AstraZeneca shares fell as much as 7% in early London trading, last down 6.2%, after the Financial Times reported months-long merger talks with Bristol Myers Squibb.
The potential tie-up would combine a $264 billion AstraZeneca with a roughly $133 billion Bristol Myers, creating one of the biggest pharmaceutical deals ever at about $400 billion.
Details remain scarce, and FT sources said a deal may still fail; AstraZeneca declined to comment and Bristol Myers did not immediately respond outside normal working hours.
Jefferies analysts said they were "a bit perplexed" by the report, arguing AstraZeneca's strong growth and innovation profile means it does not need financial engineering.
The talks surfaced as AstraZeneca, led by CEO Pascal Soriot since 2012, targets $80 billion in 2030 sales after reporting $58.7 billion last year.
What hidden pipeline asset makes Bristol Myers Squibb so valuable that AstraZeneca is willing to risk severe investor backlash in 2026?
Why would a thriving AstraZeneca risk its ambitious growth goals to absorb Bristol Myers Squibb and its massive patent cliff?
AstraZeneca’s $400 Billion Bid for BMS: Patent Cliffs, Oncology Overlap, and the Global Pharma Shakeup
Overview
In August 2026, news broke that AstraZeneca and Bristol Myers Squibb (BMS) were in early merger talks, sparking a sharp split in market reactions: AstraZeneca’s shares plunged while BMS’s rose. This reflected investor doubts about AstraZeneca taking on BMS’s looming patent cliffs and declining revenues, even as AstraZeneca aimed for ambitious growth targets. The proposed merger faces tough regulatory scrutiny due to overlapping cancer drug portfolios, with authorities likely to demand major divestitures. Both companies have histories of large layoffs and R&D site closures during restructuring, raising concerns about job losses and innovation. Meanwhile, AstraZeneca’s shift toward US investment and stock listing has fueled political anxieties in the UK about losing a national champion.