GSK is expecting an asthma indication for Trelegy.

Asthma drug Advair (fluticasone propionate) from GlaxoSmithKline (GSK) is used by millions of people around the world. It is a top drug in GSK’s portfolio, but is facing significant pricing pressure from insurers and growing competition from generics.

TRELEGY ELLIPTA (fluticasone furoate, umeclidinium, and vilanterol inhalation powder) is the only branded once-daily triple therapy in a single inhaler that is approved for the long-term treatment of chronic obstructive pulmonary disease (COPD). GSK received approval from the U.S. Food and Drug Administration (FDA) in 2017.

Now the company is hoping Trelegy will get approved for the treatment of asthma and replace some of the revenue generated by Advair.

The company recently reported the phase III results of Trelegy in asthma, which showed that it outperformed Breo Ellipta, known as Relvar in Europe, with respect to improving lung function after 24 weeks in patients with uncontrollable asthma. It failed, however, to hit its secondary endpoint: an improvement over Breo with respect to reducing the incidence of episodes where symptoms suddenly worsen.

Despite these mixed results, GSK will be submitting the data to the FDA for approval of Trelegy as a once-daily single inhaler triple therapy that improves lung function in patients with uncontrolled asthma. The company believes having this option, which is currently not available, will be a real advance for patients, according to Hal Barron, Head of R&D at GSK.