A pig kidney bridged a patient to a human transplant

Massachusetts General Hospital, part of Mass General Brigham, published a first-in-human study in The Lancet on 3 September 2026 arguing that a pig kidney can serve as a bridge rather than a destination. The patient, Tim Andrews, received a gene-edited pig kidney in January 2025 and lived 271 days without dialysis — the longest recorded dialysis-free survival after a porcine kidney xenotransplant in a living person.

In January 2026 he received a deceased-donor human kidney. The paper reports immediate graft function and no evidence of sensitisation during follow-up, which is the result that matters for the bridge argument: a xenograft that leaves the immune system primed against human tissue would cost the patient the transplant they were waiting for.

The framing is a shift. Xenotransplantation has been pursued as a replacement for the donor shortage, and every previous attempt was measured by how long the animal organ lasted. This one is measured by what happened next. The paper is titled “Porcine kidney xenotransplantation as a bridge to allotransplantation: a first-in-human study” (DOI 10.1016/S0140-6736(26)01295-X). It is one patient, and the authors present it as a case, not a trial.