A Transplanted Pig Kidney Buys Time for a Human One (Economist)

note Partial capture The raw file holds only the article's opening paragraph. The case it describes — Tim Andrews, Massachusetts General Hospital — is documented in a Lancet case report and a Mass General Brigham release (https://news.massgeneralbrigham.org/en/pig-kidney-xenotransplant-bridge-to-human-transplant), which supply the detail below. Anything beyond the lede is from those sources, not the Economist's text.

Summary

The Economist's framing: a gene-edited pig kidney was used for the first time as a stop-gap — a bridge to keep a patient alive and off dialysis until a human kidney became available — rather than as a last-ditch end in itself. Tim Andrews, 66, with end-stage renal failure and declining health despite dialysis, received the pig kidney in January 2025 and a deceased-donor human kidney in January 2026.

Key facts (Lancet report via MGB release)

• Pig kidney: transplanted January 2025 at Massachusetts General Hospital under an FDA Expanded Access IND; organ from a CRISPR-edited pig supplied by eGenesis (Cambridge, MA). Function was immediate; Andrews left hospital within a week, off dialysis for the first time in over two years.
• Duration: 271 days dialysis-free — the longest reported for a living recipient of a pig kidney at the time. (MGH's first living-recipient pig kidney, 2024, lasted 52 days before the patient died of unrelated cardiac causes.)
• Why it failed: about six months in, immunosuppression was reduced because of an infection; the graft then developed microvascular injury and inflammation that progressed to organ failure. An earlier episode of T-cell-mediated rejection had resolved with treatment. No pig-pathogen transmission was detected.
• Human kidney, January 2026: immediate graft function; follow-up found no sensitisation from the pig organ — the key question for the bridging concept, since prior exposure to foreign tissue can make a later human transplant harder.
• Proposed role: the authors (Leonardo Riella, lead; Tatsuo Kawai, senior) position xenotransplantation as a bridge off dialysis for patients waiting for a human organ, and potentially a destination therapy once long-term safety and durability are shown. Riella: "The organ shortage is the greatest crisis we have right now in transplantation."

What is flagged as unproven

• This is one patient. The microvascular injury seen in the pig graft has, in the authors' words, implications for immunosuppression strategy, donor gene editing and monitoring in future trials — i.e. the failure mode is not yet solved.
• Durability of pig grafts beyond ~9 months, and whether the no-sensitisation finding holds across patients, are open.
• Funding came from MGH and eGenesis; several authors report eGenesis grants, consulting, employment or stock.

Wikilinks

Xenotransplantation — concept page: gene-edited pig organs, the bridge-vs-destination distinction, the sensitisation question. Edible Medical Sensors (Economist) — the other medical-device thread in this health topic. The Economist — Science & technology.

Captured-by trigger

Source file: raw/processed/Economist 2026-09-12 Science---Techn - A transplanted pig kidney buys time for a human one to.md (lede only).