There are no discussions underway between AstraZeneca and Bristol Myers Squibb over a potential combination, a senior source close to the matter told Reuters.

The source pushes back on days of speculation about a merger that would have created one of the largest pharmaceutical companies in the world.¹

"There is no deal between AstraZeneca and BMS. There never was a deal to be done, and there are no discussions between the companies," the source said, speaking on condition of anonymity.¹

Following the source’s statement, both AstraZeneca and Bristol Myers Squibb declined to comment regarding the denial.¹ A second person familiar with the matter said no talks between the companies were currently active, adding that given the scale of the potential deal, Britain's market abuse rules would have required a public announcement had negotiations been underway.¹

What deal was speculated?

The speculation traces back to August 2, when a person familiar with the situation said AstraZeneca and Bristol Myers Squibb had held preliminary discussions about a possible combination that would create a pharmaceutical company with a combined value of nearly $400 billion.² The Financial Times first reported the talks, but it could not be determined at the time whether they were actually ongoing.² AstraZeneca declined to comment on the report, while Bristol Myers Squibb did not immediately respond to a request for comment.²

How did the market react?

The market’s response to the two reports diverged sharply. Following the initial report of talks on August 2, AstraZeneca shares slid around 9%, the stock's biggest one-day drop since 2020, while Bristol Myers Squibb shares saw little change.¹ The recent denial produced the opposite pattern, with AstraZeneca shares rising 6% on the news, while Bristol Myers Squibb shares fell 2.6%.1

AstraZeneca shareholders have reportedly questioned the strategic logic of such a tie-up, as the company has been one of the sector's most successful under chief executive officer Pascal Soriot's 14-year tenure.

What halted a potential deal?

According to the person familiar with the August 2 report, any combination would have carried significant regulatory risk, with concerns about how U.S. antitrust authorities under President Donald Trump's administration might have assessed it.² The administration has been focused on domestic investment in the sector and expanding U.S. manufacturing.²

A deal would have also marked an unusual structure, with a U.K.-based company acquiring a major U.S. pharmaceutical champion, even as AstraZeneca unveiled plans for a direct U.S. listing to capitalize on stronger valuations in the American market.²

For Bristol Myers Squibb, which has pursued smaller deals to replenish its pipeline as older medicines like Revlimid lose patent protection, a deal would have added scale ahead of possible 2028 patent cliffs for its top sellers Opdivo and Eliquis.²

Sources

1. 'No discussions' over AstraZeneca-Bristol Myers deal, senior source says Reuters August 5, 2026, https://www.reuters.com/world/no-discussions-over-astrazeneca-bristol-myers-deal-senior-source-says-2026-08-05/
2. AstraZeneca held talks with Bristol Myers Squibb on $400 billion megadeal, source says Reuters August 2, 2026, https://www.reuters.com/legal/litigation/astrazeneca-holds-talks-with-bristol-myers-squibb-potential-megadeal-ft-reports-2026-08-02/