U.S. biotech company United Therapeutics announced on Monday that it has completed the first clinical transplant of a gene-edited pig kidney into a human at NYU Langone Health, marking the formal launch of the world’s first large-scale clinical trial of this kind.

According to U.S. media reports, the trial is the first FDA-approved program to systematically evaluate the safety and efficacy of gene-edited pig kidneys for patients with end-stage renal disease. It follows several previous “compassionate use” xenotransplant procedures conducted on critically ill patients.