Profile
General Information
Korsuva (difelikefalin) is a kappa opioid receptor agonist.
Korsuva is specifically indicated for the treatment of moderate-to-severe pruritus associated with chronic kidney disease (CKD-aP) in adults undergoing hemodialysis.
Korsuva is supplied as a solution for intravenous injection. The recommended dosage is 0.5 mcg/kg administered by intravenous bolus injection into the venous line of the dialysis circuit at the end of each hemodialysis treatment. If a regularly scheduled hemodialysis treatment is missed, resume Korsuva at the end of the next treatment.
Mechanism of Action
Korsuva (difelikefalin) is a kappa opioid receptor (KOR) agonist. The relevance of KOR activation to therapeutic effectiveness is not known.
Side Effects
Adverse effects associated with the use of Korsuva may include, but are not limited to, the following:
- diarrhea
- dizziness
- nausea
- gait disturbances, including falls
- hyperkalemia
- headache
- somnolence
- mental status change
Clinical Trial Results
The FDA approval of Korsuva was based on the results of two phase 3 trials, KALM-1, conducted in the U.S. and the global KALM-2 trial.
The randomized, multicenter, double-blind, placebo-controlled trials enrolled a total of 851 subjects 18 years of age and older undergoing hemodialysis who had moderate-to-severe pruritus. In both trials, subjects received intravenous bolus injections of Korsuva 0.5 mcg per kilogram of dry body weight into the venous line of the hemodialysis circuit at the end of each hemodialysis session or placebo three times per week for 12 weeks. In both trials, a 7-day run-in period prior to randomization was used to confirm that each subject had moderate-to-severe pruritus and to establish a baseline itch intensity, as measured by the patient-reported daily 24-hour Worst Itching Intensity Numerical Rating Scale (WI-NRS) scores (0 “no itch” to 10 “worst itch imaginable”). The mean (SD) baseline WI-NRS score was 7.1 (1.5) in Trial 1 and 7.2 (1.4) in Trial 2. In each trial, efficacy was assessed based on the proportion of subjects achieving a 4-point or greater improvement (reduction) from baseline in the weekly mean of the daily 24-hour WI-NRS score at Week 12.
In KALM-1 the proportion of patients on 0.5 mcg/kg of Korsuva Injection achieving a three-point or greater improvement from baseline in the weekly mean of the daily 24 hour WI-NRS score at week 12 was 51% vs. 28% for patients on placebo.
In KALM-2 proportion of patients with three point or greater reduction in mean WI-NRS score versus placebo from baseline to week 12 was 54% versus 42%, respectively.