Key takeaways:

• Tim Andrews, a 66-year-old New Hampshire man, is the second person to receive a genetically modified pig kidney transplant.
• This landmark surgery took place at Massachusetts General Hospital on January 25, providing hope to others suffering from end-stage kidney disease.
• The procedure was authorized under the FDA's Expanded Access pathway, allowing critically ill patients access to experimental therapies.
• Advancements in genetic engineering, including CRISPR technology, have enabled the creation of more compatible pig organs for human transplantation.
• The initial success of pig kidney transplants may pave the way for broader applications, including other animal organs.

A 66-year-old man from New Hampshire, Tim Andrews, has made medical history as the second individual to receive a pig kidney transplant. His surgery marks a pivotal milestone in the field of xenotransplantation, a process where animal organs are transplanted into humans, aimed at addressing a critical shortage of donor organs. This significant achievement took place at Massachusetts General Hospital on January 25, 2025, and offered vibrant hope to individuals suffering from end-stage kidney disease.

Before receiving the transplant, Andrews had been on dialysis for over two years, facing a grim prognosis with merely a 9% chance of receiving a human kidney in the next five years due to his blood type. The surgery was part of a formal study approved by the FDA which will include three patients in total. Following his operation, Andrews left the hospital just a week later, and doctors reported that the transplanted kidney was functioning normally, producing urine without any signs of rejection.

This breakthrough is fueled by innovations in genetic engineering that enable the modification of pig organs to make them more compatible with human recipients. The pig kidney was developed by eGenesis, a biotech company that utilizes CRISPR technology to make specific gene edits, enhancing the organ's compatibility and reducing the risk of rejection. For example, in this case, the transplanted kidney had undergone significant genetic alterations, including the removal of proteins that would typically provoke an immune response in human hosts.

Doctors noted that such transplants have the potential to significantly alleviate the organ shortage crisis that affects approximately 90,000 people in the U.S. awaiting a kidney transplant. In recent years, nearly 50% of potential patients in critical condition faced the risk of being removed from transplant lists due to deteriorating health conditions exacerbated by prolonged dialysis. Although previous attempts at xenotransplantation have been met with mixed results, recent progress suggests a more hopeful future.

Massachusetts General Hospital's Dr. Leonardo Riella, who led Andrews' surgery, remarked that "xenotransplant represents a turning point by eliminating organ shortage as a barrier to transplant," reinforcing its potential as a transformative solution for kidney failure patients. He emphasized the importance of properly selecting candidates for such procedures, as less severely ill patients might benefit more from xenotransplants.

In parallel to Andrews' case, United Therapeutics has received FDA approval to begin clinical trials of their own genetically modified pig kidneys, with plans to introduce this alternative approach to kidney transplantation to up to 50 patients. These developments embody significant advancements towards more widespread utilization of animal organs in transplantation, a step that could reshape the future of organ donation.

Andrews expressed profound gratitude for the opportunity to receive the transplant, describing it as a "miracle" that delivered him from the despair of dialysis. He has committed to using his experience to inspire others waiting for a kidney, indicating that this innovation is not only personal but offers a "glimmer of hope" for many.