Efficacy of dupilumab in chronic prurigo and chronic idiopathic pruritus: A systematic review of current evidence and analysis of response predictors

An update on mechanisms of pruritus and their potential treatment in primary cutaneous T-cell lymphoma

Primary cutaneous T-cell lymphomas (CTCL), which include mycosis fungoides (MF) and Sézary syndrome (SS), are a group of lymphoproliferative disorders characterized by clonal accumulation of neoplastic T-lymphocytes in the skin. Severe pruritus, one of the most common and distressing symptoms in primary CTCL, can significantly impair emotional well-being, physical functioning, and interpersonal relationships, thus greatly reducing quality of life. Unfortunately, effectively managing pruritus remains challenging in CTCL patients as the underlying mechanisms are, as of yet, not fully understood. Previous studies investigating the mechanisms of itch in CTCL have identified several mediators and their corresponding antagonists used for treatment. However, a comprehensive overview of the mediators and receptors contributing to pruritus in primary CTCL is lacking in the current literature. Here, we summarize and review the mediators and receptors that may contribute to pruritus in primary CTCL to explore the mechanisms of CTCL pruritus and identify effective therapeutic targets using the PubMed and Web of Science databases. Studies were included if they described itch mediators and receptors in MF and SS. Overall, the available data suggest that proteases (mainly tryptase), and neuropeptides (particularly Substance P) may be of greatest interest. At the receptor level, cytokine receptors, MRGPRs, and TRP channels are most likely important. Future drug development efforts should concentrate on targeting these mediators and receptors for the treatment of CTCL pruritus.

Effectiveness of Dupilumab for Chronic Prurigo in Chinese Patients: A Real-World Case Series Study

BACKGROUND

Treatment of chronic prurigo (CPG) is challenging. As an antagonist of IL-4R, dupilumab has shown effectiveness in treating CPG in several clinical studies. Recently, the US Food and Drug Administration (FDA) approved dupilumab for the treatment of prurigo nodularis (PN).

OBJECTIVES

The purpose of this study was to examine the efficacy of dupilumab in Chinese patients with CPG, and to analyze the difference in response between subtypes of CPG.

METHODS

This retrospective study included 18 patients with CPG who were treated with dupilumab for at least 16 weeks from March 2022 to October 2022. Disease severity and patient self-assessment questionnaires were assessed at baseline and each visit, including the peak Pruritus Visual Analogue Scale (PP-VAS), Prurigo Activity and Severity Score (PAS), Investigator Global Assessment (IGA), Dermatology Life Quality Index (DLQI), Hospital Anxiety and Depression Scale (HADS) and Itchy-specific Quality of Life questionnaire (ItchyQoL).

RESULTS

After 2 weeks of dupilumab treatment, pruritus scores were significantly reduced as measured by PP-VAS scores. Prurigo Activity and Severity scores decreased significantly at Week 2, whereas IGA improved significantly at Week 8. The DLQI, HADS, and ItchyQoL scores at Week 16 also showed significant improvement from baseline. Patients in all subtypes showed improvement in pruritus and lesion severity.

CONCLUSIONS

Dupilumab was effective in improving pruritus and lesions in patients with various subtypes of CPG.

[Management of pruritus in the elderly]

BACKGROUND

Chronic pruritus (CP), a frequent (20.3%) symptom in the elderly, increases with age. It has a significant impact on the quality of life, ranking among the 50 most burdensome diseases worldwide (Global Burden of Disease Study).

OBJECTIVES

The aim is to provide an overview of the symptom CP in the elderly and to improve differentiation of underlying conditions and management of this entity.

MATERIALS AND METHODS

A literature search in PubMed was performed, using the terms 'pruritus', 'elderly' and 'gerontodermatology'.

RESULTS

The main causes of CP in the elderly are the physiologic aging process (xerosis cutis, immunosenescence, neuropathy), the increase in potentially pruritic diseases with increasing age (diabetes mellitus, chronic renal failure), and polypharmacy. Therapeutic options relate to causes, severity of pruritus, and individual patient factors (multimorbidity, impaired organ function). The recently updated S2k guideline 'Diagnosis and therapy of chronic pruritus' is helpful.

CONCLUSION

CP in the elderly is challenging for both patients and physicians. Not only the difficulty of identifying the underlying cause, but the complexity of treatment and its tolerability and practicability determines these patients' further burden.

Single-cell RNA sequencing defines disease-specific differences between chronic nodular prurigo and atopic dermatitis

BACKGROUND

Chronic nodular prurigo (CNPG) is an inflammatory skin disease that is maintained by a chronic itch-scratch cycle likely rooted in neuroimmunological dysregulation. This condition may be associated with atopy in some patients, and there are now promising therapeutic results from blocking type 2 cytokines such as IL-4, IL-13, and IL-31.

OBJECTIVES

This study aimed to improve the understanding of pathomechanisms underlying CNPG as well as molecular relationships between CNPG and atopic dermatitis (AD).

METHODS

We profiled skin lesions from patients with CNPG in comparison with AD and healthy control individuals using single-cell RNA sequencing combined with T-cell receptor sequencing.

RESULTS

We found type 2 immune skewing in both CNPG and AD, as evidenced by CD4+ helper T cells expressing IL13. However, only AD harbored an additional, oligoclonally expanded CD8A+IL9R+IL13+ cytotoxic T-cell population, and immune activation pathways were highly upregulated in AD, but less so in CNPG. Conversely, CNPG showed signatures of extracellular matrix organization, collagen synthesis, and fibrosis, including a unique population of CXCL14-IL24+ secretory papillary fibroblasts. Besides known itch mediators such as IL31 and oncostatin M, we also detected increased levels of neuromedin B in fibroblasts of CNPG lesions compared with AD and HC, with neuromedin B receptors detectable on some nerve endings.

CONCLUSIONS

These data show that CNPG does not harbor the strong disease-specific immune activation pathways that are typically found in AD but is rather characterized by upregulated stromal remodeling mechanisms that might have a direct impact on itch fibers.

Clinical aspects and management of chronic itch

Chronic pruritus (CP) (ie, itch that persists for more than 6 weeks) poses significant challenges to patients' health and quality of life. It is a common reason for visits to dermatologists and general practitioners and can be caused by a range of conditions, including systemic diseases such as chronic kidney disease or liver diseases, malignancies, neuropathic conditions, and dermatoses such as atopic dermatitis. CP often does not develop in parallel with the course of the disease and can become an entity of its own, which must be treated with antipruritic drugs, even if the underlying cause is already under therapy. Depending on the etiology of CP, different pathways in the pathogenesis have been analyzed recently, following which new treatments have been developed and tested in randomized controlled trials. This article discusses the recent results of these studies and highlights how best to manage health care for patients with CP.

Dupilumab for Chronic Prurigo: Case Series on Effectiveness, Safety, and Quality of Life

BACKGROUND

Chronic prurigo (CPG) is a pruritic skin disease, characterized by an itch-scratch cycle and scarring. It reduces patients' quality of life (QoL). Dupilumab is a monoclonal human IgG antibody that inhibits signaling of the interleukin 4 (IL-4) and interleukin 13 (IL-13) pathways through blockade of the IL-4 receptor. Patients with CPG who receive dupilumab often report great improvement in itch and overall QoL. We therefore reviewed our experience in order to follow up on QoL, safety, and treatment response in patients with CPG who received dupilumab.

METHODS

We conducted a real-world retrospective single-center case series. Outcomes were assessed by phone interviews and photographs using validated questionnaires and scores. Demographic data were obtained from the hospital files. Follow-up was up to 2 years. We assessed QoL with the Dermatology Life Quality Index (DLQI) and the Itchy quality of life questionnaire (ItchyQoL). Numerical Rating Scale (NRS) was used to assess itch. Prurigo lesions were documented with the Prurigo activity and severity score (PAS).

RESULTS

Ten patients were included in this study. Results were reported up to 2 years after treatment with dupilumab. The response variables for DLQI, ItchyQoL, NRS, and PAS analyses showed a statistically significant decrease over time (DLQI: p ≤ 0.0001 [-0.84; -1.27], ItchyQoL: p ≤ 0.0001 [-9.89; -18.69], NRS maximum and average: p ≤ 0.0001 [-0.52; -0.86] and p ≤ 0.0001 [-0.55; -0.94], and PAS number of lesions: p = 0.0005 [-1.70; -5.28]). The percent decrease after 1 year of treatment (this estimate is based on model estimates) ranges from -42% to -82%. Four (40%) patients reported mild side effects. No serious side effects were reported.

CONCLUSION

Dupilumab treatment of CGP for up to 2 years is associated with improved QoL and less itching.

Evaluation, management and future perspectives of anal pruritus: a narrative review

PURPOSE

The without a time limitation. Most recent search was performed on 1st June 2022.

RESULTS

Thorough history and physical examination are very important in view of multiple possible causes of anal pruritus. Most of the focus during examination is drawn on to the perianal region. A digital rectal examination and an anoscopy are essential. It is necessary aim of this narrative review is to overview the classification, diagnostics, possible treatment options and future perspective of anal pruritus.

METHODS

The search was performed by two authors (AD and MJ) independently in the following electronic databases: PubMed, EMBASE, Web of Science, Cochrane Library, CENTRAL and the Allied and Complementary Medicine Databases (AMED). Search was restricted to English language only to avoid moisture and the use of soaps in the perianal region. Furthermore, the patient should avoid certain foods and increase the intake of fiber. If the symptoms do not resolve, topical steroids, capsaicin (0.006%) and tacrolimus (0.1%) ointments may be used. For intractable cases, intradermal methylene blue injection might give a long-lasting symptom relief.

CONCLUSION

Anal pruritus is a long-term deteriorating quality of life issue. Most of the time it is a symptom with a difficult diagnosis. Thorough history and examination should be performed for the best possible treatment.