Chinese researchers are reporting new steps in the quest for animal-to-human organ transplants. Researchers at Xijing Hospital in China say a pig kidney transplant recipient continues to recover nearly three weeks after that surgery.

Chinese researchers have reported new advancements in the pursuit of animal-to-human organ transplants, successfully transplanting a genetically modified pig kidney into a human patient and making progress toward the potential use of pig livers.

These advances have made it possible for scientists to create pigs with organs that are more compatible with human biology, thus reducing the chances of rejection. One common edit, for instance, removes a pig’s ability to produce alpha-gal, a sugar that the human body doesn’t make.