Efficacy and Safety of Abrocitinib in Prurigo Nodularis and Chronic Pruritus of Unknown Origin: A Nonrandomized Controlled Trial.

Importance: Prurigo nodularis (PN) and chronic pruritus of unknown origin (CPUO) are chronic pruritic diseases that dramatically impair quality of life, but therapeutic options are limited. Abrocitinib, a Janus kinase 1 inhibitor, represents a promising therapy for both conditions. Objective: To assess the efficacy and safety of 200-mg oral abrocitinib administered once daily in adults with moderate to severe PN or CPUO. Design, Setting, and Participants: This phase 2, open-label, nonrandomized controlled trial conducted between September 2021 and July 2022 took place at a single center in the US. A total of 25 adult patients with moderate to severe PN or CPUO were screened. Ten patients with PN and 10 patients with CPUO were enrolled. All 20 patients completed the 12-week treatment period, 18 of whom completed the 4-week follow-up period. Intervention: Abrocitinib, 200 mg, by mouth once daily for 12 weeks. Main Outcomes and Measures: The primary efficacy end point was the percent change in weekly Peak Pruritus Numerical Rating Scale (PP-NRS) scores from baseline to week 12. Key secondary end points included the percentage of patients achieving at least a 4-point reduction in weekly PP-NRS score from baseline to week 12 and the percent change in Dermatology Life Quality Index (DLQI) scores. Results: A total of 10 patients with PN (mean [SD] age, 58.6 [13.1] years; all were female) and 10 patients with CPUO (mean [SD] age, 70.7 [5.6] years; 2 were female) enrolled in the study. The mean (SD) baseline PP-NRS score was 9.2 (1.0) for PN and 8.2 (1.2) for CPUO. PP-NRS scores decreased by 78.3% in PN (95% CI, -118.5 to -38.1; P < .001) and 53.7% in CPUO (95% CI, -98.8 to -8.6; P = .01) by week 12. From baseline to week 12, 8 of 10 patients with PN and 6 of 10 patients with CPUO achieved at least a 4-point improvement on the PP-NRS. Both groups experienced significant improvement in quality of life as demonstrated by percent change in DLQI scores (PN: -53.2% [95% CI, -75.3% to -31.1%]; P = .002; CPUO: -49.0% [95% CI, -89.6% to -8.0%]; P = .02). The most common adverse event among patients was acneiform eruption in 2 of 20 patients (10%). No serious adverse events occurred. Conclusions and Relevance: The results of this nonrandomized controlled trial suggest that abrocitinib monotherapy may be effective and tolerated well in adults with PN or CPUO. Randomized, double-blind, placebo-controlled trials are warranted to validate these findings. Trial Registration: ClinicalTrials.gov Identifier: NCT05038982.

Increased cardiovascular risks and mortality in prurigo nodularis: a global cohort study.

BACKGROUND: Prurigo nodularis (PN) presents with intensely itchy hard nodules. Despite being limited to the skin, PN was noted to be associated with systemic diseases including diabetes and chronic renal failure. In previous smaller retrospective studies, several cardiac and vascular diseases were found more frequently in patients with PN. However, small cohort sizes, partially discrepant outcomes, missing data, and incomplete risk assessment limit these findings. METHODS: Electronic health records (EHR)s of 64,801 patients (59.44% females) with PN and an equal sized propensity-matched control group were retrieved. In these cohorts, the risks to develop cardiac and vascular diseases and mortality following the diagnosis of PN were determined. Sub-analyses included stratification for sex, ethnicity, and treatments. FINDINGS: PN was associated with a higher risk for a broad range of acute cardiac events including heart failure and myocardial infarction. For example, the hazard ratio of myocardial infarction was 1.11 (95%-CI: 1.041-1.184, p = 0.0015) following PN diagnosis. Also, all-cause mortality was higher in patients with PN. Further, chronic vascular as well as structural heart diseases, e.g., peripheral arterial disease, chronic ischaemic heart disease and valval disorders were found more frequently following a PN diagnosis. Risks were more pronounced in white and female patients. Having established an increased risk for death and cardiovascular disease, we next addressed if dupilumab that has been recently licenced for use in this indication can modulate these risks. The risk of death but not of any cardiovascular disease was slightly reduced in patients with PN treated with dupilumab as opposed to those treated with systemic therapies other than dupilumab. The study is limited by retrospective data collection and reliance on ICD10-disease classification. INTERPRETATION: PN is associated with higher mortality and an increased risk for the development of a wide range of cardiac and vascular diseases. Health care professionals should take this into account when managing patients with PN. FUNDING: This work was supported by the University of Lübeck, the Deutsche Forschungsgemeinschaft and the State of Schleswig-Holstein.

Estimating meaningful change thresholds for Skin Pain-Numeric Rating Scale, Sleep-Numeric Rating Scale and Dermatology Life Quality Index in patients with prurigo nodularis.

BACKGROUND: Prurigo nodularis (PN) is characterized by intensely itchy nodules/lesions and skin pain, which can have a substantial impact on health-related quality of life (HRQoL). Treatment benefits on such symptoms and impacts are best assessed in trials using patient-reported outcome (PROs) instruments such as Skin Pain Numerical Rating Scale (NRS), Sleep-NRS and Dermatology Life Quality Index (DLQI). However, no guidance exists for interpreting meaningful changes in scores using these PROs in patients with PN. OBJECTIVES: The main objective was to derive within-patient (responder definition) and between-group improvement thresholds for interpreting Skin Pain-NRS, Sleep-NRS and DLQI total scores in patients with PN. The measurement properties of the three PROs were also evaluated. METHODS: Intention-to-treat (ITT), blinded and pooled data were used from the Phase 3 PRIME (NCT04183335) and PRIME2 (NCT04202679) studies evaluating the efficacy of dupilumab in adult patients with PN. Anchor- and distribution-based methods were applied to derive responder definition and between-group thresholds for Skin Pain-NRS, Sleep-NRS and DLQI. Data were additionally used to examine the instrument measurement properties, including reliability, validity and responsiveness. RESULTS: A total of 311 patients (mean age 49.5 years, 65.3% female) were included in the pooled ITT population. The within-patient improvement threshold for Skin Pain-NRS was estimated as 4.0 points, 2.0 points for Sleep-NRS and 9.0 points for DLQI total score. A 1.5-point improvement in Skin Pain-NRS scores, 1.0-point in Sleep-NRS and 4.0-point in DLQI indicated a between-group meaningful change. Adequate to good psychometric properties were demonstrated for all three instruments. CONCLUSIONS: The results of this study can aid interpretation of Skin Pain-NRS, Sleep-NRS and DLQI scores in patients with PN in both clinical trials and clinical practice to better understand and treat PN-related skin pain and the impact of PN on sleep quality and HRQoL.

A systematic review of interleukin-31 inhibitors in the treatment of prurigo nodularis.

BACKGROUND: Prurigo nodularis (PN) is a neuroimmunological skin disease. Severe itching is the most challenging symptom which affects patients' quality of life. T helper 2-derived cytokines, such as interleukin-31 and oncostatin M (OSM), play a crucial role in PN pathogenesis. Nemolizumab and vixarelimab are two biologics acting as IL-31 inhibitors. Vixarelimab also suppresses the OSM activity. This systematic review evaluates the efficacy and safety of nemolizumab and vixarelimab in PN management. METHODS: A systematic search was conducted in PubMed/Medline, Ovid Embase, and Web of Science up to September 17th, 2023. Clinical trials and cohort studies published in English were included. RESULTS: Among a total of 96 relevant records, five were included. The results of four studies with 452 patients using nemolizumab showed that a significantly higher percentage of patients treated with nemolizumab demonstrated a reduction in peak pruritus numerical rating scale (PP-NRS) and investigator's global assessment along with improved sleep disturbance (SD) and quality of life than the placebo group. Moreover, one study administered vixarelimab to 49 PN patients, and their finding illustrated a higher rate of subjects who received vixarelimab experienced ≥ 4-point diminution in worst itch NRS, visual analog scale, healing of representative lesions, and SD quality compared to the placebo group. CONCLUSIONS: IL-31 inhibitors suggest distinct advantages in improving pruritus, sleep quality, and overall quality of life in subjects with moderate-to-severe PN. Further clinical studies are recommended to compare the effectiveness of these biologics to other therapeutic choices.

Actinic conjunctivitis and its relationship with prurigo in an indigenous population from the Highlands of Chiapas, Mexico.

PURPOSE: Actinic conjunctivitis (AC), along with cheilitis (AChe), is part of the clinical spectrum of actinic prurigo (AP), a rare photo dermatosis that affects high-risk populations. We analyzed the clinical manifestations and onset of actinic conjunctivitis (AC), and its relationship with prurigo (AP) in a susceptible population. METHODS: This prospective observational cohort study was performed on Indigenous populations from the highlands of Chiapas, Mexico. Thorough dermatological and ophthalmological examinations were performed in patients attending a primary health care center. The clinical features, labor and environmental factors, onset timing, and clinical staging of AC and AP were analyzed. RESULTS: Of the 2913 patients studied, 54 patients (108 eyes) (1.8%) had AC, and 14 patients (25.9%) had AP. The mean age at diagnosis was 36.18 ± 18.52 years (6-70 years). The mean residential altitude was 1884 ± 434.2 m above sea level. Mean self-reported sun exposure was 5.14 ± 3.1 h a day (0.5-12 h). A total of 90.7% reported exposure to biomass fuels during cooking, and 50% to farm animals. AC was the sole manifestation in 70% of the cases. All patients had nasal and temporal photo-exposed conjunctiva. Among the eyes, 12.9% were classified as stage-1, 64.8% as stage-2, and 22.2% stage-3. A total of 83.3% of the patients had hyperpigmented lesions, and 35.1% had evaporative dry eye disease. CONCLUSIONS: AC may be the initial or sole manifestation of AP. Most AC cases (87%) were initially observed at the advanced stages of the disease. Although solar exposure was not associated with late AC stages, a positive association was found with farm animal exposure. Evaporative dry eye associated with meibomian gland dysfunction has not been previously reported in patients with AC.

INDIVIDUAL ARTICLE: Prurigo Nodularis: Current Clinicopathologic Overview and Psychodermatological Perspectives.

Prurigo nodularis (PN) is a quintessential neurocutaneous condition characterized by neural sensitization and intractable itch leading to intense scratching. This causes the formation of nodules with epidermal thickening and further release of pro-inflammatory mediators that recruit immune cells and increase dermal nerve proliferation and hypertrophy perpetuating the itch-scratch cycle. Those with PN have a significant quality-of-life (QoL) burden due to itch, anxiety, and sleep disturbance. In addition, PN exhibits psychiatric comorbidities that affect mental wellbeing such as depression, mood disorders, and substance abuse. This paper serves as an overview of the clinicopathologic aspects of PN, the burden of PN on QoL, and the psychodermatological aspects of the disease state.  J Drugs Dermatol. 2023;22:12(Suppl 2):s6-11.

INDIVIDUAL ARTICLE: Management of Prurigo Nodularis.

BACKGROUND: Prurigo nodularis (PN) is a chronic disease characterized by intense pruritus and nodular lesions associated with reduced quality of life. Until recently, no US Food and Drug Administration (FDA)-approved therapies have been available for the management of PN. Treatment regimens have been highly variable and clinical management guidelines are lacking overall; formal treatment guidelines do not exist within the US. In 2022, dupilumab became the first FDA-approved medication for PN. Multiple novel agents that target the neuroimmune underpinnings of the disease are currently in development and show promise for this challenging disorder. OBJECTIVE: To review current treatments and emerging therapies for effective management of patients with PN. METHODS: We reviewed publications on PN management identified from PubMed, Embase, Web of Science, and the Cochrane Library. We also included publicly available data on clinical trials for PN therapies reported on the US National Library of Medicine ClinicalTrials.gov, the International Conference on Harmonisation-Good Clinical Practice (ICH-GCP) Database, and the European Clinical Trials (EudraCT) Database. RESULTS: The recommended management of PN begins with an assessment of disease severity, including disease burden and pruritus intensity, and evaluation of comorbid medical disorders. Treatment goals include resolution of itch, improvement in nodules or cutaneous lesions, and improvement in quality of life. Therapies should be selected based on a patient’s clinical presentation and comorbidities. Treatment should simultaneously address the neural and immunologic components of PN. Combination therapy, particularly with conventional agents, may be beneficial. LIMITATIONS: Data on most conventional PN treatments are limited to anecdotal reports, small clinical trials, or expert consensus recommendations. No head-to-head comparative trials have evaluated the relative efficacy of conventional and/or emerging agents, or combination therapy. CONCLUSION: An effective treatment approach for patients with PN should reduce pruritus, allow nodular lesions to heal, and improve individual quality of life. The treatment landscape for PN is rapidly evolving with one FDA-approved agent and several new promising therapies on the horizon. J Drugs Dermatol. 2023;22:12(Suppl 2):s15-22.

Phase 3 Trial of Nemolizumab in Patients with Prurigo Nodularis.

BACKGROUND: Prurigo nodularis is a chronic, debilitating, and severely pruritic neuroimmunologic skin disease. Nemolizumab, an interleukin-31 receptor alpha antagonist, down-regulates key pathways in the pathogenesis of prurigo nodularis. METHODS: In this phase 3, double-blind, multicenter, randomized trial, we assigned adults with moderate-to-severe prurigo nodularis to receive an initial 60-mg dose of nemolizumab followed by subcutaneous injections of 30 mg or 60 mg (depending on baseline weight) every 4 weeks for 16 weeks or matching placebo. The primary end points were an itch response (a reduction of ≥4 points on the Peak Pruritus Numerical Rating Scale [PP-NRS; scores range from 0 to 10, with higher scores indicating more severe itch]) and an Investigator's Global Assessment (IGA) response (a score of 0 [clear] or 1 [almost clear] on the IGA [scores range from 0 to 4] and a reduction from baseline to week 16 of ≥2 points). There were five key secondary end points. RESULTS: A total of 274 patients underwent randomization; 183 were assigned to the nemolizumab group, and 91 to the placebo group. Treatment efficacy was shown with respect to both primary end points at week 16; a greater percentage of patients in the nemolizumab group than in the placebo group had an itch response (56.3% vs. 20.9%; strata-adjusted difference, 37.4 percentage points; 95% confidence interval [CI], 26.3 to 48.5), and a greater percentage in the nemolizumab group had an IGA response (37.7% vs. 11.0%; strata-adjusted difference, 28.5 percentage points; 95% CI, 18.8 to 38.2) (P<0.001 for both comparisons). Benefits were observed for the five key secondary end points: itch response at week 4 (41.0% vs. 7.7%), PP-NRS score of less than 2 at week 4 (19.7% vs. 2.2%) and week 16 (35.0% vs. 7.7%), and an improvement of 4 or more points on the sleep disturbance numerical rating scale (range, 0 [no sleep loss] to 10 [unable to sleep at all]) at week 4 (37.2% vs. 9.9%) and week 16 (51.9% vs. 20.9%) (P<0.001 for all comparisons). The most common individual adverse events were headache (6.6% vs. 4.4%) and atopic dermatitis (5.5% vs. 0%). CONCLUSIONS: Nemolizumab monotherapy significantly reduced the signs and symptoms of prurigo nodularis. (Funded by Galderma; ClinicalTrials.gov number, NCT04501679; EudraCT number, 2019-004789-17.).

Modulation of Neuroimmune and Epithelial Dysregulation in Patients With Moderate to Severe Prurigo Nodularis Treated With Nemolizumab.

Importance: Prurigo nodularis (PN) is a debilitating skin disease characterized by intense pruritus and hyperkeratotic skin nodules. Nemolizumab, a monoclonal antibody targeting interleukin 31 receptor α, is a promising novel therapy for the treatment of moderate to severe PN. The biological mechanisms by which nemolizumab promotes improvement of itch and skin lesions in PN are unknown. Objective: To characterize changes in plasma protein biomarkers associated with clinical response to nemolizumab in patients with PN. Design, Setting, and Participants: This multicenter cohort study included patients recruited from Austria, France, Germany, Poland, and the US from a phase 2 clinical trial. Adults diagnosed with moderate to severe PN with severe pruritus for at least 6 months were included in the original trial. Patients in the nemolizumab group were included in the present study if they achieved at least a 4-point decrease in the Peak Pruritus Numerical Rating Scale (PP-NRS) from baseline to week 12 during nemolizumab treatment. Placebo controls did not experience a 4-point decrease in PP-NRS. Mass spectrometry with tandem mass tags to enrich skin-specific protein detection was used to characterize changes in plasma protein expression in nemolizumab and placebo groups. Data were collected from November 2, 2017, to September 26, 2018, and analyzed from December 6, 2019, to April 8, 2022. Intervention: As part of the clinical trial, patients were treated with 3 doses of nemolizumab or placebo at 0, 4, and 8 weeks. Main Outcomes and Measures: Changes in plasma and epidermal protein expression in nemolizumab-treated patients compared with the placebo group at 0, 4, and 12 weeks. Results: Among the 38 patients included in the analysis (22 women and 16 men; mean [SD] age, 55.8 [15.8] years), enrichment analysis of canonical pathways, biological functions, and upstream regulators showed downregulation of terms involving inflammation (IL-6, acute-phase response, signal transducer and activator of transcription 3, and interferon γ), neural processes (synaptogenesis signaling and neuritogenesis), tissue remodeling and fibrosis (transforming growth factor ß1 and endothelin-1), and epidermal differentiation (epithelial mesenchymal transition) in the plasma of nemolizumab group. Conclusions and Relevance: In this cohort study, differences between nemolizumab and placebo groups included modulation of inflammatory signaling, neural development, and epithelial differentiation, suggesting a promising potential approach for clinical management of PN.

Resolution of a Focal Pruritic Rash Following Neurosurgical Decompression in an Adolescent With Chiari I and Syringomyelia.

BACKGROUND: Chiari I malformation (Chiari I) is defined by the downward displacement of one or both cerebellar tonsils below the foramen magnum of the skull with crowding altering cerebrospinal fluid flow. It can be associated with the development of a fluid-filled cavity within the spinal cord, syringomyelia. Neurological deficits or symptoms can occur at the level of anatomic involvement of syringomyelia. CASE PRESENTATION: A young man presented to dermatology clinic for evaluation of a pruritic rash. Recognizing a unique left "cape-like" distribution of neuropathic itch leading to prurigo nodularis, he was referred for further evaluation by neurology in the local emergency department. After additional history and neurological exam, a magnetic resonance imaging confirmed Chiari I with an associated syringobulbia and a syrinx extending to T10/11 of the spinal cord. Anteriorly the syrinx extended into the left parenchyma of his spinal cord involving the dorsal horn, a lesion explaining his neuropathic itch. The sensation of itch and rash resolved after posterior fossa craniectomy and C1 laminectomy with duraplasty. CONCLUSION: Neuropathic itch, in addition to pain, can be a symptom of Chiari I with syringomyelia. Focal pruritus without an obvious cutaneous trigger should prompt providers to consider a central neurological pathology. While many patients with Chiari I are asymptomatic, the presence of neurological deficits and syringomyelia, are indications for neurosurgical evaluation.

Endotoxin concentration and persistent eczema in early childhood.

Although endotoxin concentration in the environment is negatively associated with atopic dermatitis (AD) onset in early childhood, the association between endotoxin concentration in the environment and eczema resolution in children with preexisting eczema is unclear. The aim of this study was to evaluate the association between endotoxin concentration in house dust and eczema persistence in young children. The authors used data from children participating in JECS (Japan Environment and Children's Study). In children who had AD or AD-like lesions at the age of 1 year, the authors investigated the association between the prevalence of eczema at the age of 3 years and endotoxin concentration (categorized by quartiles) in the dust on children's mattresses at the ages of 1.5 and 3 years. This study included 605 children. Eczema was significantly less prevalent among children whose mattresses were in the second and third quartiles of endotoxin concentration when they were 18 months old than among children whose mattresses were in the first quartile (adjusted odds ratio, 0.57 [95% confidence interval, 0.35-0.93] and adjusted odds ratio, 0.49 [95% confidence interval, 0.29-0.83], respectively). Moreover, of the children with eczema at age 3 years, those whose mattresses had endotoxin concentrations in the first quartile had significantly worse sleep disturbance caused by itchy rash (>1 time per week) than did those whose mattresses were in the third and fourth quartiles (20.0% vs 3.3% and 3.7%, both p values < 0.01). The findings indicate that low endotoxin exposure is associated with a higher prevalence of persistent eczema during early childhood.

Impact of Chronic Kidney Disease Severity on the Risk of Prurigo Nodularis: A Population-Based Cohort Study.

While dialysis is linked with prurigo nodularis, little is known about the impact of non-dialysis chronic kidney disease on prurigo nodularis. The influence of chronic kidney disease on development of prurigo nodularis was measured using the Korean National Health Insurance and National Health Screening Program data, identifying 17,295,576 individuals without prior prurigo nodularis. Chronic kidney disease severity was determined by the estimated glomerular filtration rate (in ml/min/1.73 m2) calculated from serum creatinine, and proteinuria detected with urine dipstick. Prurigo nodularis incidence during follow-up was determined. Over a median follow-up period of 9.72 years, 58,599 individuals developed prurigo nodularis, with an incidence rate of 3.59 per 10,000 person-years. Among different variables, estimated glomerular filtration rate was the strongest risk factor for prurigo nodularis. Compared with estimated glomerular filtration rate ≥ 90, estimat-ed glomerular filtration rate 15-29 (hazard ratio 1.31, 95% confidence interval 1.05-1.62) and end-stage renal disease (hazard ratio 1.46, 95% confidence interval 1.25-1.69) were associated with higher risks. The presence of proteinuria independently increased the risk of prurigo nodularis, increased risks associated with estimated glomerular filtration rate 15-29 and end-stage renal disease, and caused risk associated with estimated glomerular filtration rate 30-59 to become significant. With differential impact of chronic kidney disease severity on the risk of prurigo nodularis, preservation of renal function would potentially translate into lower risk of prurigo nodularis.