AstraZeneca shares fall 8.9% over merger talks with US cancer drug firm

$400bn tie-up with Bristol Myers Squibb would create world's fourth largest drugmaker but analysts question rationale for deal

More than 17bn was wiped off the value of Britain's biggest drugmaker, AstraZeneca, on Monday after a report that it was in discussions to take over its US rival Bristol Myers Squibb in a deal that would create a near $400bn (300bn) pharmaceutical group.

AstraZeneca, run by Pascal Soriot, its longtime chief executive, had been worth nearly 196bn before the news broke. BMS, headquartered in Princeton, New Jersey, and known for its cancer treatments, was worth $133bn (98bn).