The pharmaceutical group reported a £1.42 billion year-on-year increase in turnover in the three months to September, £925 million of which was attributed to the exchange rate

GlaxoSmithKline has collected a £1 billion windfall from the collapse in sterling, making it one of the biggest winners since the EU referendum.

The pharmaceutical group reported a £1.42 billion year-on-year increase in turnover in the three months to September, £925 million of which was attributed to the exchange rate.

Glaxo was well placed to benefit because a large share of its manufacturing, but just 4 per cent of sales, occurs in Britain. Since the referendum in June the pound has fallen 15 per cent against other currencies.

Sir Andrew Witty, the outgoing chief executive who hands over to Glaxo’s consumer health boss Emma Walmsley in March, acknowledged that the immediate impact of Brexit had been good for business.

“Over many years we have retained