A swine flu vaccine windfall worth £92.3m contributed to a leap in third-quarter profits at drug giant AstraZeneca, the group revealed today.

AstraZeneca said it saw a 23% hike in profits and 10% rise in sales, helped in part by sales of its H1N1 vaccine as it began shipping doses earlier this month under the US immunisation programme.

The group has been signed up to deliver 40m doses of the vaccine to the US for £275m.

Vaccine sales in the third quarter accounted helped Astra bank sales of £5bn, with pre-tax profits rising to £1.84bn.

The rest of the swine flu vaccine sales cash is due in the next three months and Astra today upped its full-year earnings guidance as a result of stronger-than-expected figures.

Fellow pharmaceutical firm GlaxoSmithKline yesterday confirmed expectations for £1bn in swine flu vaccine sales in the fourth quarter alone.

Governments begun their immunisation programmes this month, prioritising the high risk groups as they step up their battle against a feared winter surge in the pandemic.

There were an estimated 78,000 new cases of swine flu in England in the past week, up from 53,000 in the week before.

Astra has secured relatively small numbers of orders for swine flu, with its 40m US contract dwarfed by GlaxoSmithKline’s 440m orders so far.

But Astra said recent additional orders had come in at the top end of its estimates, leading to the increase in its annual earnings targets.

The firm – headquartered in Macclesfield, Cheshire – is also benefiting from continued strong demand for its cholesterol drug Crestor.

Sales of the treatment rose 30% at constant exchange rates, while its heart drug Toprol saw sales more than double thanks to delays in rival generic versions.