DifelikefalinSpecialist prescription medicine
Difelikefalin targets kappa-opioid receptors and has been developed for troublesome itch associated with chronic kidney disease in people receiving haemodialysis.
What is Difelikefalin?
Difelikefalin is a kappa-opioid-receptor agonist developed for troublesome chronic-kidney-disease-associated itch in people receiving haemodialysis.
How it works
It was designed to act largely outside the brain on kappa-opioid sensory and immune signalling. This itch pathway differs from those underlying many allergic symptoms.
Effects studied
Itch severity during haemodialysis
The KALM-1 placebo-controlled study assessed itch using symptom scales in adults on haemodialysis. Its findings belong to that treatment setting and do not establish an effect on all causes of itching. 1
Evidence: Placebo-controlled haemodialysis trial
What does the evidence show?
The archive includes the KALM-1 placebo-controlled trial. Its population, itch scale and treatment setting define what the result can tell us.
How dialysis-related itch differs
Persistent itch can seriously disrupt sleep and everyday life during dialysis. It does not necessarily arise through the same pathways as an allergy or eczema. Difelikefalin was designed to act largely outside the brain on kappa-opioid signalling associated with sensory and immune pathways.
How the trial measured itch relief
An itch trial asks people how severe the symptom feels and whether that burden changes. A prespecified improvement on a scale is more informative than a laboratory marker alone. The retained KALM-1 paper compared treatment with placebo in adults receiving haemodialysis. 1
Route and setting remain specific
The intravenous treatment is associated with the dialysis session. A result in that setting cannot establish that an oral or unverified injectable preparation would work similarly, or that the same benefit applies to people with a different cause of itch.
Peripheral does not mean free of side effects
Dizziness, drowsiness, gastrointestinal symptoms and falls deserve attention in the relevant product information. Limiting brain exposure does not rule out neurological effects. The balance of symptom relief and treatment burden is individual; current European and Swiss eligibility should be checked separately. 2
Safety & status
Dizziness, drowsiness, gastrointestinal symptoms and falls are relevant adverse effects. Limited brain exposure does not mean neurological effects are impossible. 2
Country and product status
This introduction describes the molecule and its research context. Product availability, approved indications and eligibility in Germany and Switzerland require a current local product check; they are not established by an overseas study or an online listing.
Frequently asked questions
Is this an antihistamine?
No. It targets kappa-opioid signalling rather than the histamine pathway.
Can its dialysis results be applied to eczema?
Not directly. The cause of itch, population and formulation would need relevant evidence of their own.
Sources
This entry was rewritten from our research archive. References below are reading leads unless a completed check is explicitly noted; a full independent evidence and regulatory review is still pending.
- Difelikefalin: paper 10.1056/NEJMoa1912770 Research reference · Retained archive reference; not independently checked for this draft.
- Difelikefalin: www.drugs.com reference Reference or product information · Retained archive reference; not independently checked for this draft.
Research provenance
This name was discovered in the Superpower peptide index, archived 26 October 2026. Its ratings and reviewer attribution have not been adopted as our own. The archive informed this original editorial draft; independent source review is still pending.