Can GSK's latest respiratory hopeful deliver? FDA panel vote puts it one step closer

GlaxoSmithKline ($GSK) is working to get its now-underperforming respiratory newcomers up to speed, to fill in as blockbuster Advair declines. But it's hoping that the first in a new class of asthma meds will help pump up its top line, too--and on that front, it got one step closer late last week.

An FDA advisory panel endorsed Glaxo's latest respiratory treatment--the injectable med mepolizumab--for use in adults, voting 14-0 in favor of approval. The agency is set to make up its mind on the candidate by Nov. 4, and it usually takes its advisers' advice.

If it does, the approval would make mepolizumab the first IL-5 antibody out there, giving Glaxo a boost over respiratory competitors AstraZeneca ($AZN) and Teva ($TEVA), which are developing their own prospects. All three drugmakers plan to aim their therapies at COPD as well, which could build the IL-5 market beyond $7 billion a year, analysts have forecast.

GSK CEO Andrew Witty

And that's a lift GSK needs, especially in light of lackluster sales from new launches Breo and Anoro. Neither inhaled drug has so far come close to the blockbuster-level sales analysts have said they could reach, and though CEO Andrew Witty said earlier this year that the pair were finally making some market-share headway, he couldn't guarantee that the trend would continue throughout the year.

And that's a problem for the British pharma giant. Without its respiratory franchise doing its part to pitch in for freefalling Advair--whose U.S. sales plunged more than 20% in Q1 on payer hardships--it'll be left to rely on consumer health and vaccines, lower-margin businesses it beefed up through its recent Novartis ($NVS) asset-swap.

- read Glaxo's release

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