The FTSE 100 firm has provided 530,000 doses ready for use on Monday at six hospital trusts, in Oxford, London, Sussex, Lancashire and Warwickshire.
Most other available doses will be sent to GP-led services and care homes later in the week.
‘I’m so pleased to be getting the COVID vaccine today and really proud it is one that was invented in Oxford.’
— NHS England and NHS Improvement (@NHSEngland) January 4, 2021
The country has established over 730 vaccination sites and hundreds more are opening this week to take the total to over 1,000.
The government has secured access to 100mln doses of the inoculation on behalf of the whole of the UK, crown dependencies and overseas territories.
More than a million people in the UK have already been vaccinated with the Pfizer/BioNTech vaccine and its rollout will continue at pace.
However, there has been criticism of the government’s plan since the required two doses of both jabs will now be administered 12 weeks apart.
The British Medical Association said cancelling patients booked in for their second doses was “grossly unfair”, the BBC reported, though the chief medical officers said it is preferable to vaccinate as many as people as possible with the first dose.
Meanwhile, AstraZeneca has applied to get the jab approved in South Korea, while Vietnam has bought 30mln doses and is in talks with other companies to purchase more.
Shares in the pharma giant jumped 3% to 7,514p on Monday morning.