UPDATED: GSK, Theravance share mixed bag of lung drug data ahead of FDA filing

GlaxoSmithKline ($GSK) and partner Theravance ($THRX) have dropped another up-and-down set of data related to development of their blockbuster hopeful Relovair today. Yet the duo remains on schedule to file for U.S. and European approval of the drug for chronic pulmonary obstructive disorder (COPD) by mid-2012, the companies said.

The important data in today's release are the non-pivotal results of two studies that compared Relovair taken once a day to GSK's blockbuster lung treatment Advair taken twice per day. Relovair, an inhaled treatment, provided statistical superiority in a breathing test in one of the studies but not in the other. This is par for the course in this elaborate development program: These data follow others that provided mixed results. 

Meantime, GSK said that it expects to seek regulatory approval for the drug as an asthma treatment in Europe in mid-2012, and it's in talks with U.S. regulators about its FDA submission.

The Relovair program has emerged as one of the most closely watched in London-based GSK's extensive pipeline, as the drug is expected to eventually replace Advair. Reuters reports that Advair had sales last year of $8 billion, making it the drug giant's biggest blockbuster. GSK CEO Andrew Witty (photo) has reportedly talked up the company's future sales prospects, and he's bet heavily on a combo of internal R&D efforts and external partnerships like the Relovair tie-up with Theravance.

For South San Francisco-based Theravance, there is much more at stake with the Relovair program. In fact, the company's stock is down about 15% this year after troubling safety data from the program revealed in early January caused the company's stock to tank.

- here's the companies' release
- check out the Reuters report

Correction: This story incorrectly stated that Theravance has no products on the market. The company has one drug on the market, Vibativ, an antibiotic for skin infections. We apologize for the error.