Cara Therapeutics and Vifor Pharma Granted US FDA Approval of KORSUVA™ Indeed, the U.S. Food and Drug Administration (FDA) approved Cara Therapeutics (CARA) and Vifor Pharma injectable product KORSUVA™ (difelikefalin) - a first-in-class kappa opioid receptor (KOR) agonist that targets the body’s peripheral nervous system, for moderate-to-severe pruritus associated with chronic kidney . . . This content is for paid subscribers. Please click here to subscribe or here to …