AstraZeneca holds talks with Bristol Myers Squibb over $400bn tie-up

A potential AstraZeneca-Bristol Myers deal worth $400 billion would create one of the world’s largest drugmakers and combine major cancer franchises.

AstraZeneca declined to comment, while Bristol Myers Squibb did not immediately respond to CNBC's request for comment outside normal U.S. business hours.

The United Kingdom's second-most valuable listed company, pharmaceutical firm AstraZeneca, has been revealed to have been holding talks for some time with United States-based rival Bristol Myers Squibb, or BMS, about a merger, which could result in a global pharma giant worth nearly $400 billion.

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