Difelikefalin improves itch in patients with chronic kidney disease
Click Here to Manage Email Alerts
Key takeaways:
- Patients with chronic kidney disease (CKD) treated with difelikefalin 1 mg experienced statistically significant improvements in itch.
- This study included patients with CKD treated with and without dialysis.
Itch intensity was reduced in patients with chronic kidney disease and moderate to severe pruritus who were treated with oral difelikefalin, according to a study.
“Pruritus is a common, distressing condition that has been well characterized in patients receiving hemodialysis (HD),” Gil Yosipovitch, MD, of the department of dermatology and cutaneous surgery at the Miami Itch Center, University of Miami Miller School of Medicine, and colleagues wrote. “Until recently, treatment of pruritus in HD patients has largely consisted of dialysis optimization and off-label therapies (topical corticosteroids, antihistamines, gabapentin).”
Intravenous difelikefalin was approved for use in patients undergoing HD in 2021; however, pruritus is often common in patients with non-dialysis-dependent chronic kidney disease (NDD CKD) as well and there are currently no approved treatments for pruritus in these patients.
This multicenter, randomized, double-blind, placebo-controlled phase 2 study evaluated the efficacy of three difelikefalin oral doses — 0.25 mg , 0.5 mg and 1 mg — in both HD and NDD patients with CKD.
Subjects were randomly assigned to receive one of the three dose levels or placebo once daily for 12 weeks.
A patient-reported 11-point itch intensity scale was evaluated throughout the study period.
Of the 269 study subjects, 59.1% had stage 3 NDD-CKD, 23% had stage 4-5 NDD-CKD and 17.8% had stage 4-5 CKD and were undergoing HD.
Starting at week 2 and continuing through week 12, patients in the 1 mg group had greater improvement in weekly mean worst itch score compared with placebo, with 38.6% of these patients achieving complete response at week 12 compared with 14.4% of those receiving placebo.
WI-NRS score improvements of at least 3 points and at least 4 points were reported in 72.1% and 64.8% of the 1 mg treatment group, respectively, compared with 57.9% and 49.8% of the placebo group.
Quality of life measurements increased by approximately 20% in the patients taking difelikefalin.
Treatment-emergent adverse events were mostly mild or moderate with diarrhea, nausea, fatigue and dizziness being the most commonly reported reasons for treatment discontinuation.
“In this phase 2 trial of subjects with CKD and moderate to severe pruritus, daily treatment with difelikefalin 1 mg resulted in significant reductions in itch intensity compared with placebo, as assessed by the primary outcome of the WI-NRS at week 12,” the study authors wrote. “Although difelikefalin 1 mg achieved statistical significance compared with placebo for the primary endpoint, the placebo response was higher than in previous studies of IV difelikefalin for CKD-associated pruritus. One explanation may be the more heterogeneous population compared with subjects undergoing HD.”