GSK invests further $212.9m in Theravance

GlaxoSmithKline (GSK) has increased its investment in Theravance by $213.9m, giving the UK pharma firm a 26.8 per cent stake in its US biopharma partner.

GSK and Theravance's have been working together since 2002 and while the UK company has previously increased its share in Theravance it has never done so on this scale.

The agreement sees GSK complete the purchase of 10,000,000 Theravance shares at a cost of $21.29 per share, with GSK now owning a total of 25,814,421 shares of Theravance common stock.

The move indicates GSK's increased confidence in its respiratory medicine Relovair, which the company is developing with Theravance with an aim to replace its big-selling Seretide (marketed as Advair in the US).

This is despite concerns over Relovair, which is being investigated in the treatment of asthma and chronic obstructive pulmonary disease (COPD), being raised in both January and March following the publication of disappointing data from phase III trials.

GSK and Theravance had struggled to show that Relovair was unequivocally superior to Seretide in treating COPD, although data from another phase III trial in asthma, comparing both drugs to placebo is still to be released and GSK is also working with the NHS on a 'real world' data study.

The companies are pressing ahead with regulatory filings for Relovair with a view to easing the pain of Seretide's loss of exclusivity. Its patent is due to expire in 2013, at which point a significant portion of the drug's $5.1bn annual global revenue will be lost to generic competition.

Despite its inability to show superiority over its predecessor, Relovair's once-daily dosing regime could still give it an advantage over Seretide and any future generic versions, which have to be taken twice a day.

Marketing applications for Relovair's use in COPD will be submitted in the US and Europe in mid-2012, while GSK plans to submit an application for asthma in Europe in mid-2012.

The company said it will also continue discussions with the FDA regarding regulatory requirements for a US asthma indication.