The patent cliff for Keytruda is fast approaching in the U.S. Now, as Merck & Co. increasingly looks to life after its oncology megablockbuster, the company is honing its focus on new and upcoming medicines by splitting its core pharmaceutical business in two.
Merck is reorganizing its current human health business into a distinct oncology division and a separate specialty, pharma and infectious diseases unit, the company said in a Feb. 23 release.
The oncology unit will, naturally, oversee Merck’s roster of current and experimental cancer meds, including Keytruda, which Merck has predicted will collect $35 billion in peak annual sales in 2028, the same year the drug will face an expected loss of exclusivity in the U.S. The $31.7 billion Keytruda generated last year made up more than half of Merck’s overall $58.1 billion in pharmaceutical sales in 2025.
Non-cancer products—including newer growth driver Winrevair and aging diabetes stalwart Januvia—will go over to the other unit, which will also oversee Merck’s portfolio of vaccines, according to The Wall Street Journal.
Merck framed the move in terms of strengthening its launch execution, building on recent executive optimism around the drugmaker’s post-Keytruda growth plan. The company aims to “sustain long-term leadership in oncology,” the Keytruda cliff notwithstanding, while deepening its commercial foothold in areas like cardiometabolic medicine and infectious diseases.
With the business split, Merck is elevating new leaders as well.
For the new oncology unit—as well as Merck’s international business—company insider Jannie Oosthuizen has been tapped as executive vice president and president. Oosthuizen is coming over from his role as senior vice president and president of Merck’s U.S. human health business, where he specifically worked on strategy and commercialization for Merck’s products.
Meanwhile, Merck has poached Sanofi veteran Brian Foard to come over as EVP and president of the specialty, pharma and infectious diseases business, with his new post kicking off March 2.
Foard has most recently been with Sanofi as the head of the French pharma’s specialty care business unit, where he helped managed products across immunology, neurology, oncology and rare disease indications. Prior to that, Foard spent nearly 20 years with Swiss dermatology specialist Galderma, Merck said.
Lastly, Merck has slotted Chirfi Guindo, most recently SVP and chief marketing officer at the company, into the role of EVP for strategic access, policy and communications, another executive role.
Post-Keytruda playing field
With Keytruda long ranking as one of the world’s top-selling medicines, all eyes have been on Merck and how the New Jersey drugmaker will navigate the therapy’s impending patent cliff.
But if Merck’s CEO is concerned about the looming sales impact of Keytruda biosimilars, he’s not showing it.
Earlier this month, speaking to analysts during an earnings call, Merck helmsman Robert Davis touted the “broadest and widest pipeline we’ve had in years,” pointing to the potential for more than $70 billion in annual revenue by the middle of the next decade. Davis pinned those ambitions on the strength of new growth drivers, as well as potential upcoming launches brought on board via Merck’s recent acquisitions of biotechs like Verona Pharma and Cidara Therapeutics.
“Our belief in our ability to have substantial growth once we get closer to the [loss of exclusivity] is as high as it’s ever been,” Davis said on the call. “And we’re not done.”
Merck’s overall revenue increased 1% over 2024 last year to hit $65 billion. That sum includes sales from Merck’s animal health business, which is not covered by Monday’s reorganization announcement.
While Keytruda remains Merck’s top seller by a wide margin, several other drugs are coming to the commercial fore, including cancer drug Welireg, which grew sales 37% in the fourth quarter as its international launch gained steam, plus pulmonary arterial hypertension med Winrevair—acquired via Merck’s $11.5 billion buyout of Acceleron in 2021—which broke the blockbuster threshold with sales of $1.4 billion in 2025.
Splitting up a large pharmaceutical business into more focused units, especially along oncology lines, is not an unprecedented move.
Novartis did just that back in 2016, shortly after acquiring GSK’s cancer business, when it set up distinct Novartis Pharmaceuticals and Novartis Oncology divisions. At the time, Paul Hudson—up until very recently the CEO of Sanofi—was tapped to head up the Novartis pharmaceuticals unit.
Meanwhile, Pfizer in 2024 outlined its goals for a new innovative oncology organization following its buyout of Seagen the previous year. The approved cancer meds Pfizer won in that acquisition include Adcetris, Padcev, Tivdak and Tukysa, with the deal at the time doubling the drugmaker’s oncology pipeline to 60 programs.