LONDON (AP) — Japanese drugmaker Takeda has reached a tentative agreement to buy Ireland-based Shire Plc for 46 billion pounds ($64 billion) in one of the biggest pharma deals to date.

Takeda has offered the equivalent of 49 pounds in cash and stock for each share of Shire, almost 25 percent more than Tuesday's closing price. Shire said Wednesday that it is prepared to recommend the deal to shareholders, pending agreement on other terms.

Shire says its shareholders would own about 50 percent of the merged company, whose shares will trade in Japan and the United States. Both companies have until May 8 to complete due diligence.

Shire would give Takeda a larger presence in the U.S. and access to the company's expertise in rare diseases, an increasingly important area for pharmaceutical companies.