A gene-edited pig organ kept a New Hampshire man off the treatment that did the work of his failed organs for 271 days before he received a human organ transplant, doctors reported in a study published in The Lancet. The patient, Tim Andrews, was 66 at the time. His own organs had failed completely, and he had no living donor available. Researchers at Mass General Brigham led the study.
What Happened to Tim Andrews
Andrews received the pig organ in January 2025. The organ came from a pig with 69 gene edits meant to help the human body accept it, according to Euronews. The organ supported him without the need for that treatment for 271 days.
Andrews had been placed on a list to wait for an organ from a person who had died. Euronews reported that the expected wait was over five years. In January 2026, doctors removed the pig organ, and Andrews received a human organ. He is now 68.
NPR reported that Andrews’ own organs had stopped working, and that despite treatment, doctors told him he would probably die before he could get a transplant. He said he decided to take part in the study even so.
“If I can do something for humanity on my way out, why not?” he told NPR.
Andrews told NBC News he now believes he could have decades ahead of him. He said that when he first discussed the use of animal organs in humans with his doctor, Dr. Leonardo Riella, he was told such treatment would likely not be ready for at least ten more years.
The Second Patient: Bill Stewart
Andrews was not the only patient in the study. eGenesis, a company based in Cambridge, Massachusetts, made the pig used for the transplant. On Thursday evening, the company said two of its first patients to receive gene-edited pig organs have now successfully received organs from human donors, STAT News reported.
The second patient was named later as Bill Stewart. He had been kept without his name given in some early reports. Stewart had problems during his time with the pig organ, including swelling and a low red blood count, according to the Boston Globe, citing STAT.
eGenesis CEO Mike Curtis said that when Stewart went back to treatment after nine months with the pig organ, he was much healthier than when he had first come off treatment nine months earlier. Curtis said this suggested the pig organ gave him a real benefit, even though it was later removed.
Comparing the Two Cases
| Detail | Tim Andrews | Bill Stewart |
|---|---|---|
| Pig organ received | January 2025 | Not stated |
| Time without treatment | 271 days | About nine months |
| Problems reported | Not stated | Swelling, low red blood count |
| Result | Received human organ in January 2026 | Returned to treatment, later received human organ |
What Doctors Are Saying
Dr. Muhammad Mohiuddin of the University of Maryland studies the use of animal organs in humans. He was not involved in the study. He called the results encouraging. NPR reported that he said the immediate need is to give patients enough time alive to get a chance at a human organ.
STAT News reported that in both cases, doctors removed the pig organ, and the patient went back to treatment for months before a human organ became available. STAT News also reported that both patients went most of a year without needing that treatment.
What This Does and Does Not Show
The results point to a few clear things and some open questions.
- A gene-edited pig organ can support a human patient without regular treatment for many months — 271 days for Andrews, about nine months for Stewart.
- Both pig organs were eventually removed, and both patients needed treatment again before they got a human organ.
- The pig organ may have improved Stewart’s health, based on Curtis’s comparison of his state before and after the nine months, though this is one case, not a large study.
The list continues with two more points about the limits of what has been shown so far.
- Problems did occur, including swelling and a low red blood count in Stewart’s case, showing the approach carries risk.
- Neither case shows that a pig organ can stand in for a human organ over time. Both were used as a bridge to a human transplant.
The study does not show how this approach would work across many more patients. It also does not show how safe it is over a longer period of time.
Both patients needed a human donor organ in the end.
Why the Wait Time Mattered
Andrews faced an expected wait of over five years for an organ from a person who had died, according to Euronews. The pig organ gave him time without treatment during that wait. It did not remove his need for a human donor organ.
Mohiuddin’s comment to NPR reflects that point. The current goal is giving patients more time alive, so they have a better chance of reaching a human transplant rather than avoiding one altogether.
The Lancet study, along with reporting from NBC News, NPR, STAT News, Euronews, VINnews and the Boston Globe, documents two patient cases. None of these reports claim the treatment is ready for wide use.
For Andrews, the experience changed what he expects for himself. He told NBC News he now believes he could have decades ahead of him — a change from what he says Dr. Leonardo Riella once told him, that such treatment might not be ready for at least ten more years.