Efficacy and Safety of Difelikefalin in Japanese Patients With Moderate to Severe Pruritus Receiving Hemodialysis: A Randomized Clinical Trial

From Compression to Itch: Exploring the Link Between Nerve Compression and Neuropathic Pruritus

Neuropathic itch is a type of chronic pruritus resulting from neural dysfunction along the afferent pathway. It is often accompanied by abnormal sensations such as paresthesia, hyperesthesia, or hypoesthesia. This condition, which may involve motor or autonomic neural damage, significantly impacts patients' quality of life, causing severe itch and associated comorbidities such as depression, disrupted sleep, and social strain. Neuropathic itch accounts for 8% of chronic pruritus cases, though this may be underestimated. This comprehensive review focuses on nerve impingement as the primary pathophysiological mechanism for various forms of neuropathic itch including brachioradial pruritus (BRP), notalgia paresthetica (NP), and anogenital itch. BRP, often seen in middle-aged white women, manifests as pruritus in the dorsolateral forearms typically exacerbated by ultraviolet (UV) exposure and related to cervical spine pathology. NP, prevalent in middle-aged women, presents as pruritus in the upper back due to thoracic spine nerve compression. Anogenital pruritus, affecting 1-5% of adults, is often linked to lumbosacral spine issues after ruling out dermatologic conditions such as lichen sclerosus or lichen simplex chronicus. The pathophysiology of neuropathic itch involves both peripheral and central mechanisms, with nerve damage being a key factor. Diagnosis requires a thorough history, physical examination, and potentially imaging studies. Topical agents such as menthol, capsaicin, and lidocaine are used for mild cases, while systemic medications such as gabapentin, pregabalin, and antidepressants are prescribed for moderate to severe cases; however, no US Food and Drug Administration (FDA)-approved therapies currently exist specifically for neuropathic itch. Understanding the underlying neural dysfunction and appropriate therapeutic strategies is crucial for managing neuropathic itch effectively.

Difelikefalin in the treatment of hemodialysis patients with pruritus: a systematic review and meta-analysis

Background and Objective

Uremic pruritus is a persistent condition that is difficult to cure in patients with end-stage renal disease who are having regular dialysis. It is highly prevalent, and current therapies have limited effectiveness and can cause significant adverse effects. Several trials have provided evidence that difelikefalin can be an effective treatment for uremic pruritus, with few side responses. However, it is important to note that the available evidence is limited. This study collected published randomized controlled trials for systematic review and Meta-analysis, to explore the efficacy and safety of difelikefalin treating uremic pruritus and to provide evidence-based medical evidence for clinical treatment.

Methods

A systematic literature search was conducted in PubMed, EMBASE, Web of Science, the Cochrane Library Data from building libraries to 6 January 2024. We extracted data from eligible studies to analyze the efficacy and safety of difelikefalin in the treatment of hemodialysis patients with pruritus.

Results

This study comprised 9 trials with 4,118 people. The meta-analysis demonstrated that difelikefalin is more effective than placebo in treating uremic pruritus. Specifically, difelikefalin resulted in a greater improvement in WI-NRS scores of at least 3 points from baseline (OR = 1.98) and at least 4 points from baseline (OR = 1.94). Additionally, difelikefalin led to a decrease in the total score of the 5-D itch scale (MD = 1.56), a decrease in the skindex-10 scale score (MD = 4.92), and a decrease in the WI-NRS scale score (MD = 0.91).

Conclusion

Difelikefalin demonstrates significant efficacy in alleviating pruritus in individuals suffering from uremia. Althogh it has adverse events, they are mild.

The efficacy and safety of difelikefalin for pruritus in hemodialysis patients: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Chronic kidney disease-associated pruritus (CKD-ap) is a common complication that negatively affects the quality of life. Difelikefalin has emerged as a novel FDA-approved drug to manage CKD-ap. This systematic review and meta-analysis will assess the efficacy and safety of Difelikefalin versus placebo to manage CKD-ap.

METHODS

PubMed, Scopus, WOS, Central, and Embase were systematically searched until November 2023. RevMan was used to perform meta-analysis. Quality assessment was conducted using the Cochrane RoB 2.0 tool. Results were reported as risk ratio (RR) and mean difference (MD) with a 95% confidence interval (CI). PROSPERO ID: (CRD42023485979).

RESULTS

Five RCTs with a total of 896 participants were included. Difelikefalin significantly decreased the weekly mean WI-NRS score (MD: -0.99 [-1.22, -0.75], p ˂ .00001), 5-D itch scale total score (MD: -1.51 [-2.26, -0.76], p > .0001), and Skindex-10 total score (MD: -7.39 [-12.51, -2.28], p = .005), but showed significantly higher adverse events (RR: 1.26 [1.03, 1.55], p = .03), versus placebo. However, there was no significant difference between both groups in serious adverse events (RR: 1.42 [0.78, 2.57], p = .25) or death (RR: 0.81 [0.19, 3.34], p = .77).

CONCLUSION

Difelikefalin appears to be a promising agent for the management of CKD-induced pruritus in patients with end-stage renal disease. However, evidence is still underpowered due to the paucity of the current data; therefore, more robust RCTs are required to confirm the benefit of Difelikefalin.

The role of blood purification therapies in the treatment of chronic kidney disease-associated pruritus: a systematic review

Chronic kidney disease-associated pruritus (CKD-aP) is a common complication in dialysis patients which is not fully addressed by pharmacological and dialytic therapy. The objective was to review the literature on the effects of extracorporeal blood purification modalities on CKD-aP. The population comprised patients aged ≥18 years on chronic dialysis. PubMed, Embase, and Medline were systematically searched until February 2024 for clinical studies comparing the effect of different dialysis modalities on pruritus intensity. Two reviewers extracted data independently. Risk of bias for randomized controlled trials (RCTs) was assessed using the Cochrane tool. Any extracorporeal blood purification therapy for the treatment of CKD-aP was included. Outcome was quantitative change in pruritus intensity on a validated itching scale. This review included eight RCTs examining five different dialysis modalities, three observational studies examining three dialysis modalities, and six prospective clinical trials assessing four dialysis modalities. These treatments included peritoneal dialysis, low-flux and high-flux dialysis, hemodiafiltration, expanded hemodialysis, hemadsorption, hemodiafiltration with endogenous reinfusion and dialysis with polymethylmethacrylate membrane. Risk of bias was high in most studies. The largest body of evidence was found for the efficacy of hemadsorption. Limitations of evidence included heterogeneity in diagnostic tools and treatment, risk of selection bias, small sample sizes and short follow-up durations that made it challenging to perform a robust systematic review and meta-analysis. Despite the high prevalence of pruritus among dialysis patients, current evidence for efficacy of standard dialytic treatment is weak. The only technique that appears to be effective is hemoadsorption alone or coupled with hemodialysis. More high-quality studies are needed to confirm the long-term benefits.

Advances in GPCR-targeted drug development in dermatology

Achieving the efficacy and specificity of G-protein-coupled receptor (GPCR) targeting-drugs in the skin remains challenging. Understanding the molecular mechanism underlying GPCR dysfunction is crucial for developing targeted therapies. Recent advances in genetic, signal transduction, and structural studies have significantly improved our understanding of cutaneous GPCR functions in both normal and pathological states. In this review, we summarize recent discoveries of pathogenic GPCRs in dermal injuries, chronic inflammatory dermatoses, cutaneous malignancies, as well as the development of potent potential drugs. We also discuss targeting of cutaneous GPCR complexes via the transient receptor potential (TRP) channel and structure elucidation, which provide new opportunities for therapeutic targeting of GPCRs involved in skin disorders. These insights are expected to lead to more effective and specific treatments for various skin conditions.

[Clinical Research Progress on Using κ-Opioid Receptor Agonists to Treat Uremic Pruritus]

Uremic pruritus, a severe complication in patients with chronic kidney disease, is associated with a high prevalence. It can cause depression and sleep disorders, and seriously affect the quality of life and the social relations of patients. Recently, there is growing evidence showing that κ-opioid receptor agonists, including nalfurafine, difelikefalin, and nalbuphine, can effectively and safely reduce itching symptoms in patients with refractory uremic pruritus. Herein, we reviewed the epidemiology, pathogenesis, clinical symptoms, and treatment strategies of uremic pruritus, and summarized in detail the progress in clinical research on the use of κ-opioid receptor agonists, including nalfurafine, difelikefalin, and nalbuphine, in the management of patients with uremic pruritus.

Chronic Pruritus: A Review

Importance

Chronic pruritus, defined as itch experienced for 6 weeks or longer, affects approximately 22% of people in their lifetime. Approximately 1% of physician visits are for the chief concern of chronic pruritus. Chronic pruritus is associated with adverse outcomes, including impaired sleep and reduced quality of life.

Observations

Chronic pruritus can be categorized by etiology into inflammatory, neuropathic, or a combination of inflammatory and neuropathic pruritus. Chronic pruritus is due to inflammation in approximately 60% of patients and may be caused by eczema, psoriasis, or seborrheic dermatitis. Chronic pruritus is due to a neuropathic or mixed etiology in approximately 25% of patients. Neuropathic causes of chronic pruritus include postherpetic neuralgia and notalgia paresthetica and are typically due to localized or generalized nerve dysregulation. Approximately 15% of people with chronic pruritus have other causes including systemic diseases with secondary itch, such as uremic pruritus and cholestatic pruritus, medication-induced pruritus such as pruritus due to immunotherapy, and infectious etiologies such as tinea corporis and scabies. When few primary changes are present, a thorough history, review of symptoms, and laboratory evaluation should be performed, particularly for people with chronic pruritus lasting less than 1 year. Clinicians should consider the following tests: complete blood cell count, complete metabolic panel, and thyroid function testing to evaluate for hematologic malignancy, liver disease, kidney disease, or thyroid disease. First-line treatment for inflammatory chronic pruritus includes topical anti-inflammatory therapies such as hydrocortisone (2.5%), triamcinolone (0.1%), or tacrolimus ointment. Approximately 10% of patients do not respond to topical therapies. In these patients, referral to dermatology and systemic oral or injectable treatments such as dupilumab or methotrexate may be considered. When no underlying systemic disease associated with pruritus is identified, patients are likely to have neuropathic chronic pruritus or mixed etiology such as chronic pruritus of unknown origin. In these patients, neuropathic topical treatments such as menthol, pramoxine, or lidocaine can be used either alone or in combination with immunomodulatory agents such as topical steroids. Other effective therapies for neuropathic pruritus include gabapentin, antidepressants such as sertraline or doxepin, or opioid receptor agonist/antagonists such as naltrexone or butorphanol.

Conclusions and Relevance

Chronic pruritus can adversely affect quality of life and can be categorized into inflammatory, neuropathic, or a combined etiology. First-line therapies are topical steroids for inflammatory causes, such as hydrocortisone (2.5%) or triamcinolone (0.1%); topical neuropathic agents for neuropathic causes, such as menthol or pramoxine; and combinations of these therapies for mixed etiologies of chronic pruritus.

Efficacy and safety of different systemic drugs in the treatment of uremic pruritus among hemodialysis patients: a network meta-analysis based on randomized clinical trials

Aim

This network meta-analysis was to analyze and rank the efficacy and safety of different systemic drugs in the treatment of uremic pruritus (UP) among hemodialysis patients.

Method

PubMed, Embase, Cochrane Library, and Web of Science databases were searched from inception to 10 July 2023 for randomized controlled trials (RCTs) investigating different drugs in the treatment of UP among hemodialysis patients. Drugs including cromolyn sodium, dexchlorpheniramine, difelikefalin, gabapentin, hydroxyzine, ketotifen, melatonin, montelukast, nalbuphine, nalfurafine, nemolizumab, nicotinamide, pregabalin, sertraline, thalidomide, and placebo were assessed. Outcome measures, including pruritus relief, response, and adverse events, were analyzed. Network plots, forest plots, league tables, and the surface under the cumulative ranking (SUCRA) probabilities were depicted for each outcome.

Results

The network meta-analysis retrieved 22 RCTs. Gabapentin (69.74%) had the highest likelihood to be the most effective drug for pruritus relief in UP patients receiving hemodialysis, followed by cromolyn sodium and hydroxyzine. Thalidomide (60.69%) and gabapentin (58.99%) were associated with significantly more drug responses for treating UP among patients receiving hemodialysis. Patients who were treated with gabapentin (40.01%) were likely to have risks of adverse events and dizziness. Lower risks of adverse events, nausea, and diarrhea were found in patients who received cromolyn sodium and lower risks of somnolence.

Conclusion

This study suggests considering gabapentin treatment when facing a patient suffering from UP. This study provides a reference for the selection of drug therapy for UP patients receiving hemodialysis.

Approach using the bath preparation containing rice extract for severe pruritus in a patient receiving hemodialysis: A case report

Severe pruritus in a hemodialysis patient who had difficulty applying topical medication markedly reduced with the use of bath preparation containing rice extract. The bath preparation could be effective and an option for treating pruritus.

Intravenous difelikefalin for the treatment of hemodialysis pruritus

INTRODUCTION

Patients with chronic kidney disease (CKD) undergoing hemodialysis often experience significant itch secondary to their condition and a subsequent reduction in their overall quality of life. Current treatments are underwhelming, necessitating the search for new, effective therapeutic options to combat itch in this population.

AREAS COVERED

The purpose of this review is to explore the available data for the use of intravenous difelikefalin in patients with CKD undergoing hemodialysis. The pathophysiology of CKD-associated itch is multifactorial, with one proposed mechanism involving an imbalance in the endogenous opioid system, favoring upregulation of itch-activating μ-opioid receptors (MORs) and downregulation of itch-inhibiting κ-opioid receptors (KORs). Dysregulation of the immune system is also involved. Difelikefalin is a recent FDA approved treatment that functions as peripherally acting KOR agonist, targeting this imbalance in the endogenous opioid system seen in CKD patients with itch and having an anti-inflammatory effect on immune cells. Clinical data on intravenous difelikefalin is promising regarding its ability to reduce itch in CKD patients on hemodialysis and improve patient quality of life, with few, mild adverse side effects.

EXPERT OPINION

As intravenous difelikefalin becomes more widely used in the clinical setting, further studies assessing long-term efficacy and safety will be needed.

Randomized controlled trial of nalfurafine for refractory pruritus in hemodialysis patients

Background: Chronic kidney disease-associated pruritus (CKD-aP) is very common and sometimes refractory to treatment in hemodialysis patients. In a trial conducted in Japan, nalfurafine, effectively reduced itching of treatment-resistant CKD-aP. Our present bridging study aimed to evaluate the efficacy and safety of nalfurafine in Chinese cohort with refractory CKD-aP.Methods: In this phase III, multicenter bridging study conducted at 22 sites in China, 141 Chinese cases with refractory CKD-aP were randomly (2:2:1) assigned to receive 5 μg, 2.5 μg of nalfurafine or a placebo orally for 14 days in a double-blind manner. The primary end point was the mean decrease in the mean visual analogue scale (VAS) from baseline.Results: A total of 141 patients were included. The primary endpoint analysis based on full analysis set (FAS), the difference of mean VAS decrease between 5 μg nalfurafine and placebo group was 11.37 mm (p = .041); the difference of mean VAS decrease between 2.5 μg and placebo group was 8.81 mm, but not statistically significantly different. Both differences were greater than 4.13 mm, which met its predefined success criterion of at least 50% efficacy of the key Japanese clinical trial. The per protocol set (PPS) analysis got similar results. The incidence of adverse drug reactions (ADRs) was 49.1% in 5μg, 38.6% in 2.5 μg and 33.3% in placebo group. The most common ADR was insomnia, seen in 21 of the 114 nalfurafine patients.Conclusions: Oral nalfurafine effectively reduced itching with few significant ADRs in Chinese hemodialysis patients with refractory pruritus.

Difelikefalin for Hemodialysis Patients with Pruritus in Japan

BACKGROUND: Difelikefalin, a peripherally specific selective agonist of kappa opioid receptors, has been approved for the treatment of pruritus in hemodialysis patients in the United States. However, there is limited evidence for postdialysis intravenous use in non-U.S. populations. METHODS: In this double-blind, placebo-controlled, phase 3 trial in Japan, patients with moderate to severe pruritus were randomly allocated 1:1 to receive either placebo or 0.5 μg/kg of difelikefalin three times per week intravenously for 6 weeks. The primary end point was change from baseline in the Worst Itching Intensity Numerical Rating Scale (NRS; 0 to 10; higher scores indicate more severe itching) score at week 4. RESULTS: A total of 230 patients were screened, of whom 178 were randomly assigned to receive placebo (n=89) or difelikefalin (n=89). The change from baseline in the weekly adjusted mean NRS score (95% confidence interval) at week 4 in the placebo and difelikefalin groups was −1.09 (−1.47 to −0.70) and −2.06 (−2.45 to −1.66), respectively. The difference between the groups was −0.97 (−1.52 to −0.42), demonstrating that difelikefalin was superior to placebo (P<0.001). Prespecified secondary quality-of-life end points showed consistent improvement associated with difelikefalin. The incidence of treatment-related adverse events in the placebo and difelikefalin groups was 3 of 89 patients (3%) and 13 of 89 patients (15%), respectively, of which the majority in the difelikefalin group were gastrointestinal (e.g., constipation and abdominal discomfort). CONCLUSIONS: Intravenous difelikefalin reduced itching and improved quality of life in patients with moderate to severe pruritus who were undergoing maintenance hemodialysis. (Funded by Kissei Pharmaceutical Co., Ltd.; ClinicalTrials.gov number, NCT04711603.)

Safety and effectiveness of HSK21542 for hemodialysis patients: a multiple ascending dose study

Background: HSK21542, a novel selective peripherally-restricted κ-opioid receptor agonist has been proven to be a safe and effective analgesic and antipruritic drug in both in vitro and in vivo studies. We aimed to evaluate its safety, pharmacokinetics and efficacy in hemodialysis patients over a 1-week treatment period, and to establish the optimal dosage for a further 12-week stage 2 trial. Methods: In this multiple ascending dose study, hemodialysis patients were randomly assigned to receive HSK21542 (0.05-0.80 μg/kg), or a placebo three times within 2.5 h at the end of each dialysis session for 1 week. Safety evaluations included reports of treatment-emergent adverse events (TEAEs); pharmacokinetics and efficacy outcomes were also assessed. Results: Among the 44 screened patients, 41 were enrolled and completed the trial. The overall incidence of TEAEs was higher in the HSK21542 group compared to the placebo group, with an incidence of 75.0%, 50.0%, 75.0%, and 88.9% in the range of 0.05-0.80 μg/kg. All TEAEs were grade 1 or 2 in severity. HSK21542 exhibited linear pharmacokinetics characteristics within the dose range 0.05-0.80 μg/kg, without drug accumulation after multiple-doses. Compared to the placebo, a significant decrease of the weekly mean Worst Itching Intensity Numerical Rating Scale was found in the HSK21542-0.30 μg/kg group (p = 0.046), but without significant improvement in the Skindex-16 score. Conclusion: HSK21542 was well tolerated in the dose range 0.05-0.80 μg/kg in hemodialysis patients. HSK21542-0.3 μg/kg exhibited promising efficacy in patients with moderate to severe pruritus and warrants a further Stage 2 trial. Clinical Trial Registration: https://clinicaltrials.gov/, identifier NCT04470154.

Kappa opioid agonists in the treatment of itch: just scratching the surface?

Chronic pruritus is a debilitating condition affecting 23-44 million Americans. Recently, kappa opioid agonists (KOAs) have emerged as a novel class of potent antipruritic agents. In 2021, the Food and Drug Administration approved difelikefalin (Korsuva) for the treatment of moderate-to-severe pruritus associated with chronic kidney disease in adults undergoing hemodialysis. Difelikefalin is a potent, peripherally restricted KOA that is intravenously available. Although promising, difelikefalin is currently available as an intravenous composition only, limiting the scope of use. Oral formulations of difelikefalin did not meet the primary endpoint criteria in recent phase 2 clinical trials; however, additional clinical studies are ongoing. The future for KOAs in the treatment of pruritus is encouraging. Orally active pathway-biased KOAs, such as triazole 1.1, may serve as viable alternatives with broader applications. Extended-release compositions, such as the TP-2021 ProNeura subdermal implant, may circumvent the pharmacokinetic issues associated with peptide-based KOAs. Lastly, dual-acting kappa opioid receptor agonist/mu opioid receptor antagonists are orally bioavailable and may be useful in the treatment of various forms of chronic itch. In this review, we summarize the results of KOAs in clinical and preclinical trials and discuss future directions of drug development.

Difelikefalin: A New κ-Opioid Receptor Agonist for the Treatment of Hemodialysis-Dependent Chronic Kidney Disease-Associated Pruritus

OBJECTIVE

To review data for difelikefalin (Korsuva) intravenous solution for management of moderate-to-severe pruritus in hemodialysis (HD) patients.

DATA SOURCES

Literature search of PubMed (January 1946-May 2022) and SCOPUS (January 1946-May 2022) was performed using the terms: Korsuva, CR845, and difelikefalin. Additional information sources include ClinicalTrials.gov, prescribing information, meeting posters, and references of identified articles.

STUDY SELECTION AND DATA EXTRACTION

Clinical trials and articles evaluating difelikefalin for chronic kidney disease-associated pruritis (CKD-aP) in HD patients.

DATA SYNTHESIS

Difelikefalin is a peripherally acting κ-opioid receptor agonist with antipruritic effects for HD patients with moderate-to-severe CKD-aP. A phase 3 study showed significant improvement of patient itch intensity and itch-related quality of life (QOL) when compared with placebo. More patients had decreased pruritus on the 24-hour Worst Itch Intensity Numerical Rating Scale with difelikefalin (49.1%) compared with placebo (27.9%, P < 0.001). A positive effect was seen with or without use of additional antipruritic agents. Common adverse events include diarrhea, dizziness, and vomiting; there were no signs of physical dependence or centrally acting opioid effects (euphoria, hallucinations).

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Difelikefalin reduced itch intensity and improved QOL for patients with CKD-aP. Whether the benefit is continued long-term as well as how it compares with other effective agents is currently unknown.

CONCLUSION

Difelikefalin is the only Food and Drug Administration-approved treatment for moderate-to-severe CKD-aP with additional research into its benefit in this and other types of pruritus ongoing.

Endogenous Opioid Imbalance as a Potential Factor Involved in the Pathogenesis of Chronic Kidney Disease-Associated Pruritus in Dialysis Patients

Chronic pruritus is one of the most common symptoms of dermatological diseases. It may occur in the course of other disorders, such as kidney disease. Chronic kidney disease-associated pruritus (CKD-aP) most often affects people with end-stage renal disease. The etiology of this condition is still not fully understood, but researchers are currently focusing on a thorough analysis of the association between disturbed opioid balance and increased neuronal signaling leading to pruritus. The aim of this study is to assess the concentration of endogenous opioids in dialysis patients with and without pruritus and in the control group, and to determine the correlation between the concentration of these substances and the occurrence and severity of itching. The study involved 126 dialysis patients and 50 healthy controls. Patients were divided into groups with pruritus (n = 62) and without pruritus (n = 64). The severity of pruritus was assessed using the NRS scale. The concentration of endogenous opioids was determined using the ELISA. The concentration of met-enkephalin was higher in the group of patients with pruritus compared to the control group. Moreover, significantly lower levels of β-endorphin and dynorphin A were observed in the group of dialysis patients compared to the control group. In addition, a statistically significant difference was seen between the β-endorphin concentration in the group of dialysis patients with pruritus compared to the group without pruritus. The ratio of β-endorphin/dynorphin A concentrations was significantly lower in the group of patients with pruritus compared to patients without pruritus and the control group. No correlations were found between serum level of studied opioids and the severity of pruritus. The concentrations of the studied opioids did not correlate with the severity of pruritus. Observed opioid imbalance may affect the occurrence of CKD-aP in dialysis patients, but a thorough understanding of the mechanism of action of these substances in the sensation of pruritus is necessary to assess the possibility of finding a new therapeutic target.

How to get rid of itching

Itch is an unpleasant sensation arising from a variety of dermatologic, neuropathic, systemic, and psychogenic etiologies. Various itch pathways are implicated according to the underlying etiology. A variety of pruritogens, or itch mediators, as well as receptors have been identified and provide potential therapeutic targets. Recent research has primarily focused on targeting inflammatory cytokines and Janus kinase signaling, protease-activated receptors, substance P and neurokinin, transient receptor potential-vanilloid ion channels, Mas-related G-protein-coupled receptors (MRGPRX2 and MRGPRX4), the endogenous opioid and cannabinoid balance, and phosphodiesterase 4. Periostin, a newly identified pruritogen, should be further explored with clinical trials. Drugs targeting neural sensitization including the gabergic system and P2X3 are other potential drugs for chronic itch. There is a need for more targeted therapies to improve clinical outcomes and reduce side effects.

Nouvelles thérapies dans la prise en charge du patient avec maladie rénale chronique souffrant de prurit : une revue de la littérature New therapies in the management of chronic kidney disease associated pruritus

Chronic Kidney Disease associated Pruritus (CKD-aP) is a well-established and frequent complication observed in patient with CKD, especially in dialysis patients. However, the management of CKD-aP remains a challenge as the pathophysiology and research studies are too small. Finally, there are a few proposed treatment options with significant clinical benefits. This general review will summarize all the available treatments for the CKD-aP and will highlight the clinical efficacy and limits of the current drugs. Notably, we will focus on the implication of the opioid receptor in the pathophysiology of the CKD-aP and the recently Kappa opioid receptor agonist. © 2022 Published by Elsevier Masson SAS on behalf of Société francophone de néphrologie, dialyse et transplantation.

Difelikefalin in the Treatment of Chronic Kidney Disease-Associated Pruritus: A Systematic Review

Chronic kidney disease-associated pruritus (CKD-aP) is a chronic condition that significantly reduces the quality of life of patients with end-stage renal disease. The etiology is not fully understood, but imbalance in the activity of the opioid pathways, including downregulation of the kappa-opioid receptor, may contribute to itching sensation. Difelikefalin is a selective, peripherally acting kappa-opioid receptor (KOR) agonist. Recently, difelikefalin has been approved as a first drug for the treatment of pruritus associated with chronic kidney disease (CKD) in adult hemodialysis patients. A systematic review of currently available clinical trials was performed to assess the efficacy and safety of difelikefalin in patients with uremic pruritus. A literature review was conducted in May 2022 based on the PRISMA 2020 guidelines. The analyzed clinical trials showed that difelikefalin was effective in reducing pruritus in patients as assessed by the Worst Itching Intensity Numerical Rating Scale. Improvement in quality of life assessed on the basis of the Skindex score and the 5-D itch scale was also noticed. The most commonly reported side effects were mild and included nausea, vomiting, dizziness, and diarrhea. Due to its proven efficacy and good safety profile, difelikefalin is a promising drug for the treatment of pruritus in patients with chronic kidney disease.