AstraZeneca is in discussions to take over its US rival Bristol Myers Squibb in a deal that would create a pharmaceutical group worth close to $400 billion (approximately £300 billion), ranking among the largest transactions in the industry’s history.
Britain’s biggest drugmaker, led by longtime chief executive Pascal Soriot, is the second-largest listed company in the UK, with a market value of nearly £196 billion before news of the talks emerged. Bristol Myers Squibb, headquartered in Princeton, New Jersey, and known for its portfolio of cancer treatments, carries a market capitalisation of about $133 billion.
A completed tie-up would produce the world’s fourth-largest drugmaker, combining AstraZeneca’s oncology and respiratory franchises with Bristol Myers Squibb’s established cancer and immunology treatments.
The prospect has drawn a cautious response from parts of AstraZeneca’s shareholder base. Some investors have questioned the scale and cost of the transaction, wary of the integration risks that accompany deals of this magnitude and the pressure such an acquisition could place on the acquirer’s balance sheet.
Large pharmaceutical mergers have historically been driven by the need to replenish drug pipelines and offset revenue lost when blockbuster medicines face patent expiry and generic competition. Bristol Myers Squibb has been navigating exactly that challenge, with several of its top-selling products approaching the end of their exclusivity periods.
The company has continued to post solid financial results in recent quarters, even as it invests to renew its product lineup. AstraZeneca, meanwhile, has expanded aggressively across oncology and rare diseases, positioning itself as one of the sector’s most acquisitive players.
This development comes as major drugmakers race to secure next-generation therapies, particularly in cancer treatment, where competition for advanced platforms has intensified. Consolidation has accelerated across the industry as firms seek scale to fund costly research programmes.
Neither company has confirmed the terms, timing or structure of any potential agreement, and there is no certainty the discussions will result in a transaction. A deal of this size would also face close scrutiny from antitrust regulators in multiple jurisdictions, given the combined group’s dominant position in several therapeutic areas.
The talks are expected to test investor appetite for mega-mergers at a moment of heightened uncertainty over drug pricing policy and reimbursement in key markets. Further details are anticipated as negotiations progress.