This story was originally published by WBUR. It was shared as part of the New England News Collaborative.
Tim Andrews leans back in a chair and pulls up the bottom of his t-shirt, revealing a pale pink scar on the right side of his belly. Beneath it sits the kidney of a genetically modified pig that surgeons transplanted into his body six weeks ago.
Dr. Leonardo Riella squirts a cold gel on Andrews’ belly, and presses an ultrasound wand into his skin to check how the kidney is performing. A few bursts of red appear on the screen.
“That’s the blood flow in the kidney,” Riella says. “It’s great.”
The images suggest the kidney is working. Andrews’ vital signs look good, too. His smooth recovery is a source of hope to patients with kidney disease who face long waits for organ transplants. Many die on dialysis treatment each year before they get the chance at surgery.
Andrews is the second patient at Massachusetts General Hospital to undergo this experimental procedure, and one of only two people in the world currently walking around with an organ that came from a pig. Doctors hope this procedure — known as a xenotransplant — soon will be available to many more patients.
Andrews is amazed at how much better he feels. Instead of using a wheelchair, he’s walking on his own again. And he’s smiling.
“I have energy!” he says. “I can't even believe the energy I have. It was like I turned from 66 to 40.”
Before sickness slowed him down, Andrews lived an active life. He worked in supermarkets for three decades, and later as an aide to dementia patients. He enjoyed fishing, hunting and tap dancing.
Two years ago, Andrews was diagnosed with end-stage kidney disease and began dialysis. The treatment kept him alive but made him miserable: too tired to walk, too nauseous to enjoy food.
“I didn’t want to eat, I was throwing up,” Andrews said. “All kinds of bad stuff.”
What he really needed was a kidney transplant. But the wait for a human kidney was seven years. Andrews had to grapple with a stark reality.
“This is it,” he recalls thinking. “I’m going to get weaker and weaker and weaker, and then I’m going to die.”
He was ready to try just about anything to regain some strength and spend more time with his grandchildren. An online search led him to Mass General’s work in the field of pig-to-human organ transplants.
Last March, surgeons at Mass General performed the first-ever pig kidney transplant in a living human, 62-year-old Richard Slayman of Weymouth. Slayman’s recovery began well, but he died of heart problems less than two months later.
Still, Andrews wanted to give it a try. He reasoned that even if the surgery didn’t help him, it could advance the research and help others with kidney disease.
“There’s so many people out there on dialysis, and so many of them are going to die before they even have a choice to get a human kidney,” Andrews said. “So for them, I was like, ‘Let’s just do it.’
“If I die and they learn something, so be it.”
His wife, Karen Andrews, was more hesitant. “I thought, ‘Oh boy, I don't know. We need to talk about this more.’ But he was just so excited about it,” she said.
Her husband convinced her and his doctors that he was ready. He started exercising at the gym and lost weight to prepare for the operation.
A Cambridge-based biotech company called eGenesis has been experimenting with Yucatan minipigs, editing their genetic makeup to make their organs safer and more compatible with humans.
On Jan. 25, surgeons from Mass General drove to a facility an hour away to procure a kidney from one of those genetically modified pigs. They brought it back to the hospital on ice, and during a two-and-a-half-hour surgery, attached it to the blood vessels inside Andrews’ abdomen.
Within two minutes, the kidney started making urine, just like a healthy human organ.
“That's the most critical step of the whole surgery,” said Riella, Mass General’s medical director of kidney transplantation. “Right away, his kidneys were doing the best we could expect.”
Andrews is one of only four people in the world who have ever received pig kidneys. And he’s one of just two still living. The other is Towana Looney, an Alabama woman who received a pig kidney transplant at NYU Langone Health in November.
Andrews said he called Looney before his surgery. “He can say scientifically what’s going to happen,” Andrews said, gesturing toward his doctor, “but she’s got one in her.”
Work in the field of xenotransplantation is moving fast, although it has critics who raise questions about the ethics of raising animals for organs, and the risk of spreading diseases to humans.
Mass General is planning two more pig-to-human kidney transplants this year, as part of a federally approved study. Several other hospitals and private companies are also working to solve the human organ shortage through xenotransplants.
“We want to learn as much as we can,” Riella said. “If there are things that we need to adjust or change, we'll do that. And we hope that in a few years, it will be a treatment that we can consider for patients who don't have an option of a human kidney in a timely fashion.”
Andrews makes the 70-mile trip from his home in Concord, N.H., to the transplant clinic at Mass General twice a week, so doctors can monitor his recovery. They check his blood pressure, listen to his breathing, adjust his medications and study his urine.
They don’t know how long his new kidney will last. Experiments in monkeys suggest at least two years. But Andrews — who turns 67 this month — is making plans for the future. He wants to get back to fishing and tap dancing, walking his dog and playing with his grandkids.
“ I've seen more life in him in the past month than I have in the last two-and-a-half years,” his wife said.
Next year, if doctors give the go-ahead, Andrews would like to take her to Italy.
“We’ve always talked about it but never done it,” he said. “And now I’m in the mode of: Let’s do it now, while there’s time.”
This segment aired on March 7, 2025.
