Drugs giant GlaxoSmithKline is to increase its stake in US biopharmaceutical company Theravance.Theravance will issue 10m shares to Glaxo at $21.2887 per share, meaning the UK company will spend $212.9m to up its stake in Theravance from 18.3% to 26.8%. The price per share was a 7.5% premium to the average price per share of Theravance common stock over the five-day period ending March 30, which was $19.8034. The two companies have been collaborating since 2002 on drugs development, including work on Relovair, seen as a successor to Glaxo's top-selling inhaled lung treatment Advair.Relovair has now completed its Phase III development and Glaxo intends to submit regulatory applications for chronic obstructive pulmonary disease in the US and Europe in mid-2012. For the treatment of asthma using Relovair, Glaxo also plans to submit an application in Europe in mid-2012 and will continue discussions with the US Food and Drug Administraton on the regulatory requirements for a US asthma indication.NR/JH