The investment will go to sites at Barnard Castle in County Durham, Montrose in Scotland, and Ware in Hertfordshire, and GSK said "new employment opportunities" are expected to be created as a result.
Chief executive Andrew Witty said the pharmaceutical giant came to its decision because of the UK’s competitive corporate tax system and skilled workforce helped the
Mr Witty, who backed the Remain campaign during the EU referendum, said: "Today's announcement reflects further investment to support our pharmaceutical pipeline and meet growing demand for our innovative portfolio of newly launched products.
"It is testament to our skilled UK workforce and the country's leading position in life sciences that we are making these investments in advanced manufacturing here. From their manufacture in the UK, many of these medicines will be sent to patients around the world."
Business and Energy Secretary Greg Clark said: "An investment of this scale is a clear vote of confidence in Britain and underlines our position as a global business leader.
"GSK's recognition of our skilled workforce, world leading scientific capabilities and competitive tax environment is further proof that there really is no place better in Europe to grow a business."
UK Government Minister Andrew Dunlop said: “It is great news that GlaxoSmithKline is boosting investment in Scotland, and a real testament to the hard work and skills of the workforce in Montrose. Above all, it is a clear vote of confidence in the country’s economy, and shows that Scotland and the UK are very much open for business."
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