GlaxoSmithKline and Theravance Inc said on Friday that their combination therapy met the main goal of improving lung function in asthma patients in a late-stage trial.
The therapy consists of the corticosteroid, fluticasone furoate, which reduces inflammation, and a long-acting beta-agonist, called vilanterol, which is designed to open the airways.
The drug, already approved in the U.S. to treat chronic obstructive pulmonary disease (COPD) under the brand name Breo, proved more effective than fluticasone furoate alone for patients with moderate to severe asthma at the end of a 12-week treatment period.
The drug is inhaled through a palm-sized device called Ellipta. It is approved for both COPD and asthma in Europe, where it is sold as Relvar.
The most common side effects reported in the treatment period included headache, upper respiratory tract infection and influenza.
The drug is one of two new medicines GSK is relying on to reinvigorate its respiratory business as the company's $8 billion-a-year blockbuster Advair faces the threat of generic competition in the years ahead.
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