Pig Kidney Transplants Show Promise as Clinical Trials Begin

A Massachusetts hospital has achieved a significant milestone in transplant medicine. They announced that a second patient, a man from New Hampshire, has successfully received a pig kidney and is recovering well. This announcement coincides with U.S. regulators giving the green light for comprehensive clinical trials.

Bill Stewart, a 54-year-old athletic trainer, underwent the procedure on June 14 at Massachusetts General Hospital. He expressed his desire to contribute to scientific advancement, describing himself as someone with a keen interest in science.

Stewart's case follows that of another patient, Tim Andrews, who has lived for over seven months with a pig kidney. This represents the longest known survival period for such a transplant. Previously, the longest survival time for a gene-edited pig organ was 130 days.

The Food and Drug Administration has authorized eGenesis, a biotechnology company, to initiate a clinical study involving 30 dialysis patients aged 50 or older who are on the transplant waiting list. Another company, United Therapeutics, is also preparing a similar trial.

Dr. Leonardo Riella, a kidney specialist at Mass General, highlighted the current shortage of human organs. He explained that over 100,000 Americans are awaiting transplants, with the majority needing kidneys. Thousands of people die each year while waiting for a suitable organ.

Scientists are exploring genetically engineered pigs as a solution. They modify the animals' organs to make them more compatible with the human body and less likely to be rejected by the immune system. Early attempts, involving heart and kidney transplants, had limited success. More recent procedures, like those involving Stewart and Andrews, focus on patients who are in relatively better health.

Stewart's kidneys failed due to high blood pressure. After two years on dialysis and with no suitable donor available, he opted for the experimental procedure. He even consulted with Andrews before making his decision. He acknowledged that the pig kidney could be removed if necessary.

Since the surgery, Stewart has gradually returned to work and recently visited his former dialysis clinic to share his experience with other patients. He hopes to offer them a sense of optimism.

Dr. Riella noted that both Stewart and Andrews required adjustments to their anti-rejection medications. However, he emphasized that even temporary success could significantly improve patient care. He explained that pig kidneys could provide patients with valuable time off dialysis while they await a human organ.

The field of xenotransplantation is still in its early stages. However, researchers believe that the current results and the upcoming clinical trials suggest that animal-to-human organ transplants could eventually become a standard medical practice.