AstraZeneca rejects Pfizer's take-it-or-leave-it offer

Britain's AstraZeneca on Monday rejected a sweetened and "final" offer from Pfizer, undermining the U.S. drugmaker's plan for a merger to create the world's biggest pharmaceuticals group.

Pfizer had raised its takeover offer to about $118 billion and said it would walk away if AstraZeneca did not accept it, according to Reuters.

Shares in AstraZeneca tumbled 13 percent to 42 pounds by late morning as prospects of a takeover ebbed away. Some major shareholders expressed annoyance at the board's stance.

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