AstraZeneca will move finance chief Marc Dunoyer to head newly acquired rare diseases business Alexion, using the $39 billion takeover as an opportunity to freshen up a management team that had been in place for eight years.

Chief Executive Pascal Soriot has faced heavy public criticism and EU legal action after AstraZeneca missed targets for coronavirus vaccine deliveries, with he and Dunoyer also attracting investor anger over their pay packages last month.

Dunoyer will replace Ludwig Hantson as boss of United States-based Alexion on completion of the agreed deal, with the proposed switch allowing Aradhana Sarin to move in the opposite direction and become AstraZeneca chief financial officer.

The Anglo-Swedish drugmaker agreed in December to buy Alexion in a bet on rare-disease immunology to add to its fast-growing cancer medicines unit and a major Covid-19 vaccine.

London-listed AstraZeneca said Sarin's appointment is also conditional upon completion of the Alexion deal, which was approved by shareholders last month.

Britain and the European Union are reviewing the deal, which gained US approval in April.

As well as becoming Alexion chief executive, Dunoyer will also be appointed chief strategy officer at AstraZeneca.

He will leave the board but continue to report to Soriot.

Soriot and Chairman Leif Johansson have been in their roles since 2012 and Dunoyer was appointed in late 2013.

In an interview with the Financial Times last month, Soriot indicated that succession planning had begun for the three men at the top.