There are rumours that a pharma 'mega-merger' – between AstraZeneca and Bristol Myers Squibb – is in the offing, ending several years without this type of deal. A report in the Financial Times suggests that UK-headquartered AZ and BMS of the US have been in discussions for a few months about joining forces to create a $400 billion pharma giant, potentially the fourth-largest by value. The last mega-mergers between big pharma companies were BMS' $74 billion deal with Celgene in 2019 and the $63 billion AbbVie/Allergan tie-up in 2020, and there was a steady stream of large-scale transactions in the previous couple of decades. Since 2020, there have been some big acquisitions, such as Pfizer's $43 billion takeover of Seagen and AZ's absorption of Alexion for $39 billion. On the other hand, BMS shares rose by around the same margin in pre-market trading today.