Phase 3 Trial of Nemolizumab in Patients with Prurigo Nodularis

Pathophysiology of Prurigo Nodularis: Neuroimmune Dysregulation and the Role of Type 2 Inflammation

Prurigo nodularis (PN) is a chronic, inflammatory skin condition characterized by multiple, intensely pruritic, distinctive nodular lesions. Subsequent scratching can further intensify the pruritus, culminating in a self-reinforcing itch-scratch cycle, which drives lesion development. The latest data indicate dysregulation of the neuroimmune axis in PN pathogenesis, including the involvement of sensory neurons, key effector immune cells, proinflammatory cytokines, dermal fibroblasts, and pruritogens. In this review, we highlight evidence supporting the role of type 2 immune axis dysregulation in driving the clinical presentation of PN and discuss how related signaling pathways may offer effective therapeutic targets to control PN signs and symptoms.

The role of nemolizumab in the treatment of atopic dermatitis for the adult population

Atopic dermatitis (AD) often requires long-term treatment that may be associated with adverse effects. This review aims to characterize nemolizumab as a treatment for AD in adults. A literature search was performed to assess nemolizumab's role in moderate-to-severe AD in adults. Currently, clinical trials are being conducted to evaluate the clinical efficacy, safety profile and optimal dosing of nemolizumab for adults with moderate-to-severe AD. The most common adverse effects include nasopharyngitis, AD exacerbation and increased blood creatinine phosphokinase. Recent data from clinical trials suggest nemolizumab may be an acceptable treatment in adults with moderate-to-severe AD.

Abrocitinib Monotherapy for Refractory Prurigo Nodularis: Report of Two Successful Cases

Prurigo nodularis (PN) is a debilitating chronic neuroimmunologic skin condition due to the intense pruritus and difficult to treat. The pruritogenic cytokines, particularly IL-4, IL-13, IL-22, IL-31, and oncostatin M (OSM), play a crucial role in the pathogenesis of PN, potentially involving the JAK1-STAT pathway. An oral JAK1 inhibitor, abrocitinib, is presently undergoing Phase 2 trials for the treatment of PN. We evaluated the efficacy of abrocitinib at a daily dosage of 100 mg in treating two patients with PN affecting both lower limbs: a 50-year-old male with a 16-year disease history and a 38-year-old female with over three years of disease history, both of whom had failed to respond to multiple conventional treatments. Both patients responded rapidly after one week of treatment and exhibited a marked improvement. Following eight weeks of therapy, near-complete resolution of both pruritus and lesions was achieved, and no adverse effects were reported. Additionally, there were no reported side effects during the initial four months of continued treatment. Abrocitinib is an effective targeted therapy for PN, offering a promising new option for refractory patients.

Nemolizumab with concomitant topical therapy in adolescents and adults with moderate-to-severe atopic dermatitis (ARCADIA 1 and ARCADIA 2): results from two replicate, double-blind, randomised controlled phase 3 trials

BACKGROUND

Nemolizumab, an interleukin (IL)-31 receptor subunit α antagonist, inhibits the IL-31 pathway of itch and skin inflammation in atopic dermatitis. Two international phase 3 studies were done to assess the efficacy and safety of nemolizumab in atopic dermatitis. In this Article we report results for the 16-week initial treatment period of both trials.

METHODS

ARCADIA 1 and ARCADIA 2 were identical 48-week randomised, double-blind, placebo-controlled phase 3 trials in adult and adolescent participants (aged ≥12 years) with moderate-to-severe atopic dermatitis, associated pruritus, and inadequate response to topical steroids. Participants were enrolled from 281 clinics, hospitals, and academic centres in 22 countries across both trials, and were randomly assigned (2:1) to receive nemolizumab 30 mg subcutaneously (baseline loading dose 60 mg) or matching placebo once every 4 weeks with background topical corticosteroids (TCS) with or without topical calcineurin inhibitors (TCI; ie, TCS-TCI background treatment). Randomisation was done via interactive response technology and stratified by baseline disease and pruritus severity. Study staff and participants were masked throughout the study, with outcome assessors masked until database lock. Coprimary endpoints at week 16 post-baseline were Investigator's Global Assessment (IGA) success (score of 0 [clear skin] or 1 [almost clear skin] with a ≥2-point improvement from baseline) and at least 75% improvement in Eczema Area and Severity Index score from baseline (EASI-75 response). Outcome rates were compared between groups with the Cochran-Mantel-Haenszel test adjusting for randomisation strata. The key secondary endpoints were the proportion of participants with Peak Pruritus Numerical Rating Scale (PP-NRS) score improvement of at least 4 points at weeks 1, 2, 4, and 16; PP-NRS score below 2 at weeks 4 and 16; Sleep Disturbance Numerical Rating Scale score improvement of at least 4 points at week 16; EASI-75 response plus PP-NRS score improvement of at least 4 points at week 16; and IGA success plus PP-NRS score improvement of at least 4 points at week 16. Efficacy analyses were done on an intention-to-treat basis; safety analyses included all participants who received one dose of nemolizumab or placebo. Both studies are completed (ClinicalTrials.gov: ARCADIA 1, NCT03985943 and ARCADIA 2, NCT03989349).

FINDINGS

Between Aug 9, 2019, and Nov 2, 2022, 1728 participants were enrolled across both trials: 1142 were allocated to nemolizumab plus TCS-TCI (620 in ARCADIA 1 and 522 in ARCADIA 2) and 586 to placebo plus TCS-TCI (321 in ARCADIA 1 and 265 in ARCADIA 2). ARCADIA 1 included 500 (53%) male participants and 441 (47%) female participants, and ARCADIA 2 included 381 (48%) male participants and 406 (52%) female participants. Mean age ranged from 33·3 (SD 15·6) years to 35·2 (17·0) years across the treatment groups. Both trials met the coprimary endpoints; at week 16, a greater proportion of participants receiving nemolizumab plus TCS-TCI versus placebo plus TCS-TCI had IGA success (ARCADIA 1: 221 [36%] of 620 vs 79 [25%] of 321, adjusted percentage difference 11·5% [97·5% CI 4·7-18·3], p=0·0003; ARCADIA 2: 197 [38%] of 522 vs 69 [26%] of 265, adjusted difference 12·2% [4·6-19·8], p=0·0006) and an EASI-75 response (ARCADIA 1: 270 [44%] vs 93 [29%], adjusted difference 14·9% [7·8-22·0], p<0·0001; ARCADIA 2: 220 [42%] vs 80 [30%], adjusted difference 12·5% [4·6-20·3], p=0·0006). Significant benefits were observed with nemolizumab for all key secondary endpoints including improvement in itch, as early as week 1, and sleep improvement by week 16. The safety profile was similar between nemolizumab plus TCS-TCI and placebo plus TCS-TCI. In the safety sets, 306 (50%) of 616 participants (ARCADIA 1) and 215 (41%) of 519 participants (ARCADIA 2) who received nemolizumab plus TCS-TCI had at least one treatment-emergent adverse event (serious treatment-emergent adverse events in six [1%] and 13 [3%], respectively); and 146 (45%) of 321 (ARCADIA 1) and 117 (44%) of 263 (ARCADIA 2) who received placebo plus TCS-TCI had at least one treatment-emergent adverse event (serious treatment-emergent adverse events in four [1%] and three [1%], respectively). Ten serious treatment-emergent adverse events possibly related to nemolizumab were reported in five (1%) participants in ARCADIA 2. No deaths occurred.

INTERPRETATION

Nemolizumab plus TCS-TCI was efficacious and showed statistically and clinically significant improvements in inflammation and itch in adults and adolescents with moderate-to-severe atopic dermatitis. Nemolizumab might offer a valuable extension of current therapies if approved.

FUNDING

Galderma.

Efficacy and safety of nemolizumab and topical corticosteroids for prurigo nodularis: results from a randomized double-blind placebo-controlled phase II/III clinical study in patients aged ≥ 13 years

BACKGROUND

Prurigo nodularis (PN), a chronic inflammatory skin condition, adversely affects the quality of life of affected individuals. Current treatment options for PN in Japan are limited.

OBJECTIVES

To evaluate the optimal dose, efficacy and safety of long-term treatment with nemolizumab in patients with PN in Japan.

METHODS

In a 16-week double-blind phase II/III study, patients aged ≥ 13 years with PN were randomly assigned (1 : 1 : 1) to nemolizumab 30-mg, 60-mg or placebo groups, with concomitant topical corticosteroids, every 4 weeks. The primary efficacy endpoint was the percentage change in the weekly mean Peak Pruritus Numerical Rating Scale (PP-NRS) score (range 0-10, with higher scores indicating worse itching) from baseline to week 16. Secondary efficacy endpoints assessed the impact of treatment on pruritus, PN severity, sleep and quality of life.

RESULTS

At week 16, the least-squares mean percentage change from baseline in the PP-NRS score was -61.1% in the nemolizumab 30-mg group (n = 77), -56.0% in the 60-mg group (n = 76), and -18.6% in the placebo group (n = 76). Differences between both nemolizumab groups and placebo were significant; the difference between the 30-mg and placebo groups was -42.5% [95% confidence interval (CI) -51.9 to -33.1; P < 0.0001], and between the 60-mg and placebo groups was -37.4% (95% CI -46.7 to -28.1; P < 0.0001). Patients treated with nemolizumab also had greater improvements in the number and severity of prurigo nodules, and in sleep and quality of life compared with the placebo group. Both nemolizumab doses were well tolerated.

CONCLUSIONS

Improvements in PN were greater following nemolizumab treatment, despite continuation of topical corticosteroids in both groups.

Seladelpar treatment reduces IL-31 and pruritus in patients with primary biliary cholangitis

BACKGROUND AND AIMS

Pruritus is a debilitating symptom for many people living with primary biliary cholangitis (PBC). In studies with seladelpar, a selective peroxisome proliferator-activated receptor-delta agonist, patients with PBC experienced significant improvement in pruritus and reduction of serum bile acids. Interleukin-31 (IL-31) is a cytokine known to mediate pruritus, and blocking IL-31 signaling provides relief in pruritic skin diseases. This study examined the connection between seladelpar's antipruritic effects and IL-31 and bile acid levels in patients with PBC.

APPROACH AND RESULTS

IL-31 levels were quantified in serum samples from the ENHANCE study of patients with PBC receiving daily oral doses of placebo (n = 55), seladelpar 5 mg (n = 53) or 10 mg (n = 53) for 3 months, and for healthy volunteers (n = 55). IL-31 levels were compared with pruritus using a numerical rating scale (NRS, 0-10) and with bile acid levels. Baseline IL-31 levels closely correlated with pruritus NRS ( r = 0.54, p < 0.0001), and total ( r = 0.54, p < 0.0001) and conjugated bile acids (up to 0.64, p < 0.0001). Decreases in IL-31 were observed with seladelpar 5 mg (-30%, p = 0.0003) and 10 mg (-52%, p < 0.0001) versus placebo (+31%). Patients with clinically meaningful improvement in pruritus (NRS ≥ 2 decrease) demonstrated greater dose-dependent reductions in IL-31 compared to those without pruritus improvement (NRS < 2 decrease). Strong correlations were observed for the changes between levels of IL-31 and total bile acids ( r = 0.63, p < 0.0001) in the seladelpar 10 mg group.

CONCLUSIONS

Seladelpar decreased serum IL-31 and bile acids in patients with PBC. The reductions of IL-31 and bile acids correlated closely with each other and pruritus improvement, suggesting a mechanism to explain seladelpar's antipruritic effects.

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.

Single-Cell RNA Sequencing Reveals Dysregulated POSTN+WNT5A+ Fibroblast Subclusters in Prurigo Nodularis

Prurigo nodularis (PN) is an intensely pruritic, inflammatory skin disease with a poorly understood pathogenesis. We performed single-cell transcriptomic profiling of 28,695 lesional and nonlesional PN cells. Lesional PN has increased dysregulated fibroblasts (FBs) and myofibroblasts. FBs in lesional PN were shifted toward a cancer-associated FB-like phenotype, with POSTN+WNT5A+ cancer-associated FBs increased in PN and similarly so in squamous cell carcinoma. A multicenter cohort study revealed an increased risk of squamous cell carcinoma and cancer-associated FB-associated malignancies (breast and colorectal) in patients with PN. Systemic fibroproliferative diseases (renal sclerosis and idiopathic pulmonary fibrosis) were upregulated in patients with PN. Ligand-receptor analyses demonstrated an FB neuronal axis with FB-derived WNT5A and periostin interactions with neuronal receptors melanoma cell adhesion molecule and ITGAV. These findings identify a pathogenic and targetable POSTN+WNT5A+ FB subpopulation that may predispose cancer-associated FB-associated malignancies in patients with PN.

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.

A critical evaluation of nemolizumab for prurigo nodularis

INTRODUCTION

Prurigo nodularis (PN) is a chronic inflammatory skin condition that presents with intensely pruritic, hyperkeratotic nodules. The pathophysiology underlying PN is not entirely clear, making treatment challenging. Patients often require a multimodal approach, although many of the available therapies have low efficacy or adverse effects.

AREAS COVERED

In this review, we discuss the use of nemolizumab for the treatment of PN in adults. Nemolizumab is a biological therapy that reduces type 2 cytokines and the neuroimmune response implicated in the pathophysiology of PN. It also helps maintain skin barrier integrity, which may be damaged during the vicious itch-scratch cycle. Nemolizumab has demonstrated great efficacy in improving itch and clearing lesions in recent clinical trials with respectable tolerance.

EXPERT OPINION

Nemolizumab is a promising drug for PN that seems comparable to the recently approved dupilumab in terms of its therapeutic effect and excellent safety profile, although nemolizumab may work more rapidly on itch. JAK inhibitors are also emerging as competitors of biologics for PN, however, their safety profile in this population may differ. Trials evaluating these drugs are needed to assess which is preferable. Additional data on the durability and longevity of nemolizumab for PN treatment is highly anticipated.

Prurigo nodularis: new insights into pathogenesis and novel therapeutics

Prurigo nodularis (PN) is an inflammatory skin condition characterized by intensely pruritic nodules on the skin. Patients with PN suffer from an intractable itch-scratch cycle leading to impaired sleep, psychosocial distress and a significant disruption in quality of life. The pathogenesis of PN is associated with immune and neural dysregulation, mediated by inflammatory cytokines [such as interleukin (IL)-4, -13, -17, -22 and -31] and neuropeptides (such as substance P and calcitonin gene-related peptide). There is a role for type 2 inflammation in PN in addition to T-helper (Th)17 and Th22-mediated inflammation. The neuroimmune feedback loop in PN involves neuropeptides released from nerve fibres that cause vasodilation and further recruitment of inflammatory cells. Inflammatory cells, particularly mast cells and eosinophils, degranulate and release neurotoxins, as well as nerve growth factor, which may contribute to the neuronal hyperplasia seen in the dermis of patients with PN and neural sensitization. Recent studies have also indicated underlying genetic susceptibility to PN in addition to environmental factors, the existence of various disease endotypes centred around degrees of type 2 inflammation or underlying myelopathy or spinal disc disease, and significant race and ethnicity-based differences, with African Americans having densely fibrotic skin lesions. Dupilumab became the first US Food and Drug Administration-approved therapeutic for PN, and there are several other agents currently in development. The anti-IL-31 receptor A inhibitor nemolizumab is in late-stage development with positive phase III data reported. In addition, the oral Janus kinase (JAK) 1 inhibitors, abrocitinib and povorcitinib, are in phase II trials while a topical JAK1/2 inhibitor, ruxolitinib, is in phase III studies.

Prurigo Nodularis: Pathogenesis and the Horizon of Potential Therapeutics

Chronic pruritus that lasts for over 6 weeks can present in various forms, like papules, nodules, and plaque types, with prurigo nodularis (PN) being the most prevalent. The pathogenesis of PN involves the dysregulation of immune cell-neural circuits and is associated with peripheral neuropathies, possibly due to chronic scratching. PN is a persistent and challenging condition, involving complex interactions among the skin, immune system, and nervous system. Lesional skin in PN exhibits the infiltration of diverse immune cells like T cells, eosinophils, macrophages, and mast cells, leading to the release of inflammatory cytokines and itch-inducing substances. Activated sensory nerve fibers aggravate pruritus by releasing neurotransmitters, perpetuating a vicious cycle of itching and scratching. Traditional treatments often fail, but recent advancements in understanding the inflammatory and itch transmission mechanisms of PN have paved the way for innovative therapeutic approaches, which are explored in this review.

The relationship and clinical significance of serum cytokine expression level and skin pruritus in patients with Hodgkin lymphoma and angioimmunoblastic T-cell lymphoma

Pruritus of lymphoma is commonly associated with both Hodgkin lymphoma (HL) and angioimmunoblastic T cell lymphoma (AITL) and critically affects the life quality of patient. Recent evidence suggests that the pruritogenic cytokines seem to play a significant role in the genesis of chronic. This study aims to investigate the cytokines associated with itching in lymphoma patients and provide the basis for potential therapeutic targets. Serum samples were collected from 60 lymphoma patients, including 47 with Hodgkin lymphoma (HL) and 13 with angioimmunoblastic T-cell lymphoma (AITL), serving as the observation group (lymphoma group, LP group, n = 60). Additionally, serum samples from 8 healthy donors (HD group, n = 8) were collected for comparison. Within the lymphoma group, patients were stratified into those with pruritus (LWP group, n = 30) and those without pruritus (LWOP group, n = 30) based on the presence of skin pruritus symptoms. Elevated levels of multiple cytokines were significantly observed in the LP group in comparison to the HD group (p < 0.01). Patients in LWP group exhibited higher serum levels of IL-31 (p < 0.001), IL-1β (P = 0.039), and IL-1α (P = 0.037) compared to LWOP group. Notably, serum IL-31 levels were higher in advanced AITL patients (stage IV) than in early AITL patients (stage I-Ⅲ, P < 0.05). In subgroup analysis, patients with pruritus in the AITL group exhibited higher serum levels of MIG and CTACK compared to HL group, whereas PDGF-BB levels were significantly lower (p < 0.05). Elevated serum levels of IL-31, IL-1β, and IL-1α are linked to lymphoma-associated pruritus. Differences in serum cytokine profiles between HL and AITL subgroups are also highlighted. These findings offer valuable insights for clinical intervention in managing lymphoma-related pruritus.

Potential Aspects of the Use of Cytokines in Atopic Dermatitis

Atopic dermatitis (AD) is an abnormal inflammatory response in the skin to food, environmental IgE, or non-IgE allergens. This disease belongs to a group of inflammatory diseases that affect both children and adults. In highly developed countries, AD is diagnosed twice as often in children than in adults, which may possibly be connected to increased urbanization. The immune system's pathomechanisms of AD involve humoral mechanisms with IgE, cellular T lymphocytes, dendritic cells occurring in the dermis, Langerhans cells occurring in the epidermis, and other cells infiltrating the site of inflammation (eosinophils, macrophages, mast cells, neutrophils, and basophils). Cytokines are small proteins that affect the interaction and communication between cells. This review characterizes cytokines and potential aspects of the treatment of atopic dermatitis, as well as new strategies that are currently being developed, including targeting cytokines and their receptors.

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.

Role of IL-4 and IL-13 in Cutaneous T Cell Lymphoma

The interleukins IL-4 and IL-13 are increasingly recognized contributors to the pathogenesis of cutaneous T cell lymphomas (CTCLs), and their role in disease-associated pruritus is accepted. The prevailing Th2 profile in advanced CTCL underscores the significance of understanding IL-4/IL-13 expression dynamics from the early stages of disease, as a shift from Th1 to Th2 may explain CTCL progression. Targeted agents blocking key cytokines of type 2 immunity are established therapeutics in atopic disorders and have a promising therapeutic potential in CTCL, given their involvement in cutaneous symptoms and their contribution to the pathogenesis of disease. IL-4, IL-13, and IL-31 are implicated in pruritus, offering therapeutic targets with dupilumab, tralokinumab, lebrikizumab, and nemolizumab. This review analyzes current knowledge on the IL-4/IL-13 axis in mycosis fungoides and Sezary syndrome, the most common types of CTCL, examining existing literature on the pathogenetic implications with a focus on investigational treatments. Clinical trials and case reports are required to shed light on novel uses of medications in various diseases, and ongoing research into the role of IL-4/IL-13 axis blockers in CTCL therapy might not only improve the management of disease-related pruritus but also provide in-depth insights on the pathophysiologic mechanisms of CTCL.