The FDA gave GlaxoSmithKline’s efforts to create an Ellipta franchise a boost with the approval of the asthma treatment Arnuity Ellipta (fluticasone furoate).

The daily inhaled corticosteroid is approved for asthma maintenance among patients 12 and up, and joins the new respiratory series which includes Breo Ellipta (fluticasone furoate and vilanterol powder) and Anoro Ellipta (umeclidinium and vilanterol powder) for COPD in the US. Breo Ellipta is indicated for COPD and asthma in Europe.

The drugmaker’s respiratory unit has been ailing—US respiratory sales fell 14% during the second quarter compared to the same period last year, and by 17% for the first six months of this year compared to the same period in 2013. Advair sales took a particular nosedive, falling 24% during the first six months of the year, to almost $1.7 billion, compared to the same six-month period in 2013. Advair’s patent is scheduled to expire in 2017, and concerns are that this IP lapse will drive the product’s performance even lower.

Payers and patients have not strongly taken to the new Ellipta drugs, and analysts anticipated a slow uptake even before Breo’s approval because the Advair franchise has been so effective. GlaxoSmithKline has been urging investors to give the company’s entire portfolio time to gain market confidence and build a stronger prescription base and is reaching out to consumers to do the same.

The company is also working towards filling out its offerings through efforts such as the Novartis asset swap in which GSK traded its oncology division in exchange for Novartis’s vaccines business, yet respiratory remains a focal point.

“Without a pick-up in switching to new respiratory portfolio products, we struggle to see a compelling value proposition in GSK particularly as competition is poised to intensify with new respiratory entrants… as well as the expected introduction of Advair generics in 2017,” Leerink analyst Seamus Fernandez wrote in his second-quarter earnings assessment in July.