- Amgen on Monday said it has submitted for Food and Drug Administration approval its asthma drug hopeful tezepelumab, advancing a medicine that's crucially important to its plans for growing beyond the aging blockbusters that have sustained its business for years.
- Tezepelumab, which Amgen has developed with partner AstraZeneca for nearly a decade, is a biologic drug that works to reduce airway inflammation in a new way. By blocking a protein known as TSLP, tezepelumab is thought to prevent the release of other, pro-inflammatory proteins, thereby reducing asthma attacks.
- Results from a study called NAVIGATOR, released in November, bore this hypothesis out, showing treatment with the drug reduced attacks in patients with severe asthma. But data from a much smaller clinical trial just one month later raised some questions about how competitive tezepelumab might be.
Amgen's submission to the FDA is on schedule and, should the agency accept the company's application, could set up an approval decision likely early next year.
Amgen is aiming for clearance to use tezepelumab in a broad population of people with severe asthma. The company estimates there are about 2.5 million patients worldwide whose condition isn't adequately controlled or who are eligible for biologic drug treatment. Approximately 1 million are in the U.S., according to the company.
In the NAVIGATOR study, adding tezepelumab to standard-of-care drugs reduced the annualized asthma attack rate by 56%. Among patients with lower levels of eosinophils, a type of white blood cell that is more prevalent in individuals with severe asthma, the reduction was 41%.
But in the other, smaller trial, called SOURCE, treatment with tezepelumab did not help reduce the daily dose of corticosteroids patients needed for their asthma — an outcome that Amgen's head of R&D David Reese said was "surprising."
If approved, tezepelumab would compete with Sanofi and Regeneron's top-selling drug Dupixent, among others. Previous testing showed treatment with Dupixent allowed for reduced steroid use.
Amgen will present further data on tezepelumab at the American Thoracic Society's international conference later this month.
"We think that the clinical profile of this molecule is quite attractive," said Amgen CEO Robert Bradway on a recent conference call with analysts. "My view continues to be that this is just going to be a really important medicine in asthma for patients."
It's a really important medicine for Amgen's business, too, as sales of once top-selling drugs like Enbrel and Neulasta fall. Overall, drug sales were down 5% year over year in the months from January to March, although the company attributed some of the declines to the impact of COVID-19 and lowered prices.
While several products, such as the cholesterol medicine Repatha, are growing, Amgen's counting on tezepelumab and a closely watched cancer drug called Lumakras to drive its business in the future. An FDA decision on Lumakras, which would be the first medicine for cancers driven to growth by mutations in a gene called KRAS, is expected by August.
Investors are also watching another cancer treatment called bemarituzumab, which Amgen acquired via a $1.9 billion buyout of biotech Five Prime Therapeutics in March.