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What is Difelikefalin and explain in detail?
Difelikefalin, sold under the brand name Korsuva, is an analgesic opioid peptide used for the treatment of moderate to severe itching. It acts as a peripherally specific, highly selective agonist of the κ-opioid receptor (KOR).Difelikefalin was approved for medical use in the United States in August 2021.Difelikefalin acts as an analgesic by activating KORs on peripheral nerve terminals and KORs expressed by certain immune system cells. Activation of KORs on peripheral nerve terminals results in the inhibition of ion channels responsible for afferent nerve activity, causing reduced transmission of pain signals, while activation of KORs expressed by immune system cells results in reduced release of proinflammatory, nerve-sensitizing mediators (e.g., prostaglandins).

Society and culture
Legal status
On 24 February 2022, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Kapruvia, intended for treatment of moderate-to-severe pruritus associated with chronic kidney disease