United Therapeutics opens its third facility for organ donor pigs in Houston

United Therapeutics opens its third facility for organ donor pigs in Houston

On 20 October, United Therapeutics announced the opening of a facility named after surgeons Bartley Griffith and Robert Montgomery. Its first facility, in Virginia, has operated since 2024 to supply organs for clinical trials. The second opened in Minnesota on 12 August. The Minnesota and Houston facilities are designed for commercial organ production following FDA approval.

The Houston facility will house gene-edited pigs whose kidneys and hearts the company is developing for transplantation into humans. Transplant recipients receive drugs to suppress their immune systems, which means normally harmless pig microbes can become dangerous to them. DNA from a latent virus, porcine cytomegalovirus, was found in the pig heart that Griffith transplanted into a human in 2022, the first such transplant in the world. The authors of an analysis of the case, including Griffith, suggest that viral reactivation may have triggered inflammation that damaged the heart.

Keeping organs free of such viruses requires a “designated pathogen-free” facility: the herd must be free of pathogens on a predefined list. Air, water and feed are filtered, and entry is through decontamination airlocks. At an investor conference on 23 September, company head Martine Rothblatt said of these facilities: “It is the same as GMP, but for pigs.” GMP stands for good manufacturing practice, a standard for pharmaceutical production. In its annual report, the company says it expects the Virginia facility to supply organs produced to this standard for clinical trials.

The quarterly report describes the Virginia facility as “first of its kind”: an unforeseen disruption or a disease outbreak in the herd could substantially delay organ development. The Virginia facility has a target capacity of up to 125 organs per year. In 2025, 28 378 kidneys were transplanted in the United States. The other two facilities were built to reduce the risk of such disruptions and increase capacity. According to the annual report, the three facilities are intended to provide the initial commercial supply, while meeting total demand will probably require additional facilities.

The Texas construction project registry lists an estimated cost of $96 million for the Houston facility, while the Minnesota facility cost $110 million, according to the Post Bulletin newspaper. Speaking at the same conference, the chief financial officer said the company had previously considered facilities costing $1,5–2 billion. It is now building three smaller facilities and, he added, will be able to invest in them as the trials progress.

The EXPAND trial, in which people with kidney failure receive pig kidneys, sets the milestones. The company announced the first transplant on 3 November 2025: Montgomery performed the procedure at New York University’s medical center. By 23 September, four patients had received kidneys, and two more were scheduled for surgery this year. Three months after the sixth transplant, data from all six patients will be submitted to the FDA. If the agency finds the results satisfactory, the trial will expand to enroll patients for a license application. Rothblatt expects commercial sales to begin no later than 2030.

According to the medical center, in September 2021 Montgomery performed the world’s first transplant of a gene-edited pig kidney into a person who had been declared brain-dead. He has lived with a donor heart himself since 2018, after four consecutive cardiac arrests. Following his own transplant, he came to see previous efforts to find suitable organs, such as kidney exchanges between incompatible donor-recipient pairs, as insufficient. He described them to The New York Times as:

“…just rearranging deck chairs on the Titanic.” “This will never be enough to provide organs for people whose organs are failing.”