AstraZeneca and Bristol Myers Squibb have reportedly held discussions about a possible merger that could value the combined pharmaceutical company at approximately $400 billion. According to the Financial Times, talks have taken place over several months, although there is no certainty that an agreement will be reached. If completed, the transaction would rank among the largest corporate mergers on record.
The potential combination would bring together two major drugmakers with significant cancer-treatment portfolios. Bristol Myers expanded its position in oncology through a series of acquisitions beginning in 2007, including its 2009 purchase of Medarex. That deal added an experimental treatment for metastatic melanoma that was also being studied for possible use against lung and prostate cancers. Bristol Myers also marketed established cancer medicines for colorectal, head and neck, breast, and other cancers.
AstraZeneca has likewise made oncology a central part of its business. The company reported that cancer treatments generated about $25 billion in 2025, representing nearly half of total sales. Cardiovascular, renal, and metabolism medicines contributed approximately $12 billion. Recent second-quarter results also indicated continued demand for the company’s cancer and rare-disease products.
The reported discussions come as AstraZeneca seeks a stronger presence in U.S. capital markets while retaining its London listing. Under Chief Executive Pascal Soriot, the company’s share price has risen substantially over 14 years, outperforming the broader FTSE 100 and British competitor GSK. AstraZeneca previously rejected a takeover approach from Pfizer about 12 years ago.
Neither company immediately commented on the report. Any merger would likely face detailed scrutiny from investors, regulators, employees, and health-care customers because of its size and the overlap between the companies’ operations. For now, the discussions remain preliminary, and the eventual structure, timing, financing, and regulatory prospects of a transaction have not been publicly established. No formal proposal has been announced.