The U.S. Food and Drug Administration (FDA) has approved the first-ever clinical trials to transplant genetically modified pig kidneys into people with kidney failure.
These trials are being conducted by two biotech firms: United Therapeutics Corporation and eGenesis.
Trial Design & Participants
- United Therapeutics’ study will begin with six patients suffering from end-stage renal disease, then expand to 50 participants if early results are promising.
- eGenesis will start with three patients, with plans for staged expansion.
- Eligible patients are those on dialysis for at least six months, usually aged between 55 and 70, and unable to get a human kidney transplant or unlikely to receive one within five years.
- There will be careful monitoring, including a 24-week follow-up period post-transplant, and lifelong surveillance of patients.
Why This Is a Big Deal
- There are hundreds of thousands of people in the U.S. living with kidney failure, many of whom die waiting for a donor organ. These trials could help alleviate that severe organ shortage.
- The pig kidneys are genetically modified to reduce risks of rejection and to inactivate certain pig-virus genes.
- If successful, this could open the door to xenotransplantation (animal → human organ transplants) as a more standard solution.
Challenges & Risks
- Immune Rejection remains a serious risk, even with gene editing. The human body may still react in unpredictable ways.
- Cross-species disease transmission is a concern: potential for zoonotic pathogens. Even though pigs are being modified and raised in controlled environments, absolute safety is not guaranteed
- Ethical and consent issues: Patients must fully understand unknown risks. Long-term effects are not yet known.
- Cost, scalability, and regulatory oversight will be significant hurdles. Will insurance cover these? Can the supply of gene-edited pig organs be scaled?
What’s Already Happened
- Earlier experimental surgeries under compassionate use have already taken place, including one at Massachusetts General Hospital in March 2024, where a 62-year-old man (Richard Slayman) received a genetically edited pig kidney transplant. Reuters
- These previous surgeries provide some proof-of-concept, though long-term function and safety still require rigorous trial data.
What To Watch Next
- The first transplants under the new trials are expected mid-2025.
- Key metrics to monitor: survival duration of transplanted kidneys, functionality (filtration, urine production etc.), patient outcomes, adverse events, immune rejection, and quality of life.
- Regulatory reviews: the results will be closely watched by FDA and other agencies, which will inform future approvals.
- Public acceptance and ethics: how patients, doctors, and society respond will also influence how widely xenotransplantation is adopted.
