The drug, tezepelumab, is an injectable treatment that is expected to help a wider range of patients than existing asthma medicines like GlaxoSmithKline Nucala.
A breakthrough therapy status is designed to expedite the development and regulatory review of medicines that are intended to treat a serious condition and that have shown encouraging early clinical results.
A mid-stage trial in 2017 of 584 patients showed that tezepelumab reduced the annual rate of serious asthma attacks, known as exacerbations, by between 61 percent and 71 percent, depending on dose.
Tezepelumab is currently in late-stage trials.
The drug has shown promise in treating "a broad population of patients with severe asthma, including those ineligible for currently approved biologic therapies," said David Reese, executive vice president of Research and Development at U.S.-based Amgen.
(Reporting by Nivedita Balu in Bengaluru; Editing by Sai Sachin Ravikumar)