Pig organ transplant inches closer with trial in dead

In this photo provided by NYU Langone Health, surgeons prepare a genetically modified pig heart for transplant into a recently deceased donor on Wednesday, July 6, 2022 at NYU Langone Health in New York.  The experiments are raising new hope that pigs may one day help make up for the shortage of donated organs—at least, for those in need of new hearts or kidneys.  (Joe Carotta/NYU Langone Health via AP)

In this photo provided by NYU Langone Health, surgeons prepare a genetically modified pig heart for transplant into a recently deceased donor on Wednesday, July 6, 2022 at NYU Langone Health in New York. The experiments are raising new hope that pigs may one day help make up for the shortage of donated organs—at least, for those in need of new hearts or kidneys. (Joe Carotta/NYU Langone Health via AP)

AP

Researchers in New York transplanted pig hearts into two brain-dead people last month, the latest in a string of developments in a day-long quest to save human lives with animal parts.

The experiments announced Tuesday come after a historic but failed attempt earlier this year to use a pig’s heart to save a dying Maryland man – before scientists tried again to help him survive a rehearsal.

In Lessons: It is important to practice with the deceased.

“We learned so much from the first that the second is much better,” said Dr. Nader Moazmi, who led the operation at NYU Langone Health. “You stand there in awe” when the pig’s heart starts beating in the human body.

This time, Moazmi’s team mimicked how routine heart transplants are performed. Once last month and once last week, researchers traveled to a facility housing genetically modified pigs, removed the needed hearts, put them on ice and drove them hundreds of miles back to New York.

They used special new methods to screen for any worrisome animal viruses before stitching hearts into the chest of each deceased recipient—a Vietnam veteran from Pennsylvania with a long history of heart disease and a New York woman who had previously undergone transplants. Life was beneficial.

Then came three days of more intensive testing than the surviving patients—which included repeated biopsies of the organ—before doctors cut life support.

Already the Food and Drug Administration is considering whether to allow a small number of Americans who need a new organ to volunteer for a rigorous study of a pig’s heart or kidney. NYU is one of three transplant centers planning the Langone trial — and has planned a meeting with the FDA in August to discuss the requirements.

Testing in the deceased could help fine-tune earlier tests in the living, said Dr David Klaasen of the United Network for Organ Sharing, which oversees the country’s transplant system.

“They serve as an important step of the way,” said Klaasen, who wonders whether researchers should consider tracking organs in donated bodies for a week or so, rather than the next three days. can.

Animal-to-human transplantation, which scientists call xenotransplantation, has been tried without success for decades, as people’s immune systems attack foreign tissue almost immediately. Now, pigs are being genetically modified so that their organs are more human-like – with growing hope that they may one day help make up for the shortage of donated organs. There are more than 100,000 people on the national waiting list for transplants, most of them kidney patients, and thousands die each year before it’s their turn.

The most ambitious effort so far came in January, when doctors at the University of Maryland Medical Center transplanted a pig’s heart into a 57-year-old man. David Bennett lived for two months, proof that xenotransplantation was at least possible. But in the initial investigation, it was not found that there is an animal virus in this organ. What caused Bennett’s new heart failure and whether that virus played a role is still not known, researchers in Maryland reported recently in the New England Journal of Medicine.

Months ago, the NYU team and researchers at the University of Alabama at Birmingham were testing pig kidney transplants in isolated deceased who had donated their bodies to science.

NYU’s recent heart experiments will add to the evidence as the FDA decides whether to allow formal studies in living patients.

But Dr. Robert Montgomery of NYU Langone, a kidney transplant surgeon who received his heart transplant, said it is important to continue careful experimentation in the deceased to find out the best practices “in a setting where a person’s life is not at risk.” Is.”

“This is not a one-time situation. It’s going to be years of learning what’s important to work with and what’s not important,” said Montgomery, who has a list of about 50 people who have said desperately to volunteer for pig kidney transplants.

The FDA has not indicated how soon it can decide whether to allow such studies. At a recent two-day public meeting, the agency’s scientific advisers said the time had come to make an effort, despite the long list of questions. They include how to best modify the pigs, as several biotech companies — including Revivcor, which supplies NYU organs — are pursuing different options.

It is also not clear which organ to try first in a clinical trial. If the pig kidney fails, the patient can always survive on dialysis. Yet some FDA advisors said it might be better to start with the heart. Experiments with pig kidneys in dead humans showed that the organs produced urine. But what is still unknown is whether pig kidneys perform another important job – processing drugs – in the same way that human kidneys do.

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The Associated Press Department of Health and Science receives support from the Howard Hughes Medical Institute’s Department of Science Education. AP is solely responsible for all content.

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