AstraZeneca shares have jumped 15 percent in early trading after U.S. pharmaceutical firm Pfizer publicly disclosed details of a $100 billion bid approach.
Pfizer, the maker of Viagra, said Monday that AstraZeneca rejected an initial approach in January valuing the company at about 59 billion pounds ($100 billion). The cash and shares deal would represent a 30 percent premium on AstraZeneca's closing share price of 35.26 pounds on Jan. 3, the date of the offer.
Pfizer remains interested and is confident a combination is possible.
The deal comes as drugmakers take advantage of easier financing in a spate of mergers and acquisitions. Swiss drugmaker Novartis AG last week traded its vaccine business for GlaxoSmithKline Plc's cancer drug business and sold its veterinary drug business to Eli Lilly and Co.