PHOTOS: Genetically-modified pig saves heart patient; offers hope for millions more

David Bennett, a resident of Maryland in the United States has become the first person in the world to get a heart transplant from a genetically-modified pig. The 57-year-old, who suffered from terminal heart disease, received a successful transplant of a genetically-modified pig heart and is doing well three days later. 

The first of its kind transplant was the sole hope for Bennett who had been deemed ineligible for a traditional transplant. The landmark surgery, conducted by the University of Maryland School of Medicine faculty at the University of Maryland Medical Center, has given a ray of hope for those who have to wait for months to avail a transplant. Watch this story HERE

The surgery also demonstrated that a genetically-modified animal heart can function as a human heart without immediate rejection by the body. Bennett will be monitored over the next days and weeks to determine whether the transplant provides lifesaving benefits. To recall, the US Food and Drug Administration granted emergency authorization for the surgery on New Year's Eve through its expanded access (compassionate use) provision. The compassionate use authorisation is granted when an experimental medical product may be deemed as the last ray of hope for a patient. In Benett's case, it was a genetically-modified pig’s heart.

To make the heart suitable for transplant, 10 unique gene edits were made in the donor pig. Doctors removed three genes responsible for rapid antibody-mediated rejection of pig organs by humans in the donor pig. At the same time, six human genes that enabled immune acceptance of the pig heart were inserted into the genome. Besides, an additional gene in the pig was knocked out to prevent excessive growth of the pig heart tissue.

Speaking ahead of his surgery, Bennett said that for him it was either a do or die situation. Calling the transplant a shot in the dark, he said that the procedure was his last choice. Bennett, bedridden for the past few months, said he was looking forward to getting out of bed post-recovery. Bennett had been admitted to the hospital over six weeks ago with life-threatening arrhythmia. He had been connected to a heart-lung bypass machine -- extracorporeal membrane oxygenation -- to remain alive.

For five long years, the research team perfected the surgical technique for transplantation of pig hearts into non-human primates. Programme Director Dr Muhammad M Mohiuddin, whose xenotransplant research experience spans over 30 years, had authored in peer-reviewed research that genetically-modified pig's hearts can function when placed in the abdomen for as long as three years. Success relied on the genetic modifications made to the experimental donor pig UHeart and anti-rejection drugs, including some experimental compounds

Ahead of the transplant surgery, the surgical team, led by Dr Griffith and Dr Mohiuddin, removed the pig's heart and placed it in the XVIVO Heart Box to preserve it until surgery. The surgeons also used a new drug -- experimental compound made by Kiniksa Pharmaceuticals -- along with conventional anti-rejection drugs that were intended to suppress the immune system and stop the body from rejecting the foreign organ. 

Dr Bartley P Griffith, who surgically transplanted the pig heart, said that the breakthrough surgery had brought the world one step closer to resolving the organ shortage arising due to the lack of donor human hearts to meet the long list of potential recipients. According to data, in the United States alone, about 110,000 Americans are currently waiting for an organ transplant, and more than 6,000 patients die each year before getting one.

While asserting that they were proceeding cautiously with regard to the animal organ transplant, Dr Griffith said they were optimistic that this first-of-its-kind surgery would provide an important new option for patients in the future.

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