New York, June 4, 2026, 17:05 (EDT)
Merck & Co. shares climbed 4.9% to $120.26 late Thursday, adding $5.59 and putting the drugmaker among the top movers in a Dow rally paced by healthcare stocks. UnitedHealth and Merck made up about a third of the Dow’s gains earlier in the day, MarketWatch said.
Merck is still defined by how quickly it can find a follow-up to Keytruda. The blockbuster cancer drug brought in over $30 billion in 2025, nearly half of Merck’s sales. U.S. exclusivity for Keytruda runs out in 2028, when generics could hit.
Merck left the American Society of Clinical Oncology meeting this week and moved into investor events with a clearer message. The company said Keytruda is still holding up, and its next group of oncology drugs is moving beyond the slide deck. That is why this week’s cancer meeting had more impact than a usual conference stop.
Merck’s head of late-stage oncology clinical development, Marjorie Green, called ASCO “an exciting time for Merck” at the Jefferies Global Healthcare Conference on Thursday. She highlighted new OptiTROP-Lung05 results for sacituzumab tirumotecan, or sac-TMT, with Keytruda. Green said the data showed a clinically meaningful gain in progression-free survival, though overall-survival numbers are still early. Seeking Alpha
Merck repeated its pitch during its June 1 ASCO investor event. Dean Li, who heads Merck Research Laboratories, said Keytruda has 44 FDA approvals in 19 tumors and two tumor-agnostic categories. He also pointed to around 60 Phase 3 oncology studies underway, with 40 focused on new pipeline drugs. Li said Merck is targeting a “steady stream or cadence” of significant data releases. Q4 Solutions
Keytruda holds its lead after Akeso/Summit’s ivonescimab cut the risk of death by 34% in a Phase 3 lung-cancer trial in China, but investors weren’t convinced the result would carry over to the U.S. or global markets. BMO Capital Markets analyst Evan David Seigerman wrote, “King Keytruda’s reign continues,” and called ivonescimab “hardly the competitive threat” that was expected. MarketWatch
PD-1/VEGF drugs, which hit both immune brakes and blood supply to tumors, are still in play. BMO told BioSpace that the HARMONi-6 data likely came from patients who aren’t typical, so it’s unclear if the benefit is broad. Bristol Myers Squibb and BioNTech have pumitamig in the works too, keeping investor focus on the space.
Merck is pushing sac-TMT, an antibody-drug conjugate, or ADC, as its answer. ADCs use an antibody to deliver a toxic payload to tumor cells. Sac-TMT is in the TroFuse development program, which the company says covers early to late-stage disease in more than nine disease areas and over 15,000 patients globally.
Shweta Jain, an oncology executive at Merck, told BioPharma Dive the company sees sac-TMT as “one of our cornerstone ADCs,” adding that new data give Merck “increasing level of confidence” as the global studies keep going. Gilead’s Trodelvy and AstraZeneca and Daiichi Sankyo’s Datroway are the main competition in TROP2-directed ADCs, but the first-line lung-cancer space is still open. BioPharma Dive
Merck’s stock is up, but the finances are mixed. In April, Merck reported a 5% gain in first-quarter sales to $16.3 billion. Sales for Keytruda/Keytruda Qlex jumped 12% to $8.03 billion, while Gardasil vaccine sales dropped 19%. The company lifted the midpoint of its 2026 sales outlook to $65.8 billion-$67.0 billion. CEO Robert Davis said Merck was “moving with speed to transform our portfolio.” The quarter included a $3.62-per-share charge tied to the Cidara buy. Merck.com
But Thursday’s move could prove too optimistic. China cancer data may not hold up in broader global studies, and regulators could press harder on safety or survival. Any delay in fresh approvals would leave Keytruda doing more of the work right as biosimilars appear. Gardasil weakness and pricing pressure would just add to the squeeze.
Up next is June 9, when CEO Robert Davis and R&D head Dean Li are slated to talk at Goldman Sachs’ global healthcare conference. Investors aren’t expecting more talk of a broad pipeline. They want specifics—what assets could convert trial success into approvals, reimbursement, and sales before Keytruda’s patent cliff.
MRK is rallying for now, but it’s relief, not a full rerating yet. The future here hinges on Merck turning its pipeline into clear earnings, not just showing big science.