergy status, an area where some analysts have suggested the antibody might have an advantage over the Regeneron/Sanofi giant.
But the program also flopped a separate Phase III study in the same population, a result Amgen R&D chief David Reese called “surprising” last December. Though Reese attributed the miss to possible trial design flaws, analysts took a more pessimistic look, noting that Dupixent had successfully reduced corticosteroid use in a similar trial.
As AstraZeneca and Amgen continue to chart a blockbuster path — some peak sales forecasts have pegged $2.5 billion annual sales for the antibody — they may struggle to reach the heights of competitors. Dupixent is approved to treat eczema and atopic dermatitis and overall sales increased a whopping 45% in the second quarter of 2021, Sanofi revealed Thursday.
That growth amounted to nearly $1.5 billion in the three-month period alone. It remains to be seen how quick the tezepelumab uptake will be, but AstraZeneca and Amgen are hoping for a quick and easy time at the FDA to get things going.