Difelikefalin: First Approval.

Difelikefalin (Korsuva™) is a synthetic peptide agonist of the kappa opioid receptor being developed by Cara Therapeutics for the treatment of pruritus. In August 2021, intravenous difelikefalin was approved in the USA for the treatment of moderate-to-severe pruritus associated with chronic kidney disease (CKD) in adults undergoing haemodialysis. Intravenous difelikefalin has also been evaluated for CKD-associated pruritus in patients undergoing haemodialysis in various other countries, with Marketing Authorization Application under regulatory review in the EU and a phase III trial ongoing in Japan. Clinical studies of an oral formulation of difelikefalin have also been completed or are underway in pruritus indications, including pruritus associated with atopic dermatitis, notalgia paraesthetica or primary biliary cholangitis. This article summarizes the milestones in the development of difelikefalin leading to this first approval for CKD-associated pruritus in adults undergoing haemodialysis.