POS-601 IMPROVEMENT IN SLEEP QUALITY FROM REDUCTION OF ITCH INTENSITY IN PATIENTS WITH MODERATE-TO-SEVERE PRURITUS UNDERGOING HEMODIALYSIS

Abstract

Chronic kidney disease-associated pruritus (CKD-aP) is a common condition in patients with CKD undergoing hemodialysis (HD). Night-time pruritus may be a particularly burdensome symptom: In CKD-aP patients this results in poor sleep quality, an important marker of worse health-related quality of life (QoL). In phase 3 trials in patients with moderate-to-severe CKD-aP, difelikefalin (a peripherally restricted kappa-opioid receptor agonist), demonstrated significant improvements in itch intensity versus placebo at week 12, and improvements in sleep quality and itch-related QoL. The aim of the study was to evaluate the impact of reduced itch intensity on sleep quality among HD patients treated with difelikefalin or placebo in the KALM-1 and KALM-2 Phase 3 clinical trials. This post-hoc analysis used pooled data for all patients. Improvement from baseline to week 12 in itch intensity was evaluated by weekly mean of the 24-hour Worst Itching Intensity Numerical Rating Scale (WI-NRS) score (range 0 [no itch] to 10 [worst itch imaginable]). Change in sleep quality was assessed by the 5-D Itch scale sleep disability question (1 [never affects sleep] to 5 [delays falling asleep and frequently wakes me up at night]). Spearman’s correlation analysis was performed. Patients with a clinically meaningful (≥3-point) reduction in WI-NRS score had significantly greater improvements in mean 5-D Itch sleep disability question score (−1.5 vs −0.6 for <3-point WI-NRS score reduction; p<0.0001) from baseline to week 12 (n=709) (Figure ). A moderate correlation was observed between WI-NRS and 5-D Itch sleep disability question scores at week 12 (r =0.499, 95% confidence interval 0.442, 0.552). A significant improvement was also observed at the first assessment of sleep quality (4 weeks) for patients with a ≥3-point (vs <3-point) reduction in WI-NRS score (−1.2 vs −0.4, p<0.0001, n=761). Reduction of itch intensity correlates with improvement in sleep quality in HD patients.