A kidney transplanted from a pig has functioned inside a patient for 271 days, which US doctors state is the longest on record. The patient, Tim Andrews, said the transplant offered him "hope" and allowed him to avoid months of dialysis.
The team at Mass General Brigham hospital suggests their work demonstrates that pig organs could be used as a temporary solution until a human transplant becomes available. Mr Andrews, who was 66 when he received the xenotransplant on January 25, 2025, had end-stage kidney disease due to type 2 diabetes.
The pig organ eventually failed and was removed in October 2025, leading to a short period of dialysis before a human donor was found in January 2026. Doctors and scientists are exploring xenotransplantation, the use of organs from other species, to address the shortage of organs for transplants.
Pigs are considered suitable for xenotransplantation due to their organ size and extensive farming experience. Researchers have developed Yucatan miniature pigs with 69 genomic modifications to 'humanise' their organs, aiming to prevent the human immune system from rejecting them.