Difelikefalin
Difelikefalin is the kappa-opioid-receptor agonist in KORSUVA, used for moderate-to-severe itching associated with chronic kidney disease in adults receiving hemodialysis.
At a glance
- Evidence stage
- Approved use
- Regulatory status
- KORSUVA is US-approved for moderate-to-severe CKD-associated pruritus in adults undergoing hemodialysis; this does not cover all causes of itching.
- Research context
- Difelikefalin is the kappa-opioid-receptor agonist in KORSUVA, used for moderate-to-severe itching associated with chronic kidney disease in adults receiving hemodialysis.
What this is
- Difelikefalin is the kappa-opioid-receptor agonist in KORSUVA, used for moderate-to-severe itching associated with chronic kidney disease in adults receiving hemodialysis.
What this isn't
- A recommendation to use, prepare, combine, or administer a product
- Evidence that a related molecule or a differently formulated product has the same effects
Key terms
Difelikefalin is the kappa-opioid-receptor agonist in KORSUVA, used for moderate-to-severe itching associated with chronic kidney disease in adults receiving hemodialysis.
Difelikefalin activates kappa opioid receptors. The label does not equate that receptor activity with a fully established explanation of its clinical benefit. Its clinical role is relief of a specific symptom in a defined dialysis population, rather than correction of kidney failure or a general analgesic claim. Product label.
Evidence limits
How to read the evidence
The trials support symptom benefit over a limited controlled follow-up and include a substantial placebo response. KORSUVA has not been studied adequately for peritoneal dialysis and is not recommended for that population in the label. Results do not establish effectiveness for allergic, dermatologic, or unexplained itch. Product-specific scope.
Sources appraised 2026-10-28. Educational information; not medical advice. Study findings apply to the populations, preparations and outcomes described.
External sources and citations
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