Key facts
- AstraZeneca shares declined 6% to 11,866p.
- The company is reportedly exploring a $400 billion merger with Bristol Myers Squibb.
- Investors have expressed skepticism and potential opposition to the deal.
- Concerns exist regarding the deal's impact on AstraZeneca's UK base and London listing.
- Antitrust issues are expected due to overlapping oncology portfolios.
AstraZeneca's share price experienced a significant drop of six percent in early trading, falling to 11,866p, following reports that the company is considering a potential $400 billion merger with its U.S. counterpart, Bristol Myers Squibb. This potential 'megadeal' has been under discussion between the two pharmaceutical giants in recent months, according to the Financial Times.
Unlike typical FTSE takeovers that often lead to share price spikes, AstraZeneca's initial market reaction suggests investor apprehension. Richard Hunter, head of markets at Interactive Investor, noted this sentiment indicates potential opposition to such a deal, questioning why AstraZeneca would pursue M&A when it has a strong pipeline capable of independent growth until 2030. Hunter also highlighted concerns over the deal's implications for AstraZeneca's UK ties, especially as CEO Pascal Soriot has previously described the company as "very American" and it operates numerous sites across 11 U.S. states. The company's upgraded listing on the New York Stock Exchange last September and a $50 billion investment deal with the Trump administration further underscore its U.S. pivot, despite assurances of maintaining its Cambridge base and London listing, including a recent pledge of £300 million into UK operations.
Russ Mould, investment director at AJ Bell, commented that the speculated merger could have repercussions beyond the pharmaceutical sector, potentially shifting AstraZeneca's 'centre of gravity' across the Atlantic and diminishing the UK stock market's value. The sheer scale of the $400 billion valuation also surpasses previous large transactions, such as the 2000 merger of Vodafone and Mannesmann. Mould cautioned that such major transactions often face integration challenges and substantial antitrust scrutiny, particularly in the U.S., given both companies' significant and overlapping focus on oncology treatments. Cancer drugs represented approximately $25 billion of AstraZeneca's 2025 sales, and over 40 percent of Bristol Myers Squibb's revenue in the first half of 2026.