Merck plans to move manufacturing of its biggest drug, Keytruda, to a new U.S. factory and lab in Delaware
With $30 million in state grants, the pharmaceutical giant is building a factory to employ 500 at an old DuPont site near Wilmington.
Merck, the New Jersey-based drug giant, is spending $1 billion on a new Delaware factory to bring production of its best-selling cancer drug Keytruda to the U.S. and speed future drugs to market.
Keytruda is currently made in Ireland and by contract manufacturers in the United States. President Donald Trump has complained about Ireland acting as a low-cost drug factory center and tax haven at the expense of U.S. workers and tax collections.
The new Merck complex in Wilmington will be a “cornerstone of our biotech future,” chief executive Robert M. Davis said at a groundbreaking Tuesday on the former DuPont Co. chemical and office campus. It will be “the future U.S. home for producing Keytruda for U.S. patients.”
Though manufacturing will be automated with robotics and artificial intelligence software, Davis said Merck would create 500 new jobs in advanced manufacturing and research and development at the site by the time construction is complete in five years, and potentially thousands more drug development jobs long-term.
“This is a significantly new era in drug development,” said Sanat Chattopadhyay, president of the company’s manufacturing division. Producing bio-based and complex therapies in the United States for the U.S. market “means we will be able to speed access to patients much faster.”
Merck officials said the site was chosen over rival locations in Pennsylvania, Maryland, North Carolina, Massachusetts, and other states where Merck has facilities. Delaware officials earlier this year approved grants of up to $30 million for the project to help attract Merck.
The company is among the larger employers in the Philadelphia area, with around 14,700 staff spread across its Upper Gwynedd Township offices, West Point manufacturing plants, and Spring House research labs, all in Montgomery County, and other area sites.
Merck plans to complete labs at the former DuPont Co. Chestnut Run research and production site at 984 Centre Rd. in Wilmington by 2028 and add manufacturing and offices by 2030.
Delaware’s gain isn’t Pennsylvania’s loss, said Mike Wojewodka, president of developer MRA Group, which has also built biotech centers at former industrial sites in Philadelphia and Montgomery County. He said both states are among those competing for biotech facilities, and both benefit from large regional employers expanding, no matter where the facilities are.
Speaking at the groundbreaking, both Gov. Matt Meyer and New Castle County Executive Marcus Henry smilingly urged employees from Merck’s Rahway, N.J., headquarters to move their homes to Delaware, which has fewer layers of municipal government and strong state funding for public schools that keep property taxes lower than in the Garden State.
Merck will deploy robots, artificial intelligence software, and other new technologies at the Wilmington location.
Among its goals: to develop subcutaneous drug delivery (injection directly into fatty tissue below the skin) for Keytruda, produce antibody-drug conjugates that combine biological disease-fighting cells with chemotherapy drugs, and streamline production to speed new products to patients faster than older plants, Chattopadhyay said.
MRA, with initial funding from Fulton Bank, bought the former DuPont complex for $40 million in 2021 as DuPont CEO Edward Breen sold and spun off a series of business units. At its peak in the 1970s, DuPont and its chemical and materials businesses employed more than 30,000 Delaware residents and dominated the state economically. It currently employs around 2,500.
The developer has leveled old buildings and is overseeing pollution remediation at the site.
The new Merck factory is under construction alongside a rising Marriott Residence Inn, and a childcare center for workers’ families, among other amenities.
Other tenants at the complex include DuPont; chemical maker Celanese, which operates a former DuPont business; and Delaware-based biotech companies Solenis and Prelude. Prelude is a spinoff of another Delaware-based biotech company, publicly traded, Wilmington-based Incyte, the largest drug company founded in the Philadelphia area since the 1990s.
The new plant is underway at a time when Philadelphia area biotech and bio manufacturing development has slumped following an investment boom in the late 2010s.
MRA’s other biotech projects include sites in Spring House, near Merck’s labs; University City near the University of Pennsylvania and Veterans Administration hospitals; and at Pennovation, Penn’s engineering and business center at the former DuPont paint factory in South Philadelphia.
Merck in March told workers that it plans to close one of its smaller Pennsylvania facilities this summer — the Cherokee plant in Northumberland County, idling 163 workers.