While both drugmakers face looming patent cliffs, analysts say joining forces could help Bristol Myers Squibb replenish its eroding portfolio—while the strategic case for AstraZeneca seems to be more mixed.
As rumors swirl about a potential Bristol Myers Squibb/AstraZeneca mega-merger, analysts say such a deal could help BMS in particular offset looming portfolio erosion.
Over the weekend, The Financial Times reported that Big Pharmas BMS and AstraZeneca—each worth more than $130 billion—are in discussions about a possible merger. If it comes to pass, it would be the largest in the industry’s history.
Patent cliffs may explain some of the reasoning behind a potential transaction.
“Both companies face meaningful loss of exclusivity for key brands by 2030, totaling to roughly $50 billion of revenue reported in 2025,” analysts at William Blair wrote in a Monday note. “This would place additional emphasis on operational synergies between the two companies to justify the transaction.”
Though both organizations are experiencing and face upcoming patent expirations, BMS in particular is entering “a difficult period of revenue headwinds from loss of exclusivity for several products,” William Blair wrote. In addition to ongoing patent losses for CTLA-4 inhibitor Yervoy and multiple myeloma treatment Revlimid, the pharma is also staring down impending exclusivity losses for two of its top-selling drugs: Pfizer-partnered blood thinner Eliquis and PD-1 checkpoint inhibitor Opdivo. Both patent losses are expected to take effect in the U.S. in 2028.
Last year, Eliquis brought in $14.4 billion in global sales, while Opdivo secured $10 billion in worldwide revenue—together accounting for half of BMS’ entire $48.2 billion revenue. Leerink Partners in a Monday note projected total BMS revenues of $38.7 billion in 2030.
“Additional bolt-on acquisitions may prove difficult to offset the decline of legacy products,” William Blair wrote. “Therefore, a large strategic merger could offer a near-term opportunity for value creation for shareholders.”
But the patent cliffs also muddy the rationale behind a merger.
“We believe the strategic and financial rationale is mixed, especially for AZN, given the company’s strong pipeline and organic growth outlook,” Leerink wrote. While a merger with BMS could boost U.K. pharma AstraZeneca’s exposure in the U.S., the analysts said, the 2028 patent cliffs “raise questions around whether a transaction would improve AZN’s long-term growth profile.”
When news first broke over the weekend of merger chats, analysts largely brushed off the idea as “unlikely,” citing the fact that the companies have competing products that would greatly complicate an antitrust review. William Blair believes a transaction could require divestitures, particularly given overlap between AstraZeneca’s Imfinzi and BMS’ Opdivo. Beyond the high scrutiny the overlapping immunotherapy profile would face, the pharma’s marketed portfolios are mostly complementary instead of overlapping, Leerink said.
Leerink also looked to several key clinical catalysts coming up this year and next that “could introduce volatility” for AstraZeneca if unsuccessful.
These readouts include Phase 3 data for several BMS drugs: admilparant in idiopathic pulmonary fibrosis in 2026, milvexian in atrial fibrillation expected early next year, and Cobenfy in Alzheimer’s disease psychosis, now expected in 2027 after being previously delayed.
“It is interesting that merger talks are happening now, ahead of major pivotal readouts,” Leerink analysts mused in a separate note on Sunday.
AstraZeneca also has high-profile Phase 3 readouts coming up, including for its TROP-2 antibody-drug conjugate datopotamab deruxtecan (Dato-DXd), marketed as Datroway. A transaction could provide a meaningful cushion for the company if readouts disappoint, especially as AstraZeneca aims for $80 billion in revenue by 2030, Leerink wrote. The analysts currently model the company narrowly cresting that goal at $79.8 billion.
As of market close on Monday, AstraZeneca’s shares fell about 7% to $157.97, while BMS was flat on the news at $65.47.
