Man who received experimental pig kidney transplant now has a human organ
By CNN, January 18, 2026One year ago, Tim Andrews was among the world’s first recipients of a genetically modified pig kidney. Now, he is the first in that small group of pioneers to go on to receive a human kidney.
“I’m the first one who went across the bridge. … I’m the only person in the world that’s ever had a pig kidney and then had a human kidney after it,” he told CNN from the hospital on Thursday. “Nobody’s ever been across that bridge. That is cool!”
Andrews, who has diabetes and was living with end-stage kidney disease, received a pig kidney on January 25, 2025, and lived with it for a record 271 days. After his body rejected the organ, it was removed in October, and Andrews returned to dialysis, a gruelling process that kept him alive but made him so miserable it had driven him to the experimental xenotransplant in the first place.
“I cried,” said Andrews, 67. He told his family he didn’t expect to make it through the year.
But at nearly midnight on January 12, Mass General Brigham called to tell him that a human kidney, a near-perfect match, had been identified. He was scheduled for transplant surgery at 8 a.m. the following day.
Andrews now expects to be discharged to his home in New Hampshire on Friday, just days after the milestone organ transplant that made him a living example of the promise of xenotransplantation: Organs from animals may help keep humans alive and healthy enough for a longer-term solution and a new shot at life.
An answer to organ shortages
Xenotransplantation – the transplant of different species’ organs – has been touted as a possible solution to the current shortage of organ donors. The transplanted pig organs are genetically modified to control for rejection and size.
At any given time in the US, more than 100,000 people are waiting for an organ, about 80% of them in need of kidneys. But only the sickest of the sick are listed; just 1 in 8 patients with end-stage renal disease are on the waitlist.
Of the more than 800,000 people with kidney failure, nearly 70% are on dialysis. But dialysis is trying to compress into just a few hours every week the work that the body typically does 24/7. The five-year survival rate for patients on dialysis hovers around.
“Dialysis is not able to reproduce what the body needs in terms of clearing the waste,” said Leonardo Riella, medical director of kidney transplantation at Mass General Brigham Hospital and Andrews’ doctor. “It has a huge burden on the patient, both in their quality of life, but most importantly on their health.”
Andrews was hooked up to a dialysis machine three days a week for up to six hours at a time. Six months after starting dialysis for the first time, he had a heart attack. “It takes a toll on you emotionally and physically; you just get exhausted, and I got sick. I was throwing up all the time,” he said.
Tim Andrews visited his old dialysis center CNN. Sanjay Gupta in the documentary ” Sanjay Gupta Reports: Animal Pharm.” CNN.
While organs remain in short supply, Riella sees xenotransplantation as a solution.
“Even if it is a bridge,” Riella said, “it would be better than [Tim] just staying on dialysis.”
To prepare Andrews for the human transplant, the team at Mass General tested Andrews for new antibodies that could potentially react with the new human kidney and found none. His most recent transplant took just about three hours, and he said his new immunosuppressant regimen is about a third of what he took when he had a pig kidney.
humanity
For Andrews, getting the xenotransplant wasn’t just a matter of hope away from dialysis but hope for patients with end-stage renal disease.
“This will do something for humanity,” he told CNN Chief Medical Correspondent. Sanjay Gupta in the documentary “ Sanjay Gupta Reports: Animal Pharm.”
Immediately following his xenotransplant last year, Andrews felt different. “I was clear. I was not what I call dialysis foggy. I wasn’t tired or anything. All of a sudden I had energy,” he remembered.
But the path forward had ups and downs. Andrews took 52 pills a day to help keep his pig kidney, which he named Wilma, and his immune system in agreement. Ultimately, over the course of nine months, the kidney began showing signs of rejection. He had two infections. Riella said they adjusted Andrews’ immunosuppressant protocol, but the kidneys had become damaged in the process.
“There was some damage to the filters of the kidney that, unfortunately, were not reversible,” Riella said. Ultimately, they removed Wilma, and Andrews had to return to dialysis