Delgocitinib ointment, a topical Janus kinase inhibitor, in adult patients with moderate to severe atopic dermatitis: A phase 3, randomized, double-blind, vehicle-controlled study and an open-label, long-term extension study

JAK inhibitor selectivity: new opportunities, better drugs?

Cytokines function as communication tools of the immune system, serving critical functions in many biological responses and shaping the immune response. When cytokine production or their biological activity goes awry, the homeostatic balance of the immune response is altered, leading to the development of several pathologies such as autoimmune and inflammatory disorders. Cytokines bind to specific receptors on cells, triggering the activation of intracellular enzymes known as Janus kinases (JAKs). The JAK family comprises four members, JAK1, JAK2, JAK3 and tyrosine kinase 2, which are critical for intracellular cytokine signalling. Since the mid-2010s multiple JAK inhibitors have been approved for inflammatory and haematological indications. Currently, approved JAK inhibitors have demonstrated clinical efficacy; however, improved selectivity for specific JAKs is likely to enhance safety profiles, and different strategies have been used to accomplish enhanced JAK selectivity. In this update, we discuss the background of JAK inhibitors, current approved indications and adverse effects, along with new developments in this field. We address the issue of JAK selectivity and its relevance in terms of efficacy, and describe new modalities of JAK targeting, as well as new aspects of JAK inhibitor action.

[Modern topical drugs-new developments in galenics and pharmacology]

The importance of topically applied pharmaceuticals, especially for the treatment of dermatological diseases, is still essential. Thanks to detailed knowledge of the organisation and function of the physicochemical barrier of the skin, new galenic concepts have increasingly been developed to market maturity in recent years. Colloidal drug carrier systems in particular, but also targeted physicochemical modifications of matrices are used to optimise the cutaneous bioavailability of topically applied drugs. In addition, new molecules are increasingly becoming available for the development of these preparations or drugs known from systemic therapy are being formulated into topicals. Against this background, dermatopharmacology is also developing more and more into a highly specialised science in this area, which is producing innovative concepts for the therapy of special indications. In addition to the classic small-molecule drugs, biotechnological molecules are increasingly finding their way into application, so that a modern age of dermatopharmacology has dawned, which will open up previously unimagined possibilities for topical therapy now and in the coming years.

Recent progress in tyrosine kinase 2 inhibitors for atopic dermatitis

INTRODUCTION

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by persistent itching. Conventional treatments for AD include topical corticosteroids and calcineurin inhibitors, but there are emerging therapies targeting the JAK-TYK2 pathway that are promising for the treatment of AD.

AREAS COVERED

This review comprehensively explores the pathogenesis, triggers, clinical manifestations, and conventional treatment options for AD. In addition, we discuss novel therapeutic agents targeting alternative signaling pathways, with a focus on clinical trials evaluating tyrosine kinase 2 (TYK2) inhibitors, including systemic and topical agents. We also provide a detailed assessment of ICP-332 efficacy, safety, and potential adverse effects in moderate-to-severe AD.

EXPERT OPINION

Janus kinase inhibitors that have been recently approved have shown promise for the treatment of AD, especially for patients with severe phenotypes. Preliminary findings from randomized controlled trials suggest that TYK2 inhibitors exhibit rapid efficacy and acceptable safety in the management of AD; however, additional investigations, including long-term trials, are warranted to fully understand their efficacy and safety profile.

Topical anti-inflammatory treatments for eczema: network meta-analysis

BACKGROUND

Eczema (atopic dermatitis) is the most burdensome skin condition worldwide and cannot currently be prevented or cured. Topical anti-inflammatory treatments are used to control eczema symptoms, but there is uncertainty about the relative effectiveness and safety of different topical anti-inflammatory treatments.

OBJECTIVES

To compare and rank the efficacy and safety of topical anti-inflammatory treatments for people with eczema using a network meta-analysis.

SEARCH METHODS

We searched the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, Embase and trial registries on 29 June 2023, and checked the reference lists of included studies.

SELECTION CRITERIA

We included within-participant or between-participant randomised controlled trials (RCTs) in people of any age with eczema of any severity, but excluded trials in clinically infected eczema, seborrhoeic eczema, contact eczema, or hand eczema. We included topical anti-inflammatory treatments used for at least one week, compared with another anti-inflammatory treatment, no treatment, or vehicle/placebo. Vehicle is a 'carrier system' for an active pharmaceutical substance, which may also be used on its own as an emollient for dry skin. We excluded trials of topical antibiotics used alone, complementary therapies, emollients used alone, phototherapy, wet wraps, and systemic treatments.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Primary outcomes were patient-reported eczema symptoms, clinician-reported eczema signs and investigator global assessment. Secondary outcomes were health-related quality of life, long-term control of eczema, withdrawal from treatment/study, and local adverse effects (application-site reactions, pigmentation changes and skin thinning/atrophy were identified as important concerns through patient and public involvement). We used CINeMA to quantify our confidence in the evidence for each outcome.

MAIN RESULTS

We included 291 studies involving 45,846 participants with the full spectrum of eczema severity, mainly conducted in high-income countries in secondary care settings. Most studies included adults, with only 31 studies limited to children aged < 12 years. Studies usually included male and female participants, multiple ethnic groups but predominantly white populations. Most studies were industry-funded (68%) or did not report their funding sources/details. Treatment duration and trial participation were a median of 21 and 28 days (ranging from 7 days to 5 years), respectively. Interventions used were topical corticosteroids (TCS) (172), topical calcineurin inhibitors (TCI) (134), phosphodiesterase-4 (PDE-4) inhibitors (55), janus kinase (JAK) inhibitors (30), aryl hydrocarbon receptor activators (10), or other topical agents (21). Comparators included vehicle (170) or other anti-inflammatory treatments. The risk of bias was high in 242 of the 272 (89.0%) trials contributing to data analyses, most commonly due to concerns about selective reporting. Network meta-analysis (NMA) was only possible for short-term outcomes. Patient-reported symptoms NMA of 40 trials (6482 participants) reporting patient-reported symptoms as a binary outcome ranked tacrolimus 0.1% (OR 6.27, 95% CI 1.19 to 32.98), potent TCS (OR 5.99, 95% CI 2.83 to 12.69), and ruxolitinib 1.5% (OR 5.64, 95% CI 1.26 to 25.25) as the most effective, all with low confidence. Mild TCS, roflumilast 0.15%, and crisaborole 2% were the least effective. Class-level sensitivity analysis found potent/very potent TCS had similar effectiveness to potent TCI and was more effective than mild TCI and PDE-4 inhibitors. NMA of 29 trials (3839 participants) reporting patient-reported symptoms as a continuous outcome ranked very potent TCS (SMD -1.99, 95% CI -3.25 to -0.73; low confidence) and tacrolimus 0.03% (SMD -1.57, 95% CI -2.42 to -0.72; moderate confidence) the highest. Direct information for tacrolimus 0.03% was based on one trial of 60 participants at high risk of bias. Roflumilast 0.15%, delgocitinib 0.25% or 0.5%, and tapinarof 1% were the least effective. Class-level sensitivity analysis found potent/very potent TCS had similar effectiveness to potent TCI and JAK inhibitors and mild/moderate TCS was less effective than mild TCI. A further 50 trials (9636 participants) reported patient-reported symptoms as a continuous outcome but could not be included in NMA. Clinician-reported signs NMA of 32 trials (4121 participants) reported clinician signs as a binary outcome and ranked potent TCS (OR 8.15, 95% CI 4.99, 13.57), tacrolimus 0.1% (OR 8.06, 95% CI 3.30, 19.67), ruxolitinib 1.5% (OR 7.72, 95% CI 4.92, 12.10), and delgocitinib 0.5% (OR 7.61, 95% CI 3.72, 15.58) as most effective, all with moderate confidence. Mild TCS, roflumilast 0.15%, crisaborole 2%, and tapinarof 1% were the least effective. Class-level sensitivity analysis found potent/very potent TCS more effective than potent TCI, mild TCI, JAK inhibitors, PDE-4 inhibitors; and mild TCS and PDE-4 inhibitors had similar effectiveness. NMA of 49 trials (5261 participants) reported clinician signs as a continuous outcome and ranked tacrolimus 0.03% (SMD -2.69, 95% CI -3.36, -2.02) and very potent TCS (SMD -1.87, 95% CI -2.69, -1.05) as most effective, both with moderate confidence; roflumilast 0.15%, difamilast 0.3% and tapinarof 1% were ranked as least effective. Direct information for tacrolimus 0.03% was based on one trial in 60 participants with a high risk of bias. For some sensitivity analyses, potent TCS, tacrolimus 0.1%, ruxolitinib 1.5%, delgocitinib 0.5% and delgocitinib 0.25% became some of the most effective treatments. Class-level analysis found potent/very potent TCS had similar effectiveness to potent TCI and JAK inhibitors, and moderate/mild TCS was more effective than mild TCI. A further 100 trials (22,814 participants) reported clinician signs as a continuous outcome but could not be included in NMA. Investigator Global Assessment NMA of 140 trials (23,383 participants) reported IGA as a binary outcome and ranked ruxolitinib 1.5% (OR 9.34, 95% CI 4.8, 18.18), delgocitinib 0.5% (OR 10.08, 95% CI 2.65, 38.37), delgocitinib 0.25% (OR 6.87, 95% CI 1.79, 26.33), very potent TCS (OR 8.34, 95% CI 4.73, 14.67), potent TCS (OR 5.00, 95% CI 3.80, 6.58), and tacrolimus 0.1% (OR 5.06, 95% CI 3.59, 7.13) as most effective, all with moderate confidence. Mild TCS, crisaborole 2%, pimecrolimus 1%, roflumilast 0.15%, difamilast 0.3% and 1%, and tacrolimus 0.03% were the least effective. In a sensitivity analysis of low risk of bias information (12 trials, 1639 participants), potent TCS, delgocitinib 0.5% and delgocitinib 0.25% were most effective, and pimecrolimus 1%, roflumilast 0.15%, difamilast 1% and difamilast 0.3% least effective. Class-level sensitivity analysis found potent/very potent TCS had similar effectiveness to potent TCI and JAK inhibitors and were more effective than PDE-4 inhibitors; mild/moderate TCS were less effective than potent TCI and had similar effectiveness to mild TCI. Longer-term outcomes over 6 to 12 months showed a possible increase in effectiveness for pimecrolimus 1% versus vehicle (4 trials, 2218 participants) in a pairwise meta-analysis, and greater treatment success with mild/moderate TCS than pimecrolimus 1% (based on 1 trial of 2045 participants). Local adverse effects NMA of 83 trials (18,992 participants, 2424 events) reporting application-site reactions ranked tacrolimus 0.1% (OR 2.2, 95% CI 1.53, 3.17; moderate confidence), crisaborole 2% (OR 2.12, 95% CI 1.18, 3.81; high confidence), tacrolimus 0.03% (OR 1.51, 95%CI 1.10, 2.09; low confidence), and pimecrolimus 1% (OR 1.44, 95% CI 1.01, 2.04; low confidence) as most likely to cause site reactions. Very potent, potent, moderate, and mild TCS were least likely to cause site reactions. NMA of eight trials (1786 participants, 3 events) reporting pigmentation changes found no evidence for increased pigmentation changes with TCS and crisaborole 2%, with low confidence for mild, moderate or potent TCS and moderate confidence for crisaborole 2%. NMA of 25 trials (3691 participants, 36 events) reporting skin thinning found no evidence for increased skin thinning with short-term (median 3 weeks, range 1-16 weeks) use of mild TCS (OR 0.72, 95% CI 0.12, 4.31), moderate TCS (OR 0.91, 95% CI 0.16, 5.33), potent TCS (OR 0.96, 95% CI 0.21, 4.43) or very potent TCS (OR 0.88, 95% CI 0.31, 2.49), all with low confidence. Longer-term outcomes over 6 to 60 months showed increased skin thinning with mild to potent TCS versus TCI (3 trials, 4069 participants, 6 events with TCS).

AUTHORS' CONCLUSIONS

Potent TCS, JAK inhibitors and tacrolimus 0.1% were consistently ranked as amongst the most effective topical anti-inflammatory treatments for eczema and PDE-4 inhibitors as amongst the least effective. Mild TCS and tapinarof 1% were ranked amongst the least effective treatments in three of five efficacy networks. TCI and crisaborole 2% were ranked most likely to cause local application-site reactions and TCS least likely. We found no evidence for increased skin thinning with short-term TCS but an increase with longer-term TCS.

Characteristics of gut microbiota and serum metabolism in patients with atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a chronic inflammatory skin disease that affects 15%-30% of children and 10% of adults globally, with its incidence being influenced by genetic, environmental, and various other factors. While the immune plays a crucial role in the development, the composition of gut microbiota and serum metabolites also contribute to its pathogenesis.

SUBJECT

Study the characteristics of gut microbiota and serum metabolites in patients with atopic dermatitis METHOD: In this study, we collected stool and serum samples from 28 AD patients and 23 healthy individuals (NC) for metagenomic sequencing of gut microbiota and non-targeted metabolomic sequencing of serum.

RESULT

Our results revealed a lower diversity of gut microbiota in the AD group compared to the NC group. The predominant Phylum in AD patients were Bacteroidetes, Pseudomonas, and Verrucomicrobia, with the most dominant bacterial genus being Faecalibacterium. At the species level, Prevotella copri and Faecalibacterium prausnitzii were found to be the most abundant bacteria. Significant differences in serum metabolite profiles were observed between NC and AD patients, with noticeable variations in metabolite expression levels. The majority of metabolites in the serum of AD patients exhibited low expression, while a few showed high expression levels. Notably, metabolites such as Cholesterol glucuronide, Styrene, Lutein, Betaine, Phosphorylcholine, Taurine, and Creatinine displayed the most pronounced alterations.

CONCLUSION

These findings contribute to a further understanding of the complexities underlying this disease.

Topical Application of a PDE4 Inhibitor Ameliorates Atopic Dermatitis through Inhibition of Basophil IL-4 Production

Phosphodiesterase 4 inhibitors have been approved for the treatment of atopic dermatitis. However, the cellular and molecular mechanisms underlying their therapeutic effect remain to be fully elucidated. In this study, we addressed this unsolved issue by analyzing the action of difamilast, a novel phosphodiesterase 4 inhibitor, on an oxazolone-induced skin allergic inflammation commonly used as a mouse model of atopic dermatitis. Topical application of difamilast ameliorated skin inflammation in association with reduced IL-4 expression even when the treatment commenced 4 days after the initiation of oxazolone challenge, showing its therapeutic effect on atopic dermatitis. IL-4-deficient mice displayed milder skin inflammation than did wild-type mice, and the difamilast treatment had little or no further therapeutic effect. This was also the case in mice depleted of basophils, predominant producers of IL-4 in the skin lesion, suggesting that difamilast may act on basophils. Notably, basophils accumulating in the skin lesion showed highly upregulated expression of Pde4b encoding the B subtype of the phosphodiesterase 4 family. Difamilast suppressed IL-4 production from basophils activated in vitro, at least in part, through inhibition of ERK phosphorylation. Taken together, difamilast appeared to ameliorate atopic dermatitis inflammation through the suppression of basophil IL-4 production in the skin lesion.

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.

Topical Treatments in Atopic Dermatitis: An Expansive Review

Atopic dermatitis (AD) is a common inflammatory skin condition found worldwide. It impacts patient quality of life (QoL) and is thought to arise as an inflammatory response to epidermal barrier dysfunction and hypersensitivity. AD can lead to large out-of-pocket costs and increased healthcare expenses over a lifetime. An analysis of all randomized control trials conducted since 1990 on topical therapies for AD were reviewed, including 207 trials in the final analysis. It was found that an average of 226 patients were enrolled over 2.43 arms. Common topical treatments included corticosteroids, calcineurin inhibitors, JAK inhibitors, and phosphodiesterase inhibitors. The most utilized tools to identify treatment efficacy were the EASI, IGA, SCORAD, and PGA. There was a paucity of data on trials that evaluated efficacy, QoL, and cost of treatment simultaneously. This review highlights the need for comprehensive trials that evaluate multiple aspects of treatment, including financial cost and QoL impact, to ensure each patient has the best treatment modality for the management of their AD.

Comparative efficacy and safety of JAK inhibitors in the treatment of moderate-to-severe alopecia areata: a systematic review and network meta-analysis

We performed a Bayesian network meta-analysis to indirectly compare the relative efficacy and safety of the latest JAK inhibitors for moderate-to-severe alopecia areata (AA). 13 trials totaling 3,613 patients were included. Two low-dose groups of oral formulations (ritlecitinib 10mg and ivarmacitinib 2mg) and two topical formulations (delgocitinib ointment and ruxolitinib cream) appeared to be relatively ineffective against moderate-to-severe AA. Ranking analysis suggested that brepocitinib 30mg has the best relative effect in reducing the SALT score (sucra = 0.9831), and demonstrated comparable efficacy to deuruxolitinib 12mg (sucra = 0.9245), followed by deuruxolitinib 8mg (sucra = 0.7736). Regarding the SALT50 response, brepocitinib 30mg ranked highest (sucra = 0.9567), followed by ritlecitinib 50mg (sucra = 0.8689) and deuruxolitinib 12mg (sucra = 0.7690). For achieving the SALT75 response, deuruxolitinib 12mg had the highest probability (sucra = 0.9761), followed by deuruxolitinib 8mg (sucra = 0.8678) and brepocitinib 30mg (sucra = 0.8448). Deuruxolitinib 12mg might be the most effective therapy for patients with severe AA (sucra = 0.9395), followed by ritlecitinib 50mg (sucra = 0.8753) and deuruxolitinib 8mg (sucra = 0.8070). Deuruxolitinib 12mg/8mg demonstrated notable efficacy for moderate-to-severe AA, and is expected to be a new treatment option for AA. It was worth noting that deuruxolitinib exhibit a greater likelihood of causing adverse events in comparison to other JAK inhibitors. Ritlecitinib 50mg seemed to exhibit fewer adverse effects in the high-dose groups of oral JAK inhibitors and might be an optimal choice to balance safety and efficacy. The majority of JAK inhibitors exhibited acceptable short-term safety profiles. To enhance the applicability and accuracy of our research, further head-to-head trials with longer follow-up periods are needed. Systematic Review Registration: identifier [CRD42022368012].

Current and emerging drugs for the treatment of pruritus: an update of the literature

INTRODUCTION

Pruritus, particularly in its chronic form, often imposes significant suffering and reductions in patients' quality of life. The pathophysiology of itch is varied depending on disease context, creating opportunities for unique drug development and multimodal therapy.

AREAS COVERED

The purpose of this article is to provide an update of the literature regarding current and emerging therapeutics in itch. We review the multitudes of drug targets available and corresponding drugs that have shown efficacy in clinical trials, with a particular emphasis on phase 2 and 3 trials and beyond. Broadly, these targets include therapies directed against type 2 inflammation (i.e. Th2 cytokines, JAK/STAT, lipid mediators, T-cell mediators, and other enzymes and receptors) and neural receptors and targets (i.e. PARs, TRP channels, opioid receptors, MRGPRs, GABA receptors, and cannabinoid receptors).

EXPERT OPINION

Therapeutics for itch are emerging at a remarkable pace, and we are entering an era with more and more specialized therapies. Increasingly, these treatments are able to relieve itch beyond their effect on inflammation by directly targeting the neurosensory system.

Updates in atopic dermatitis for the primary care physician: A review of advances in the understanding and treatment of atopic dermatitis

Atopic dermatitis (AD) is a common inflammatory skin condition occurring in both pediatric and adult patients. Pruritus is a clinical hallmark of the disease, and patients with AD often experience disruptions to their quality of life. The pathogenesis of AD is a complex and multifactorial interplay between genetic factors, epidermal barrier disruption, and immune dysregulation. Clinically, AD is characterized by pruritus, eczematous skin changes, and age-specific lesion distribution patterns. Infants and young children tend to have AD lesions on their face and extensor surfaces of their extremities while older children and adults tend to have AD lesions on flexural surfaces of their extremities. Many patients also experience a chronic and relapsing disease course. Due to the chronicity and severe pruritus, lesions often undergo secondary changes like lichenification. Patients with AD can experience a number of comorbidities including other atopic disease (i.e. allergic rhinitis, asthma), skin infections, cardiovascular, and neuropsychiatric illnesses. Management of AD depends on the severity of the disease as well as the distribution of the disease. Traditionally, treatment of AD included the use of moisturizers / emollients, topical corticosteroids or topical calcineurin inhibitors, or systemic therapy with non-selective immunosuppressants such as corticosteroids, cyclosporine, azathioprine, or similar. However, in the past decade, new biologic and small molecule drugs, both topical and systemic, have become important therapeutic options for AD patients, especially for those with moderate-to-severe disease. The development of these medications, following decades of research to better understand AD, are designed to specifically target various components of immune dysregulation and inflammation implicated in the pathogenesis of AD. Their successful development and deployment now allow for an exciting new era of treatment for individuals suffering from atopic dermatitis.

Novel Topical Treatments for Itch

The experience of itch often poses a burden on patient quality of life and has the capacity to inflict significant suffering. Topical therapies are a mainstay of treatment for many cutaneous and systemic diseases and afford patients the opportunity to manage their conditions without many of the systemic side effects of non-topical therapies. We review a multitude of new topical medications targeting the skin, immune system, and neural receptors. The list includes Janus kinase inhibitors, tyrosine kinase inhibitors, phosphodiesterase inhibitors, transient receptor vanilloid inhibitors, topical cannabinoids, and topical acetaminophen. Many of the topical therapies reviewed show promising data in phase 2-3 clinical trials, but further research is needed to compare therapies head-to-head and test their efficacy on a broader range of conditions.

JAK inhibitors for the treatment of vitiligo

Vitiligo is an autoimmune disease involving melanocyte-targeting T cells initiated by environmental and genetic factors. Steroids and tacrolimus have been used as topical treatments. Recently, novel topical agents targeting Janus kinase (JAK), a family of tyrosine kinases that regulates cytokine signaling, have emerged. Ruxolitinib is the first approved in vitiligo therapy. Furthermore, ritlecitinib is currently under clinical trials for oral treatment of active vitiligo. In this review, we discuss the possibility of topical JAK inhibitors as promising options for the treatment of vitiligo with regard to their mechanism of action, efficacy and safety.

Selectivity, efficacy and safety of JAKinibs: new evidence for a still evolving story

Fundamental insight gained over the last decades led to the discovery of cytokines as pivotal drivers of inflammatory diseases such as rheumatoid arthritis, psoriasis/psoriasis arthritis, inflammatory bowel diseases, atopic dermatitis and spondylarthritis. A deeper understanding of the pro-inflammatory and anti-inflammatory effects of various cytokines has prompted new cytokine-targeting therapies, which revolutionised the treatment options in the last years for patients with inflammatory disorders. Disease-associated immune responses typically involve a complex interplay of multiple cytokines. Therefore, blockade of one single cytokine does not necessarily lead to a persistent remission in all patients with inflammatory disorders and fostered new therapeutic strategies targeting intracellular pathways shared by multiple cytokines. By inhibiting JAK-STAT signalling pathways common to families of cytokines, JAK-inhibitors (JAKinibs) have created a new paradigm for the treatment of inflammatory diseases. Multiple agents have been approved for various disorders and more are being investigated for several new indications. Second-generation selective JAKinibs have been devised with the aim to achieve an increased selectivity and a possible reduced risk of side effects. In the current review, we will summarise the current body of evidence of pan versus selective JAKinibs and the most recent insights on new side effects and indications, including COVID-19.

Cardiovascular and Venous Thromboembolic Risk With JAK Inhibitors in Immune-Mediated Inflammatory Skin Diseases: A Systematic Review and Meta-Analysis

Importance

Janus kinase (JAK) inhibitors are an effective treatment option for patients with certain skin-related conditions, such as atopic dermatitis, alopecia areata, and vitiligo, but there is a current US Food and Drug Administration (FDA) boxed warning label for oral and topical JAK inhibitors regarding increased risk of major adverse cardiovascular events (MACE), venous thromboembolism (VTE), serious infections, malignant neoplasm, and death. However, this boxed warning was precipitated by results of the Oral Rheumatoid Arthritis Trial (ORAL) Surveillance study, which only included patients with rheumatoid arthritis, and the same association may not be observed in dermatologic conditions.

Objective

To determine the risk of all-cause mortality, MACE, and VTE with JAK inhibitors in patients with dermatologic conditions.

Data Sources

PubMed and ClinicalTrials.gov were searched from database inception to April 1, 2023.

Study Selection

This review included phase 3 randomized clinical trials with a placebo/active comparator group of JAK inhibitors used for a dermatologic indication with FDA approval or pending approval or with European Union or Japanese approval. Studies without a comparison group, case reports, observational studies, and review articles were excluded.

Data Extraction and Synthesis

This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Adverse events using odds ratios (ORs) and 95% CIs were calculated using a random-effects model and the DerSimonian-Laird method. Studies were screened, data abstracted, and quality assessed by 2 independent authors. The protocol was prospectively registered with PROSPERO.

Main Outcomes and Measures

Primary outcomes were a composite of adjudicated MACE and all-cause mortality, and VTE.

Results

The analysis included 35 randomized clinical trials with 20 651 patients (mean [SD] age, 38.5 [10.1] years; male, 54%) and a mean (SD) follow-up time of 4.9 (2.68) months. Findings did not show a significant difference between JAK inhibitors and placebo/active comparator in composite MACE and all-cause mortality (OR, 0.83; 95% CI, 0.44-1.57) or VTE (OR, 0.52; 95% CI, 0.26-1.04).

Conclusions and Relevance

In this systematic review and meta-analysis, use of JAK inhibitors was not associated with increased risk of all-cause mortality, MACE, and VTE compared to the placebo/active comparator groups. Additional trials with long-term follow-up are needed to better understand the safety risks of JAK inhibitors used for dermatologic indications.

Safety, efficacy, and pharmacokinetics of delgocitinib ointment in infants with atopic dermatitis: A phase 3, open-label, and long-term study

BACKGROUND

Delgocitinib ointment, a topical Janus kinase inhibitor, is used as treatment of patients with atopic dermatitis (AD) aged ≥2 years in Japan. Although initiating appropriate and early treatment upon the onset of AD in childhood is important, the safety and efficacy of delgocitinib ointment in infants with AD have not been established.

METHODS

This phase 3 study was conducted from October 2020 to June 2022 (number JapicCTI-205412). Eligible Japanese infants with AD aged 6 to <24 months received 0.25% or 0.5% of delgocitinib ointment twice daily for 52 weeks in an open-label uncontrolled manner. Topical corticosteroids were allowed to apply for worsening AD during the treatment period at the investigators' discretion.

RESULTS

A total of 22 infants were enrolled. Adverse events (AEs) were reported in 21 (95.5%) infants and were mostly mild. No treatment-related AEs were reported. The Modified Eczema Area and Severity Index (mEASI) score continuously decreased until week 4, and the score reduction was maintained until week 52. The mean percent changes in the mEASI score from baseline were -73.5% at week 4, -81.7% at week 28, and -81.9% at week 52. Delgocitinib was not detected in the plasma of most infants (68.2%-95.2%).

CONCLUSIONS

Delgocitinib ointment is well tolerated and effective for up to 52 weeks when applied to Japanese infants with AD.

Topical treatments for atopic dermatitis (eczema): Systematic review and network meta-analysis of randomized trials

BACKGROUND

Atopic dermatitis (AD) is a common skin condition with multiple topical treatment options, but uncertain comparative effects.

OBJECTIVE

We sought to systematically synthesize the benefits and harms of AD prescription topical treatments.

METHODS

For the 2023 American Academy of Allergy, Asthma & Immunology and American College of Allergy, Asthma, and Immunology Joint Task Force on Practice Parameters AD guidelines, we searched MEDLINE, EMBASE, CENTRAL, CINAHL, LILACS, ICTRP, and GREAT databases to September 5, 2022, for randomized trials addressing AD topical treatments. Paired reviewers independently screened records, extracted data, and assessed risk of bias. Random-effects network meta-analyses addressed AD severity, itch, sleep, AD-related quality of life, flares, and harms. The Grading of Recommendations Assessment, Development and Evaluation approach informed certainty of evidence ratings. We classified topical corticosteroids (TCS) using 7 groups-group 1 being most potent. This review is registered in the Open Science Framework (https://osf.io/q5m6s).

RESULTS

The 219 included trials (43,123 patients) evaluated 68 interventions. With high-certainty evidence, pimecrolimus improved 6 of 7 outcomes-among the best for 2; high-dose tacrolimus (0.1%) improved 5-among the best for 2; low-dose tacrolimus (0.03%) improved 5-among the best for 1. With moderate- to high-certainty evidence, group 5 TCS improved 6-among the best for 3; group 4 TCS and delgocitinib improved 4-among the best for 2; ruxolitinib improved 4-among the best for 1; group 1 TCS improved 3-among the best for 2. These interventions did not increase harm. Crisaborole and difamilast were intermediately effective, but with uncertain harm. Topical antibiotics alone or in combination may be among the least effective. To maintain AD control, group 5 TCS were among the most effective, followed by tacrolimus and pimecrolimus.

CONCLUSIONS

For individuals with AD, pimecrolimus, tacrolimus, and moderate-potency TCS are among the most effective in improving and maintaining multiple AD outcomes. Topical antibiotics may be among the least effective.

Protein kinases: drug targets for immunological disorders

Protein kinases play a major role in cellular activation processes, including signal transduction by diverse immunoreceptors. Given their roles in cell growth and death and in the production of inflammatory mediators, targeting kinases has proven to be an effective treatment strategy, initially as anticancer therapies, but shortly thereafter in immune-mediated diseases. Herein, we provide an overview of the status of small molecule inhibitors specifically generated to target protein kinases relevant to immune cell function, with an emphasis on those approved for the treatment of immune-mediated diseases. The development of inhibitors of Janus kinases that target cytokine receptor signalling has been a particularly active area, with Janus kinase inhibitors being approved for the treatment of multiple autoimmune and allergic diseases as well as COVID-19. In addition, TEC family kinase inhibitors (including Bruton's tyrosine kinase inhibitors) targeting antigen receptor signalling have been approved for haematological malignancies and graft versus host disease. This experience provides multiple important lessons regarding the importance (or not) of selectivity and the limits to which genetic information informs efficacy and safety. Many new agents are being generated, along with new approaches for targeting kinases.

Transepidermal Water Loss and T-helper 2 (Th2)-Associated Inflammatory Markers in Two Pediatric Patients During the First Four Weeks of Treatment With the Oral Janus Kinase Inhibitor Upadacitinib

Few studies have evaluated the effects of upadacitinib on skin barrier function and T-helper 2 (Th2)-associated inflammatory biomarkers in severe atopic dermatitis (AD). In this study, we followed two pediatric patients with AD who had previously failed to respond to conventional treatment and measured their serum Th2-associated chemokine thymus and activation-regulated chemokine (TARC) and serine protease inhibitor squamous cell carcinoma antigen (SCCA) 2 levels and transepidermal water loss (TEWL) during the first four weeks of upadacitinib treatment. Both patients showed marked clinical improvement and decreased TEWL, blood eosinophil counts, and serum TARC and SCCA2 levels after four weeks of upadacitinib treatment. These findings suggest that upadacitinib attenuates Th2-associated inflammatory markers and promotes skin barrier integrity.

Short-term efficacy and safety of biologics and Janus kinase inhibitors for patients with atopic dermatitis: A systematic review and meta-analysis

Background

In recent years, biologics targeting key cytokines and Janus kinase (JAK) inhibitors have demonstrated favorable efficacy and safety outcomes for atopic dermatitis (AD) therapy. To evaluate the short-term efficacy and safety of AD therapy involving biologics, JAK inhibitors, and their combination with topical corticosteroids (TCS) for patients with AD, we conducted this systematic review and meta-analysis. Using eligible randomized clinical trials (RCTs) of 12 or 16 weeks of treatment with systemic medications and 4 weeks of topical treatment for AD.

Methods

PubMed, Web of Science, ScienceDirect, and the Cochrane Library were searched from inception up to October 25, 2023. English-language randomized clinical trials (RCTs) of 12 or 16 weeks of treatment with systemic medications and 4 weeks of topical treatment for AD were included. Titles, abstracts, and articles were screened in duplicate. Of 7261 citations, 37 studies were included. The data were analyzed using Review Manager 5.4 and the outcomes were measured by the Eczema Area and Severity Index (EASI), Investigator Global Assessment (IGA), the pruritus Numerical Rating Scale (NRS), as well as instances of adverse events (AE), and serious AE (SAE), which were presented as risk ratio (RR) with a 95 % confidence interval (CI). The efficacy of the biological therapies was analyzed with the percentage of patients who have achieved EASI 75, EASI 90, IGA 0/1 and pruritus NRS4, while the safety of treatments was evaluated in terms of the number of patients who had ≥1 AE and who had at least one SAE.

Results

A total of 37 studies with 43 cohorts that examined 9 medications and placebo and involved 18172 participants were included. Compared with the placebo, all biologics and JAK inhibitors were associated with a higher response rate in efficacy outcomes, while systematic administration was presented by dupilumab 200 mg subcutaneously every 2 weeks with superior improvement in EASI 90 (RR 9.50, 95 % CI 2.31-39.03) and IGA0/1 (RR 17.00, 95 % CI 2.33-123.78), upadacitinib 30 mg once daily in EASI 75 (RR 5.14, 95 % CI 4.20-6.31) and Pruritus NRS4 (RR 5.73, 95 % CI 4.44-7.39), and external use was presented by ruxolitinib 1.5 % twice daily orally in EASI 75 (RR 4.14, 95 % CI 3.06-5.61) and Pruritus NRS4 (RR 4.08, 95 % CI 2.86-5.81), and most of doses led to a better safety profile. Most doses of baricitinib, dupilumab, tralokinumab, and upadacitinib in combination with TCS demonstrated good efficacy as compared with the control groups (placebo + TCS). However, patients receiving baricitinib at a dosage of 2 mg daily (RR 1.23, 95 % CI 1.02-1.49) and 4 mg daily (RR 1.39, 95 % CI 1.22-1.58) in combination with TCS, exhibited a higher incidence of one or more SAE as compared with those taking placebo + TCS.

Conclusion

Our research has revealed that ruxolitinib and dupilumab are effective and safe treatments for mild to moderate AD and moderate to severe AD, respectively. Additionally, the combination of dupilumab and TCS demonstrates greater efficacy and safety compared to baricitinib, tralokinumab, and upadacitinib with TCS as a background treatment for moderate to severe AD. We suggest that the use of topical JAK inhibitors could be a potential alternative to TCS when used in combination with systemic medications, as a novel approach to treat AD. Insufficient different data sources caused by partial interventions were only mentioned in a few articles and low event rates in safety analyses may lead to the results being biased. Further studies directly comparing existing and novel treatments are needed and will be included in forthcoming updates of this review. Our findings could form a useful foundation for developing a new generation of treatment guidelines for AD.

Use of Janus kinase inhibitors in atopic dermatitis - an update

Atopic dermatitis is among the cutaneous inflammatory disorders whose pathophysiology is thought to be influenced by the JAK-STAT intracellular signalling system. The effectiveness of systemic and topical Janus kinase (JAK) inhibitors in the treatment of atopic dermatitis has been shown in clinical trials and case studies. At present, oral abrocitinib (Cibinqo), oral upadacitinib (Rinvoq), oral baricitinib (Olumiant) and topical ruxolitinib (Opzelura) have approval from the US-FDA for their use in the treatment of atopic dermatitis. The efficacy and safety of oral and topical Janus kinase inhibitors for the treatment of atopic dermatitis have been reviewed in this article.

Current and Emerging Therapies for Atopic Dermatitis in the Elderly

Atopic dermatitis (AD) in the elderly has recently emerged as a distinct subgroup of AD, garnering widespread concern due to its increasing global incidence rate. Epidermal barrier dysfunction, inflammatory response, and chronic pruritus interact with each other, contributing to the pathogenesis and pathophysiology of AD in the elderly. Although fundamental medications are essential for managing AD in the elderly, older adults often struggle with regular usage of moisturizing emollients, topical medications, and avoidance of environmental triggers, leading to recurrent or even exacerbated disease progression. Therefore, a systematic medication approach is necessary to control pruritus and skin lesions. Traditional systemic treatments may not adequately meet the treatment needs of moderate and severe AD in the elderly and may even pose certain safety risks. Biologics and Janus kinase (JAK) inhibitors, exhibiting excellent clinical efficacy, have made significant breakthroughs in AD treatment. Existing evidence suggests that dupilumab, a human monoclonal IgG4 antibody, has been confirmed as an effective and safe first-line systematic treatment for moderate to severe AD in the elderly, with no notable differences between adults and the elderly. However, the limited inclusion of elderly patients in related clinical studies hinders the generalizability of these findings. As older patients face a higher risk of adverse events with JAK inhibitors, JAK inhibitors are recommended when no other suitable treatment options are available. Obtaining population-specific data is crucial for making evidence-based treatment choices when managing AD in older adults with JAK inhibitors.

Emerging role of topical Janus kinase inhibitors in dermatological disorders: a review

Janus kinase (JAK) refers to a family of tyrosine kinases that are involved in the production of proinflammatory mediators in response to various extracellular signals. The JAK-signal transducer and activator of transcription (STAT) pathway is an appealing target in many inflammatory illnesses as this pathway modulates immune cell activation and T-cell-mediated inflammation in response to several cytokines. The practical considerations of prescription for topical and oral JAK inhibitors (JAKis) in atopic dermatitis, vitiligo and psoriasis have been covered in prior publications. Currently, the US Food and Drug Administration has approved the topical JAKi ruxolitinib for atopic dermatitis and nonsegmental vitiligo. None of the remaining first- or second-generation topical JAKis have been approved for topical application in any dermatological indications so far. For this review, the PubMed database was searched using 'topical' and 'JAK inhibitor' or 'Janus kinase inhibitor' or the names of individual drug molecules as the keyword in the title with no date limits. The description of topical JAKi usage in dermatology from the literature was evaluated in each abstract. The current review concentrates on emphasizing the rising use of topical JAKis in both approved and off-label dermatological applications for both old and novel conditions.

JAK-STAT pathway inhibitors in dermatology

The JAK-STAT signaling pathway mediates important cellular processes such as immune response, carcinogenesis, cell differentiation, division and death. Therefore, drugs that interfere with different JAK-STAT signaling patterns have potential indications for various medical conditions. The main dermatological targets of JAK-STAT pathway inhibitors are inflammatory or autoimmune diseases such as psoriasis, vitiligo, atopic dermatitis and alopecia areata; however, several dermatoses are under investigation to expand this list of indications. As JAK-STAT pathway inhibitors should gradually occupy a relevant space in dermatological prescriptions, this review presents the main available drugs, their immunological effects, and their pharmacological characteristics, related to clinical efficacy and safety, aiming to validate the best dermatological practice.

Janus Kinase Inhibitors in Atopic Dermatitis: New Perspectives

The JAK/STAT (Janus kinase/signal transducer and activator of transcription) pathway is an essential final step in the signaling process of most interleukins with a critical role in the pathogenesis of atopic dermatitis. By achieving broad, intermittent inhibition of the activity of multiple cytokines, JAK inhibitors help modulate T helper 2 cell-mediated inflammation, epidermal barrier dysfunction, and itch signaling. This comprehensive blockade, however, can result in a wider range of adverse effects. We review a number of JAK inhibitors that have been recently approved for use in atopic dermatitis, such as baricitinib, upadacitinib, and abrocitinib, as well as others that are currently in the pipeline or under development, such as gusacitinib, delgocitinib, ruxolitinib, brepocitinib, tofacitinib, and cerdulatinib. The use of JAK inhibitors to block the signaling of numerous cytokines with a critical role in the pathogenesis of atopic dermatitis has revolutionized the treatment of this pathogenically complex, phenotypically heterogeneous skin disease.

[Translated article] Janus Kinase Inhibitors in Atopic Dermatitis: New Perspectives

The JAK/STAT (Janus kinase/signal transducer and activator of transcription) pathway is an essential final step in the signaling process of most interleukins with a critical role in the pathogenesis of atopic dermatitis. By achieving broad, intermittent inhibition of the activity of multiple cytokines, JAK inhibitors help to modulate T helper 2 cell-mediated inflammation, epidermal barrier dysfunction, and itch signaling. This comprehensive blockade, however, can result in a wider range of adverse effects. We review a number of JAK inhibitors that have been recently approved for use in atopic dermatitis, such as baricitinib, upadacitinib, and abrocitinib, as well as others that are currently in the pipeline or under development, such as gusacitinib, delgocitinib, ruxolitinib, brepocitinib, tofacitinib, and cerdulatinib. The use of JAK inhibitors to block the signaling of numerous cytokines with a critical role in the pathogenesis of atopic dermatitis has revolutionized the treatment of this pathogenically complex, phenotypically heterogeneous skin disease.

The immunological and structural epidermal barrier dysfunction and skin microbiome in atopic dermatitis-an update

Atopic dermatitis (AD) is a common, chronic and relapsing inflammatory skin disease with various clinical presentations and combinations of symptoms. The pathophysiology of AD is complex and multifactorial. There are several factors involved in the etiopathogenesis of AD including structural and immunological epidermal barrier defect, imbalance of the skin microbiome, genetic background and environmental factors. Alterations in structural proteins, lipids, proteases, and their inhibitors, lead to the impairment of the stratum corneum which is associated with the increased skin penetration and transepidermal water loss. The elevated serum immunoglobulin E levels and blood eosinophilia have been shown in the majority of AD patients. Type 2 T-helper cell immune pathway with increased expression of interleukin (IL)-4, IL-5, and IL-13, has an important role in the etiopathogenesis of AD. Both T cells and keratinocytes contribute to epidermal barrier impairment in AD via a dynamic interaction of cytokines and chemokines. The skin microbiome is another factor of relevance in the etiopathogenesis of AD. It has been shown that during AD flares, Staphylococcus aureus (S. aureus) colonization increased, while Staphylococcus epidermidis (S. epidermidis) decreased. On the contrary, S. epidermidis and species of Streptococcus, Corynebacterium and Propionibacterium increased during the remision phases. However, it is not clear whether skin dysbiosis is one of the symptoms or one of the causes of AD. There are several therapeutic options, targeting these pathways which play a critical role in the etiopathogenesis of AD. Although topical steroids are the mainstay of the treatment of AD, new biological therapies including IL-4, IL-13, and IL-31 inhibitors, as well as Janus kinase inhibitors (JAKi), increasingly gain more importance with new advances in the therapy of AD. In this review, we summarize the role of immunological and structural epidermal barrier dysfunction, immune abnormalities, impairment of lipids, filaggrin mutation and skin microbiome in the etiopathogenesis of AD, as well as the therapeutic options for AD and their effects on these abnormalities in AD skin.

Topical Janus kinase inhibitors in atopic dermatitis: a safety network meta-analysis

BACKGROUND

Topical Janus kinase (JAK) inhibitors are being developed for the treatment of mild to moderate atopic dermatitis. However, comparative evidence on their safety profiles is still limited.

AIM

This study aimed to compare the relative safety of topic JAK inhibitors in patients with atopic dermatitis.

METHOD

Phase 2 and 3 clinical trials (RCTs) evaluating the efficacy and safety of topical JAK inhibitors in atopic dermatitis were searched on Medline, EMBASE and clinicaltrials.gov. The following outcomes were considered: any adverse event (AE), serious AEs, AEs leading to treatment discontinuation, any infection, any application site reaction.

RESULTS

Ten RCTs were included in this network meta-analysis. Tofacitinib was associated with a reduced risk of any AE when compared with ruxolitinib (OR 0.18, 95% CrI 0.03-0.92). The analyses for the remaining outcomes did not identify other statistically significant risk differences between the topical JAK inhibitors.

CONCLUSION

Although tofacitinib seems to present a reduced risk of any adverse event compared with ruxolitinib, this was the only statistically significant result found between JAK inhibitors. Therefore, such findings should be interpreted with caution considering the scarce data available and the heterogeneity between the studies, and there is no robust evidence allowing pointing out clinically important differences between the safety profiles of the existing topical JAK inhibitors. Further pharmacovigilance activities are needed to confirm the safety profile of these drugs.

Small molecule protein kinase inhibitors approved by regulatory agencies outside of the United States

Owing to genetic alterations and overexpression, the dysregulation of protein kinases plays a significant role in the pathogenesis of many autoimmune and neoplastic disorders and protein kinase antagonists have become an important drug target. Although the efficacy of imatinib in the treatment of chronic myelogenous leukemia in the United States in 2001 was the main driver of protein kinase inhibitor drug discovery, this was preceded by the approval of fasudil (a ROCK antagonist) in Japan in 1995 for the treatment of cerebral vasospasm. There are 21 small molecule protein kinase inhibitors that are approved in China, Japan, Europe, and South Korea that are not approved in the United Sates and 75 FDA-approved inhibitors in the United States. Of the 21 agents, eleven target receptor protein-tyrosine kinases, eight inhibit nonreceptor protein-tyrosine kinases, and two block protein-serine/threonine kinases. All 21 drugs are orally bioavailable or topically effective. Of the non-FDA approved drugs, sixteen are prescribed for the treatment of neoplastic diseases, three are directed toward inflammatory disorders, one is used for glaucoma, and fasudil is used in the management of vasospasm. The leading targets of kinase inhibitors approved by both international regulatory agencies and by the FDA are members of the EGFR family, the VEGFR family, and the JAK family. One-third of the 21 internationally approved drugs are not compliant with Lipinski's rule of five for orally bioavailable drugs. The rule of five relies on four parameters including molecular weight, number of hydrogen bond donors and acceptors, and the Log of the partition coefficient.

Diagnosing Atopic Dermatitis in Skin of Color

Atopic dermatitis (AD) is a pruritic inflammatory skin disease that disproportionately affects skin of color patients. African American, Asian, and Hispanic patients carry disproportionate disease burdens, with increased prevalence, disease severity, and health care utilization. AD has a unique clinical presentation in skin of color patients, often with greater extensor involvement, dyspigmentation, and papular and lichenified presentations. Erythema is also more difficult to appreciate and can result in an underappreciation of disease severity in skin of color patients. In this review, we highlight the important manifestations of AD across all skin types, including nuances in treatment.

Safety of topical medications in the management of paediatric atopic dermatitis: An updated systematic review

AIM

New topical agents have been developed for the treatment of atopic dermatitis (AD) in recent years. This systematic review is intended to synthesize the clinical trial literature and concisely report the updated safety and adverse effects of topical medications used to treat atopic dermatitis in children.

METHODS

A systematic search of Cochrane Library, Embase, PubMed and ClinicalTrials.gov from inception to March 2022 was conducted for trials of topical medications used to treat AD in patients <18 years (PROSPERO #CRD42022315355). Included records were limited to English-language publications and studies of ≥3 weeks duration. Phase 1 studies and those that lacked separate paediatric safety reporting were excluded.

RESULTS

A total of 5005 records were screened; 75 records met inclusion criteria with 15 845 paediatric patients treated with tacrolimus, 12 851 treated with pimecrolimus, 3539 with topical corticosteroid (TCS), 700 with crisaborole and 202 with delgocitinib. Safety data was well reported in tacrolimus trials with the most frequently reported adverse events being burning sensation, pruritus and cutaneous infections. Two longitudinal cohort studies were included, one for tacrolimus and one for pimecrolimus, which found no significant increased risk of malignancy with topical calcineurin inhibitor (TCI) use in children. Skin atrophy was identified as an adverse event in TCS trials, which other medications did not. Systemic adverse events for the medications were largely common childhood ailments.

CONCLUSION

Data discussed here support the use of steroid-sparing medications (tacrolimus, pimecrolimus, crisaborole, delgocitinib) as safe options with minimal adverse events for managing paediatric AD, although a larger number of TCI studies reported burning and pruritus compared to TCS studies. TCS was the only medication class associated with reports of skin atrophy in this review. The tolerability of these adverse events should be considered when treating young children. This review was limited to English-language publications and the variable safety reporting of trial investigators. Many newer medications were not included due to pooled adult and paediatric safety data that did not meet inclusion criteria.

New molecules for atopic dermatitis treatment beyond biological therapy

PURPOSE OF REVIEW

This review aims to provide a summary of current knowledge on new topical and oral non-biological therapies recently approved for Atopic Dermatitis (AD) treatment.

RECENT FINDINGS

The immense research carried out in the last decade has focused on understanding the molecular basis underlying AD and has allowed the development of new targeted drugs. Despite several biologic therapies are approved or in development, other non-biologic targeted therapies (small molecules) have emerged, such as the Janus kinase (JAK) inhibitors baricitinib, upadacitinib and abrocitinib, expanding the range of therapeutic options. Based on recent available data from head-to-head comparisons and meta-analysis studies, JAK inhibitors showed a faster onset of action and slightly higher efficacy at 16 weeks compared with biologic agents. Concerning topical treatment, presently, corticosteroids and calcineurin inhibitors are the main therapeutic options, but are not recommended for long-term management due to potential safety issues. Currently, two topical JAK inhibitors (ruxolitinib and delgocitinib) and one phosphodiesterase 4 (PDE4) inhibitor (difamilast) are approved and have shown good efficacy results and a favorable safety profile.

SUMMARY

These new drugs (systemic and topical) are needed to increase the success of AD treatment, particularly for patients who do not or no longer respond to treatment.

JAK Signaling Is Critically Important in Cytokine-Induced Viral Susceptibility of Keratinocytes

Little is known about whether type 1 (IFNγ), 2 (IL-4/IL-13), or 3 (IL-17A/IL-22) cytokines affect the susceptibility of keratinocytes (KC) to viruses. These immune pathways predominate in various skin diseases: lupus, atopic dermatitis (AD), and psoriasis, respectively. Janus kinase inhibitors (JAKi) are approved to treat both AD and psoriasis, and are in clinical development for lupus. We evaluated whether these cytokines alter viral susceptibility of KC and determined if this effect is modulated by treatment with JAKi. Viral susceptibility to vaccinia virus (VV) or herpes simplex virus-1 (HSV-1) ± JAKi was assessed in immortalized and primary human KC pretreated with cytokines. Exposure to type 2 (IL-4 + IL-13) or the type 3 (IL-22) cytokines significantly increased KC viral susceptibility. Specifically, there was a peak increase of 12.2 ± 3.1-fold (IL-4 + IL-13) or 7.7 ± 2.8-fold (IL-22) in VV infection as measured by plaque number. Conversely, IFNγ significantly reduced susceptibility to VV (63.1 ± 64.4-fold). The IL-4 + IL-13-induced viral susceptibility was reduced (44 ± 16%) by JAK1 inhibition, while the IL-22-enhanced viral susceptibility was diminished (76 ± 19%) by TYK2 inhibition. IFNγ-mediated resistance to viral infection was reversed by JAK2 inhibition (366 ± 294% increase in infection). Cytokines expressed in AD skin (IL-4, IL-13, IL-22) increase KC viral susceptibility while IFNγ is protective. JAKi that target JAK1 or TYK2 reversed cytokine-enhanced viral susceptibility, while JAK2 inhibition reduced the protective effects of IFNγ.

Evolving cognition of the JAK-STAT signaling pathway: autoimmune disorders and cancer

The Janus kinase (JAK) signal transducer and activator of transcription (JAK-STAT) pathway is an evolutionarily conserved mechanism of transmembrane signal transduction that enables cells to communicate with the exterior environment. Various cytokines, interferons, growth factors, and other specific molecules activate JAK-STAT signaling to drive a series of physiological and pathological processes, including proliferation, metabolism, immune response, inflammation, and malignancy. Dysregulated JAK-STAT signaling and related genetic mutations are strongly associated with immune activation and cancer progression. Insights into the structures and functions of the JAK-STAT pathway have led to the development and approval of diverse drugs for the clinical treatment of diseases. Currently, drugs have been developed to mainly target the JAK-STAT pathway and are commonly divided into three subtypes: cytokine or receptor antibodies, JAK inhibitors, and STAT inhibitors. And novel agents also continue to be developed and tested in preclinical and clinical studies. The effectiveness and safety of each kind of drug also warrant further scientific trials before put into being clinical applications. Here, we review the current understanding of the fundamental composition and function of the JAK-STAT signaling pathway. We also discuss advancements in the understanding of JAK-STAT-related pathogenic mechanisms; targeted JAK-STAT therapies for various diseases, especially immune disorders, and cancers; newly developed JAK inhibitors; and current challenges and directions in the field.

Biologic Versus Small Molecule Therapy for Treating Moderate to Severe Atopic Dermatitis: Clinical Considerations

The U.S. Food and Drug Administration approval of dupilumab for moderate-to-severe atopic dermatitis shifted the paradigm from use of broad, systemic immunosuppressants to a safer, targeted treatment and led to the emergence of newer interleukin (IL)-4/IL-13 directed biologics and small molecule therapies, namely Janus kinase (JAK) inhibitors (JAKi). Tralokinumab and emerging (not yet approved) lebrikizumab, which both target IL-13, are alternative biologics to dupilumab. The emerging anti-IL-31 receptor nemolizumab is likely to be used second-line to other biologics, primarily for pruritus. Three JAKi are currently in use for treating atopic dermatitis, 2 of which, abrocitinib and upadacitinib, are U.S. Food and Drug Administration-approved. This review provides an in-depth, practical discussion on use of these biologics and JAKi that are approved or have completed phase 3 clinical trials in pediatric patients and adults, comparing the groups of medications based on available efficacy and safety data.

Long-term safety and disease control with ruxolitinib cream in atopic dermatitis: Results from two phase 3 studies

BACKGROUND

Ruxolitinib cream demonstrated safety and efficacy over 8 weeks in 2 double-blind phase 3 atopic dermatitis studies (NCT03745638/NCT03745651).

OBJECTIVE

To evaluate long-term safety (LTS) and disease control with ruxolitinib cream.

METHODS

Patients initially randomized to twice-daily 0.75%/1.5% ruxolitinib cream maintained their regimen during the 44-week LTS period (as-needed treatment). Patients on vehicle were rerandomized (1:1) at week 8 to either ruxolitinib cream strength. Safety and disease control (Investigator's Global Assessment score 0/1 and affected body surface area) were assessed.

RESULTS

Over 52 weeks, adverse events were reported in 67.4%/62.6%/53.5%/57.6% of patients in 0.75%/1.5% ruxolitinib cream/vehicle to 0.75% ruxolitinib cream/vehicle to 1.5% ruxolitinib cream groups (n = 426/446/101/99). Most common adverse events were upper respiratory tract infection (10.3%/11.4%/5.9%/7.1%) and nasopharyngitis (8.9%/9.9%/7.9%/14.1%). Most adverse events were considered unrelated to treatment. Application site reactions were infrequent (3.8%/1.8%/1.0%/1.0%). Disease control was achieved throughout the LTS; 74.1% to 77.8% of patients had Investigator's Global Assessment 0/1 at week 52, and mean affected body surface area was low (1.4%-1.8%).

LIMITATIONS

LTS had no control treatment.

CONCLUSION

During 44 weeks of as-needed treatment, ruxolitinib cream demonstrated effective disease control and tolerability; low ruxolitinib plasma concentrations alongside safety findings reflecting known risk factors suggest physiologically meaningful systemic Janus kinase inhibition is highly unlikely.

Novel Therapeutic Targets for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease that significantly impacts quality of life. The pathogenesis of AD is a complex combination of skin barrier dysfunction, type II immune response, and pruritus. Progress in the understanding of the immunological mechanisms of AD has led to the recognition of multiple novel therapeutic targets. For systemic therapy, new biologic agents that target IL-13, IL-22, IL-33, the IL-23/IL-17 axis, and OX40-OX40L are being developed. Binding of type II cytokines to their receptors activates Janus kinase (JAK) and its downstream signal, namely signal transduction and activator of transcription (STAT). JAK inhibitors block the activation of the JAK-STAT pathway, thereby blocking the signaling pathways mediated by type II cytokines. In addition to oral JAK inhibitors, histamine H4 receptor antagonists are under investigation as small-molecule compounds. For topical therapy, JAK inhibitors, aryl hydrocarbon receptor modulators, and phosphodiesterase-4 inhibitors are being approved. Microbiome modulation is also being examined for the treatment of AD. This review outlines current and future directions for novel therapies of AD that are currently being investigated in clinical trials, focusing on their mechanisms of action and efficacy. This supports the accumulation of data on advanced treatments for AD in the new era of precision medicine.

Chronic pruritus: from pathophysiology to drug design

Pruritus, the most common symptom in dermatology, is an innate response capable of protecting skin against irritants. Nonetheless, when it lasts more than six weeks it is assumed to be a chronic pathology having a negative impact on people's lives. Chronic pruritus (CP) can occur in common and rare skin diseases, having a high prevalence in global population. The existing therapies are unable to counteract CP or are associated with adverse effects, so the development of effective treatments is a pressing issue. The pathophysiological mechanisms underlying CP are not yet completely dissected but, based on current knowledge, involve a wide range of receptors, namely neurokinin 1 receptor (NK1R), Janus kinase (JAK), and transient receptor potential (TRP) ion channels, especially transient receptor potential vanilloid 1 (TRPV1) and transient receptor potential ankyrin 1 (TRPA1). This review will address the relevance of these molecular targets for the treatment of CP and molecules capable of modulating these receptors that have already been studied clinically or have the potential to possibly alleviate this pathology. According to scientific and clinical literature, there is an increase in the expression of these molecular targets in the lesioned skin of patients experiencing CP when compared with non-lesioned skin, highlighting their importance for the development of potential efficacious drugs through the design of antagonists/inhibitors.

The translational revolution in atopic dermatitis: the paradigm shift from pathogenesis to treatment

Atopic dermatitis (AD) is the most common inflammatory skin disease, and it is considered a complex and heterogeneous condition. Different phenotypes of AD, defined according to the patient age at onset, race, and ethnic background; disease duration; and other disease characteristics, have been recently described, underlying the need for a personalized treatment approach. Recent advancements in understanding AD pathogenesis resulted in a real translational revolution and led to the exponential expansion of the therapeutic pipeline. The study of biomarkers in clinical studies of emerging treatments is helping clarify the role of each cytokine and immune pathway in AD and will allow addressing the unique immune fingerprints of each AD subset. Personalized medicine will be the ultimate goal of this targeted translational research. In this review, we discuss the changes in the concepts of both the pathogenesis of and treatment approach to AD, highlight the scientific rationale behind each targeted treatment and report the most recent clinical efficacy data.

Pruritogenic Mediators and New Antipruritic Drugs in Atopic Dermatitis

Atopic dermatitis (AD) is a common highly pruritic chronic inflammatory skin disorder affecting 5-20% of children worldwide, while the prevalence in adults varies from 7 to 10%. Patients with AD experience intense pruritus that could lead to sleep disturbance and impaired quality of life. Here, we analyze the pathophysiology of itchiness in AD. We extensively review the histamine-dependent and histamine-independent pruritogens. Several receptors, substance P, secreted molecules, chemokines, and cytokines are involved as mediators in chronic itch. We also, summarize the new emerging antipruritic drugs in atopic dermatitis.

A phase 2a randomized vehicle-controlled multi-center study of the safety and efficacy of delgocitinib in subjects with moderate-to-severe alopecia areata

Alopecia areata/AA is an autoimmune cause of nonscarring hair loss. The pathogenesis of AA involves many immune axes, including Th1/Th2 pathways. Delgocitinib is a pan-Janus kinase/JAK inhibitor that broadly blocks pro-inflammatory cytokines and has been effective in other inflammatory skin conditions. Recent human studies/reports have shown that use of some systemic JAK inhibitors led to hair regrowth, suggesting this medication class as a potential therapy for AA. However, topical treatment is desirable due to potential systemic side effects. To assess the efficacy and safety of topical delgocitinib in AA, we conducted a double-blind, randomized, vehicle-controlled clinical trial in 31 moderate-to-severe AA patients that were randomized 2:1 to receive delgocitinib ointment 30 mg/g (n = 20) or ointment vehicle (n = 11) for 12 weeks. The primary endpoint was change in severity of Alopecia Tool/SALT score from baseline to week 12. The secondary endpoint included safety profile by reported adverse events. Twenty-three subjects completed the trial, with eight discontinuing mostly due to voluntary withdrawal. Ten patients receiving delgocitinib ointment and three patients receiving vehicle showed SALT score improvements after 12 weeks, but the mean percent SALT improvement at week 12 compared to baseline between the two arms was not significant (p = 0.92). Our study suggests that delgocitinib ointment is not effective in moderate-to-severe AA, likely due to its inability to penetrate sufficiently deeply into the dermis of the scalp, but larger studies are necessary to assess whether a different formulation of topical JAK inhibitors may be suitable to treat mild or more localized forms of AA.

Epicutaneous Sensitization and Food Allergy: Preventive Strategies Targeting Skin Barrier Repair-Facts and Challenges

Food allergy represents a growing public health and socio-economic problem with an increasing prevalence over the last two decades. Despite its substantial impact on the quality of life, current treatment options for food allergy are limited to strict allergen avoidance and emergency management, creating an urgent need for effective preventive strategies. Advances in the understanding of the food allergy pathogenesis allow to develop more precise approaches targeting specific pathophysiological pathways. Recently, the skin has become an important target for food allergy prevention strategies, as it has been hypothesized that allergen exposure through the impaired skin barrier might induce an immune response resulting in subsequent development of food allergy. This review aims to discuss current evidence supporting this complex interplay between the skin barrier dysfunction and food allergy by highlighting the crucial role of epicutaneous sensitization in the causality pathway leading to food allergen sensitization and progression to clinical food allergy. We also summarize recently studied prophylactic and therapeutic interventions targeting the skin barrier repair as an emerging food allergy prevention strategy and discuss current evidence controversies and future challenges. Further studies are needed before these promising strategies can be routinely implemented as prevention advice for the general population.

Itch and Janus Kinase Inhibitors

Itch is a common skin symptom, with complex aetiology and pathogenesis. It is mediated by 2 pathways, the histaminergic and non-histaminergic pathways. Chronic itch is understood to be processed by the latter and is difficult to treat with traditional pruritus therapies. The Janus kinase and signal transducer and activator of transcription pathway is a signalling mechanism that regulates gene expression through various cytokines. Janus kinase inhibitors, which have been tested and used for several autoimmune diseases, have also been shown to be effective for itch through clinical trials and case reports. Janus kinase inhibitors could be a good choice for pruritus in atopic dermatitis, psoriasis, and other diseases, such as prurigo nodularis and lichen planus, with rapid itch relief compared with conventional treatments. The most common adverse effects reported include nasopharyngitis, acne, and elevated blood creatine phosphokinase levels. Janus kinase inhibitors are currently prescribed with warnings about a potential increase in malignancies and cardiovascular diseases and usage in people of older ages. This review aims to provide knowledge about itch and the Janus kinase and signal transducer and activator of transcription pathway and to analyse the current evidence for itch relief by Janus kinase inhibitors.

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.

Efficacy and safety of topical JAK inhibitors in the treatment of atopic dermatitis in paediatrics and adults: A systematic review

Atopic dermatitis (AD) is the most common skin inflammatory disease. Dysregulation of innate and adaptive immune systems plays a major role in the pathophysiology of AD. JAKi (Janus Kinase Inhibitors) reduce the production of pro-inflammatory cytokines and represent a promising novel treatment for AD. To assess and summarize the overall efficacy and safety of topial JAKi in the treatment of AD in adults and pediatrics, a broad search was performed on Ovid Medline, Ovid Embase, Cochrane Library, Web of Sciences, Scopus, CINAHL and Google Scholar until 14 June 2022. After screening, 19 studies remained for the final review. The current systematic review was conducted according to PRISMA, and the protocol was registered in PROSPERO (ID #CRD42022303321). Topical delgocitinib, tofacitinib, ruxolitinib, cerdulatinib and ifidancitinib are effective in treating AD and significantly improve EASI, IGA, pruritus-NRS score and some other indexes in adults. Moreover, topical delgocitinib was observed to have a great efficacy in the treatment of AD in paediatrics. All topical JAKi showed minimal risk of mild-to-moderate adverse effects. Available topical JAKi are effective and safe modalities in treating AD. Nevertheless, further studies with longer duration and head-to-head comparative trials are necessary to find the best option with the least adverse effects.

Advances in Current Drugs and Formulations for the Management of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disease with a complex pathophysiology. Treatment of AD remains challenging owing to the presence of a wide spectrum of clinical phenotypes and limited response to existing therapies. However, recent genetic, immunological, and pathophysiological insights into the disease mechanism resulted in the invention of novel therapeutic drug candidates. This review provides a comprehensive overview of current therapies and assesses various novel drug delivery strategies currently under clinical investigation. Further, this review majorly emphasizes on various topical treatments including emollient therapies, barrier repair agents, topical corticosteroids (TCS), phosphodiesterase 4 (PDE4) inhibitors, calcineurin inhibitors, and Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway inhibitors. It also discusses biological and systemic therapies, upcoming treatments based on ongoing clinical trials. Additionally, this review scrutinized the use of pharmaceutical inactive ingredients in the approved topical dosage forms for AD treatment.

Rapid pruritus reduction with ruxolitinib cream treatment in patients with atopic dermatitis

BACKGROUND

Ruxolitinib cream is a topical formulation of ruxolitinib, a Janus kinase (JAK) 1/JAK2 inhibitor.

OBJECTIVES

To report timing and magnitude of effect of ruxolitinib cream on itch in patients with atopic dermatitis (AD), a highly pruritic inflammatory skin disease.

METHODS

Two phase 3 trials (TRuE-AD1 [NCT03745638]/TRuE-AD2 [NCT03745651]) enrolled patients aged ≥12 years with AD for ≥2 years, Investigator's Global Assessment score of 2 or 3, and 3%-20% affected body surface area. Patients (total N = 1249; median age, 32 years) were randomised (2:2:1) to twice daily 0.75% ruxolitinib cream, 1.5% ruxolitinib cream or vehicle cream for 8 weeks of double-blinded treatment. Worst itch was measured using the numerical rating scale (NRS).

RESULTS

Significantly more patients who applied ruxolitinib cream (either strength) achieved a ≥2-point itch reduction (NRS2) within approximately 12 h versus vehicle (0.75%/1.5% ruxolitinib cream, 16.3%/13.1%; vehicle, 6.9%; both P < 0.05), with further improvements through Week 8 (58.3%/65.1% vs 29.4%; both P < 0.0001). A ≥4-point itch reduction (NRS4) was achieved by significantly more patients who applied 0.75%/1.5% ruxolitinib cream versus vehicle by Day 2 (8.9%/11.2% vs 2.1%; P < 0.005); higher rates were observed at Week 8 (41.5%/51.5% vs 15.8%; P < 0.0001). Median time for the 0.75%/1.5% ruxolitinib cream groups to achieve NRS4 from baseline was 15.0/13.0 days; this endpoint was not reached by the vehicle group.

CONCLUSIONS

Ruxolitinib cream demonstrated rapid improvement in itch in patients with mild to moderate AD that was sustained for 8 weeks. Significantly more patients applying ruxolitinib cream achieved itch NRS2 within approximately 12 h and itch NRS4 by Day 2 versus vehicle.