The kidney was taken from a genetically modified pig to stop the body from rejecting the organ as “foreign.”
The recipient of the pig’s kidney was on artificial life support and was brain dead with no prospect of recovering.
During the operation at the New York University Langone Health medical centre, surgeons connected the kidney to the blood vessels of the recipient. Over the next two-and-a-half days, they monitored the kidney and ran various tests.
Lead investigator Dr Robert Montgomery told the BBC’s World Tonight programme: “We observed a kidney that basically functioned like a human kidney transplant, that appeared to be compatible in as much as it did all the things that a normal human kidney would do.
“It functioned normally, and did not appear to be undergoing rejection.”
Experiments of a similar nature have been completed in primates, but never in a human.
Experts have said this is a huge advancement in the field. The work is yet to be peer-reviewed or published.
Pig heart valves are already widely used in humans. Organs from pigs are a good match to humans as they are a good size match.
Dr Montgomery says there is an urgent need to find more donors.
“The traditional paradigm that someone has to die for someone else to live is never going to keep up.
“I certainly understand the concern and what I would say is that currently about 40% of patients who are waiting for a transplant die before they receive one.
“We use pigs as a source of food, we use pigs for medicinal uses - for valves, for medication. I think it’s not that different.”
A spokesperson for NHS Blood and Transplant said to the BBC matching more human donors remained a priority in the UK. “There is still some way to go before transplants of this kind become an everyday reality.
“While researchers and clinicians continue to do our best to improve the chances for transplant patients, we still need everyone to make their organ donation decision and let their family know what they want to happen if organ donation becomes a possibility.”