More than £15 billion was wiped from AstraZeneca’s market value on Monday after reports that the pharmaceutical group has held talks over a potential US$400 billion merger with US rival Bristol Myers Squibb.
AstraZeneca shares fell 7.6% to their lowest level since October as investors reacted to the prospect of one of the largest corporate combinations ever attempted.
The Cambridge-based drugmaker is currently valued at around £184 billion, while New York-listed Bristol Myers Squibb has a market capitalisation of approximately US$133 billion.
A completed deal would create one of the world’s largest pharmaceutical companies, but it would also raise fresh questions over AstraZeneca’s long-term ties to the UK.
Chief executive Pascal Soriot has increasingly expanded the group’s US presence. AstraZeneca upgraded its New York listing last year and subsequently committed US$50 billion to American manufacturing and research facilities.
Despite its growing US focus, the company has maintained that it intends to keep its headquarters in Cambridge and retain its London Stock Exchange listing.
Any transaction would likely attract close political and regulatory scrutiny in Britain, reviving memories of Pfizer’s unsuccessful attempt to acquire AstraZeneca more than a decade ago.
AstraZeneca employs around 10,000 people across five UK sites, including major operations in Cambridge and Macclesfield.
Its shares had risen around 13% over the previous year, compared with a gain of 43% for Bristol Myers Squibb.
