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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.

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Corresponding author

Correspondence to Emma D. Deeks.

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The preparation of this review was not supported by any external funding.

Authorship and Conflict of interest

During the peer review process the manufacturer of the agent under review was offered an opportunity to comment on the article. Changes resulting from any comments received were made by the authors on the basis of scientific completeness and accuracy. Emma Deeks is a contracted employee of Adis International Ltd/Springer Nature, and declares no relevant conflicts of interest. All authors contributed to the review and are responsible for the article content.

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Not applicable.

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This profile has been extracted and modified from the AdisInsight database. AdisInsight tracks drug development worldwide through the entire development process, from discovery, through pre-clinical and clinical studies to market launch and beyond.

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Deeks, E.D. Difelikefalin: First Approval. Drugs 81, 1937–1944 (2021).

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