GSK within weeks of submitting Relovair for approval

GlaxoSmithKline (GSK) says it has completed phase III trials of its combination respiratory drug Relovair - a follow-up to its massive-selling Advair - and is planning to start regulatory filings in the middle of 2012.

The market's reaction to the news was muted however by a degree of disappointment about some of the top-line phase III data revealed by GSK.

The company's shares closed more than 4 per cent down yesterday, after some analysts said the results indicated Relovair (fluticasone and vilanterol)  performed no better than Advair/Seretide (fluticasone and salmeterol), and this could reduce its take-up if approved.

GSK's development partner for Relovair, US-based Theravance , saw a much more dramatic impact on share value from the negative results.

Theravance shares ended the day down a third as investors started to question whether GSK would now make a bid to buy the firm, something which had been rumoured ahead of the announcement.

Relovair is one of the most important products in GSK's pipeline as it starts to consider life once the revenue-generating power of Advair starts to decrease. The product accounted for around 9 per cent of GSK's total sales in 2010 but started to slow down in 2011.

In the first nine months of 2011, Advair pulled in £3.7bn, down 1 per cent overall and falling 3 per cent in the US.

GSK is racing to establish Relovair on the market before patents on Advair start to expire in Europe next year.

The company has always asserted, however, that generic rivals will struggle to gain headway because the Diskus inhaler device used with Advair provides a key competitive advantage.

Relovair has the advantage over Advair of once-daily rather than twice-daily dosing, thanks to the inclusion of 'ultra' long-acting beta agonist (LABA) vilanterol.

The company said yesterday it has completed all the phase III trials in its registration programme for Relovair in chronic obstructive pulmonary disorder (COPD) and is on track to file it for approval in this indication in both Europe and the US in mid-2012.

One phase III trial still has to be completed in asthma, but GSK expects to file in Europe in the coming weeks.

Meanwhile, in the US, GSK and Theravance will continue to discuss a market access strategy with the FDA, which has raised the safety bar for new asthma therapies of late in light of concerns about the safety of LABAs.