By_Suraj Karowa
October 29, 2025
– In a bittersweet milestone for xenotransplantation,67 Year-old Tim Andrews of New Hampshire had his genetically modified pig kidney removed after functioning for a record 271 days. Surgeons at Mass General Brigham in Boston performed the explant on Thursday due to declining organ function, forcing Andrews back to dialysis. The procedure marks the longest survival yet for a living human with a pig kidney, but underscores persistent challenges in bridging animal organs to human bodies.
Andrews, who has battled diabetes since the 1990s and end-stage kidney disease for three years, received the transplant in January as the fourth U.S. patient in such trials. The kidney, sourced from a pig named “Wilma” and edited with 69 genetic modifications by eGenesis to reduce rejection risks, initially transformed his life. “I was alive, and I hadn’t been in a long time,” Andrews told CNN’s Dr. Sanjay Gupta in the documentary Dr. Sanjay Gupta Reports: Animal Pharm.
Freed from six-hour dialysis sessions three days a week, he cooked meals, vacuumed his home, walked his dog Cupcake, and even threw the ceremonial first pitch at Fenway Park in June, cheering the Boston Red Sox.
Yet, complications arose. Andrews cited “experimental drugs with unexpected side effects” in a Facebook post Saturday, describing the journey as “punishing” but proud.
He hailed Wilma as “my hero” and a “warrior” for navigating “bumps in the road.” Mass General Brigham praised him as a “selfless medical pioneer,” while Gupta called his positivity “unwavering” and his participation vital for future patients.
Nearly 90,000 Americans await kidney transplants, per the Organ Donor Foundation, with over 170 million registered donors falling short. Xenotransplants aim to alleviate this shortage, but outcomes remain mixed.
Prior Cases Highlight Risks
Richard Slayman (March 2024): First U.S. pig kidney recipient at Massachusetts General Hospital. Died two months later from unrelated causes.
Lisa Pisano (April 2024): Received pig kidney plus mechanical heart pump at NYU. Organ failed due to poor blood flow; removed after one month. Died in July 2024.
Towana Looney (November 2024): NYU patient; kidney lasted four months and nine days before immune rejection prompted removal in April 2025.
Bill Stewart (June 2025): Massachusetts General Hospital transplant. Functioned well initially; the patient returned to work but reported suboptimal energy by September.
Mass General Brigham plans another pig-to-human kidney transplant later this year, signaling ongoing commitment despite hurdles.
Scientific and Ethical Context
Xenotransplantation has advanced rapidly with CRISPR gene editing, targeting issues like alpha-gal syndrome (where human antibodies attack pig sugars) and viral risks. The FDA oversees these under compassionate use protocols. Proponents argue pigs’ anatomical similarities and rapid breeding make them ideal donors, potentially saving thousands annually. Critics worry about zoonotic diseases, ethical animal use, and long-term rejection—evident in Andrews’ case, where function waned without acute rejection details released.
Andrews remains on the human kidney waitlist. His experience, while ending in removal, provides critical data on immunosuppression, infection control, and organ viability. “I am proud of everything we discovered,” he wrote, urging others: “Donate a Kidney and be a HERO!”
In related news, former New York Jets star Nick Mangold died at 41 from kidney disease complications, highlighting the urgency. As trials continue, Andrews’ story embodies hope tempered by reality in the quest to end dialysis dependency.