Today, GSK released disappointing clinical results for a new respiratory drug it hoped would bring in billions of pounds worth of sales.
Breo, a treatment for asthma and chronic obstructive pulmonary disease (COPD), managed to extend life expectancy by just 12.2 per cent among a patient sample size of 16,500 from 43 countries around the world.
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Although this is a slight improvement compared with having no treatment at all, the difference is too small to be considered statistically significant.
The news doesn't bode well for sales of the medicine, which had originally been expected to reach $1.5bn (£980m) by 2020, according to Thomson Reuters Cortellis.
Co-developed with US biopharma company Theravance, the inhaled medicine was first approved to treat the disease in Europe and the US in 2013. GSK has been hoping to use it to replace its flagship drug Advair, which has suffered a decline in sales due to stiff competition from cheaper generics.
Breo is considered an improvement on Adavir because it requires only one dose a day, compared to two doses for the latter.
Shares in the UK pharmaceutical giant were hit by this morning's news, initially falling 1.5 per cent. Shares in Nasdaq-listed Theravance, meanwhile, plunged 15 per cent in pre-market trading.
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