Second person to receive pig kidney transplant must return to dialysis

NYU Langone Health, which performed the kidney removal, said the patient was stable. Pisano had undergone a transplant of genetically modified pig kidneys and a mechanical heart pump in April.

Initially, she recovered well. But managing both the heart pump and the new kidney “presented unique challenges,” said Dr. Robert Montgomery, who led the surgical team. To optimize blood flow to the kidney, Pisano’s blood pressure dropped several times a day. As a result, the kidney failed, and doctors could no longer keep her on immunosuppressants.

The biopsy results showed that the kidney was not rejected, which is the biggest concern in experimental animal-to-human transplants. However, the kidney suffered significant damage due to inadequate blood flow. After the surgery, NYU Langone Health will study the pig kidney’s response in a living human.

Dr. Montgomery noted that Pisano's condition was quite severe before the surgery. Her heart condition made a traditional transplant impossible.

"We hope to bring Lisa home to her family soon. Her strength and courage in the face of adversity has inspired and motivated us to pursue the hope of xenotransplantation," he said.

In an interview in April, Pisano said she knew the pig kidneys might not work. “I just took a chance. Worst case scenario, it doesn’t work for me, it still works for other people,” she said.

The first patient to receive a pig kidney, Richard "Rick" Slayman, died in early May, nearly two months after the transplant. Doctors said there was no indication that his death was due to the experiment.

More than 100,000 Americans are currently on the waiting list for organ transplants, most of them for kidneys. Thousands have died while waiting. Hoping to address the shortage, some biotech companies have genetically modified pigs to make their organs more human-like and less likely to be rejected if transplanted into humans.

Larger, more formal studies are expected to begin next year. Meanwhile, NYU Langone Health and other medical facilities have temporarily transplanted pig hearts and kidneys into brain-dead people, with promising results. In addition to the pig kidney transplant, the University of Maryland also transplanted pig hearts into two men who had no other treatment options. Both died within months.