Targeting key proximal drivers of type 2 inflammation in disease

Biologics and Small Molecule Inhibitors: an Update in Therapies for Allergic and Immunologic Skin Diseases

PURPOSE OF REVIEW

Biologics and small molecule inhibitors (SMIs) are a rapidly growing class of highly efficacious therapies in the treatment of chronic immunologic and allergic conditions. With precision targeting of inflammatory signaling molecules, these new agents selectively modulate the immune system to treat a variety of conditions. Dermatologic diseases, including atopic dermatitis and psoriasis, are of particular interest due to the growing number of new biologics and SMIs in recent years. This review serves to summarize and evaluate the recent literature regarding biologics and SMIs.

RECENT FINDINGS

Currently approved biologics for AD achieve clear or almost clear skin in less than 40% of patients treated. Several biologics that are still under investigation for AD have shown better efficacy in phase III trials with similar safety profiles. Recently approved SMIs for AD also demonstrate a high degree of efficacy, but safety profiles may limit their use. Psoriasis has several highly efficacious biologics on the market; however, only one SMI is currently available. Additional SMIs for psoriasis have completed phase III trials and demonstrated high efficacy. This article evaluates recent literature on biologics and small molecule inhibitors for AD and psoriasis.

Engineering human skin model innervated with itch sensory neuron-like cells differentiated from induced pluripotent stem cells

Atopic dermatitis (AD), driven by interleukins (IL-4/IL-13), is a chronic inflammatory skin disease characterized by intensive pruritus. However, it is unclear how immune signaling and sensory response pathways cross talk with each other. We differentiated itch sensory neuron-like cells (ISNLCs) from iPSC lines. These ISNLCs displayed neural markers and action potentials and responded specifically to itch-specific stimuli. These ISNLCs expressed receptors specific for IL-4/IL-13 and were activated directly by the two cytokines. We successfully innervated these ISNLCs into full thickness human skin constructs. These innervated skin grafts can be used in clinical applications such as wound healing. Moreover, the availability of such innervated skin models will be valuable to develop drugs to treat skin diseases such as AD.

Investigation of Janus Kinase (JAK) Inhibitors for Lung Delivery and the Importance of Aldehyde Oxidase Metabolism

The Janus family of tyrosine kinases (JAK1, JAK2, JAK3, and TYK2) play an essential role in the receptor signaling of cytokines that have been implicated in the pathogenesis of severe asthma, and there is emerging interest in the development of small-molecule-inhaled JAK inhibitors as treatments. Here, we describe the optimization of a quinazoline series of JAK inhibitors and the results of mouse lung pharmacokinetic (PK) studies where only low concentrations of parent compound were observed. Subsequent investigations revealed that the low exposure was due to metabolism by aldehyde oxidase (AO), so we sought to identify quinazolines that were not metabolized by AO. We found that specific substituents at the quinazoline 2-position prevented AO metabolism and this was rationalized through computational docking studies in the AO binding site, but they compromised kinome selectivity. Results presented here highlight that AO metabolism is a potential issue in the lung.

Impact of COVID-19 on patients with atopic dermatitis

Data on the tolerability and response to biologic therapies for type 2 immune disorders in the context of coronavirus disease 2019 (COVID-19) are currently lacking. Our survey aimed at assessing the adherence of patients to dupilumab therapy and the risk of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. A total of 80 patients with atopic dermatitis treated with dupilumab completed a web-based survey. Of the 80 patients, 7 discontinued dupilumab owing to concerns and difficulties related to COVID-19. Our sample was highly susceptible to viral infection owing to the frequency of risk factors including living in high SARS-CoV-2 burden areas, such as in Northern Italy; having comorbidities, such as asthma, diabetes, and cardiovascular disease; and being of advanced age. Older patients in our sample are particularly exposed to the risk of COVID-19-related cytokine storm, triggered by excessive interleukin-4 production and type 2 immune response. One patient contracted SARS-CoV-2 infection without the progression of COVID-19 despite continuing scheduled dupilumab treatment. Because evidence on the appropriate management of biologic therapy in the setting of COVID-19 is lacking, the collection of clinical data from patients in treatment with dupilumab is a valuable addition to current clinical practice. Our survey provides a contribution to the understanding of the tolerability and response to dupilumab during COVID-19 and suggests a feasible and effective approach to patients being treated with biologics even when social distancing is required.

Treatment Outcomes Associated With Dupilumab Use in Patients With Atopic Dermatitis: 1-Year Results From the RELIEVE-AD Study

Importance

Clinical trial populations may not reflect clinical practice: knowledge generated in other settings can inform clinical decision-making.

Objective

To evaluate self-reported disease control and quality of life after initiating dupilumab treatment in patients with atopic dermatitis (AD) in the the clinical setting.

Design, Setting, and Participants

This cohort study using an online survey administered prior to (baseline) and at 1, 2, 3, 6, 9, and 12 months after dupilumab initiation included adults with moderate-to-severe AD who initiated treatment with dupilumab through the US patient support program and agreed to participate in the study. Data were collected between January 2018 and January 2020 and the analysis was completed in May 2020.

Interventions

Clinically driven treatment with dupilumab.

Main Outcomes and Measures

Disease control measured by the Atopic Dermatitis Control Tool (ADCT); concomitant AD therapies; satisfaction with therapy; skin symptoms (skin pain/soreness, hot/burning feeling, sensitivity to touch) assessed using numerical rating scales; flares; health-related quality of life assessed using the Dermatology Life Quality Index; sleep problems assessed using the ADCT item and a stand-alone question; and the AD-specific Work Productivity and Activity Impairment Questionnaire.

Results

Of 699 patients who initiated dupilumab (431 [61.7%] female, 515 [73.7%] White), 632 and 483 completed the survey at months 1 and 12, respectively. As-observed results showed that most patients achieved adequate disease control (ADCT total score) at month 1 with further improvement at month 12 (385 of 632 patients [60.9%] and 374 of 483 [77.4%] for the 2 time points, respectively, vs 41 of 699 [5.3%] at baseline; both P < .001). Use of other AD therapies was reduced at each follow-up vs baseline, including topical and systemic corticosteroids, which were reduced at month 12 to 40.4% (195 of 483 patients) and 6.2% (30 of 483 patients), respectively, from 68.1% (476 of 699) and 34.9% (244 of 699), respectively, at baseline (both P < .001 vs baseline). Patient satisfaction with AD treatment was higher than baseline (120 of 699 [17.7%]) at each follow-up to 85.1% (411 of 483) at month 12 (P < .001). At each follow-up, patients reported reductions in flares, itch, skin symptoms, and improved sleep, health-related quality of life, and daily activities vs baseline. Results were consistent based on observed data and imputed data using pattern mixture models for missing data.

Conclusions and Relevance

Consistent with patient-reported outcomes in clinical trials, this cohort study found that dupilumab treatment was associated with rapid and sustained disease control for up to 12 months as demonstrated by statistically significant improvements relative to baseline on all patient-reported outcomes including treatment satisfaction.

Safety and Danger Considerations of Novel Treatments for Atopic Dermatitis in Context of Primary Cutaneous Lymphomas

The impact of new and emerging therapies on the microenvironment of primary cutaneous lymphomas (PCLs) has been recently raised in the literature. Concomitantly, novel treatments are already used or registered (dupilumab, upadacitinib) and others seem to be added to the armamentarium against atopic dermatitis. Our aim was to review the literature on interleukins 4, 13, 22, and 31, and JAK/STAT pathways in PCLs to elucidate the safety of using biologics (dupilumab, tralokinumab, fezakinumab, nemolizumab) and small molecule inhibitors (upadacitinib, baricitinib, abrocitinib, ruxolitinib, tofacitinib) in the treatment of atopic dermatitis. We summarized the current state of knowledge on this topic based on the search of the PubMed database and related references published before 21 October 2021. Our analysis suggests that some of the mentioned agents (dupilumab, ruxolitinib) and others may have a direct impact on the progression of cutaneous lymphomas. This issue requires further study and meticulous monitoring of patients receiving these drugs to ensure their safety, especially in light of the FDA warning on tofacitinib. In conclusion, in the case of the rapid progression of atopic dermatitis/eczema, especially in patients older than 40 years old, there is a necessity to perform a biopsy followed by a very careful pathological examination.

Barrier Impairment and Type 2 Inflammation in Allergic Diseases: The Pediatric Perspective

Allergic diseases represent a global burden. Although the patho-physiological mechanisms are still poorly understood, epithelial barrier dysfunction and Th2 inflammatory response play a pivotal role. Barrier dysfunction, characterized by a loss of differentiation, reduced junctional integrity, and altered innate defence, underpins the pathogenesis of allergic diseases. Epithelial barrier impairment may be a potential therapeutic target for new treatment strategies Up now, monoclonal antibodies and new molecules targeting specific pathways of the immune response have been developed, and others are under investigation, both for adult and paediatric populations, which are affected by atopic dermatitis (AD), asthma, allergic rhinitis (AR), chronic rhinosinusitis with nasal polyps (CRSwNP), or eosinophilic esophagitis (EoE). In children affected by severe asthma biologics targeting IgE, IL-5 and against IL-4 and IL-13 receptors are already available, and they have also been applied in CRSwNP. In severe AD Dupilumab, a biologic which inhibits both IL-4 and IL-13, the most important cytokines involved in inflammation response, has been approved for treatment of patients over 12 years. While a biological approach has already shown great efficacy on the treatment of severe atopic conditions, early intervention to restore epithelial barrier integrity, and function may prevent the inflammatory response and the development of the atopic march.

Baicalin ameliorates 2,4-dinitrochlorobenzene-induced atopic dermatitis-like skin lesions in mice through modulating skin barrier function, gut microbiota and JAK/STAT pathway

Baicalin has distinct therapeutic effects in various skin diseases animal models such as atopic dermatitis (AD) and psoriasis. In this study, we aimed to investigate the anti-atopic dermatitis (AD) effects of baicalin in 2,4-dinitrochlorobenzene (DNCB)-treated mice. Female BALB/c mice treated with DNCB to induce AD-like skin lesions and orally administrated with baicalin daily for 14 consecutive days. Baicalin significantly inhibited dorsal skin thickness and trans-epidermal water loss and epidermal thickness in dorsal skin. In addition, baicalin also significantly up-regulated the protein expressions of filaggrin, involucrin, and loricrin, but inhibited the inflammatory response and the activation of NF-κB and JAK/STAT pathways in the dorsal skin of the DNCB-treated mice. Furthermore, baicalin significantly restored the abundance of probiotics in the gut microbiota of the DNCB-treated mice. Pseudo germ-free (GF) DNCB-treated mice receiving fecal microbiota from baicalin donors reduced the dorsal skin thickness and skin EASI score, and inhibited the release of IgE, histamine, TNF-α and IL-4 in serum of mice. In summary, baicalin ameliorates AD-like skin lesions induced by DNCB in mice via regulation of the Th1/Th2 balance, improvement of skin barrier function and modulation of gut dysbiosis, and inhibition of inflammation through suppressing the activation of NF-κB and JAK/STAT pathways.

Prevention of Atopic Dermatitis in Mice by Lactobacillus Reuteri Fn041 Through Induction of Regulatory T Cells and Modulation of the Gut Microbiota

SCOPE

The development of atopic dermatitis (AD) in infants is closely related to the lagging development of intestinal microbiota, including that inoculated by breast milk bacteria, and immune development. Lactobacillus reuteri Fn041 is a secretory immunoglobulin A (sIgA) -coated bacterium derived from human milk.

METHODS AND RESULTS

We intervened with L. reuteri Fn041 in maternal and offspring BALB/C mice during late gestation and lactation and after weaning of the pups, respectively. AD was then induced with MC903. L. reuteri Fn041 significantly suppressed AD symptoms such as skin swelling, mast cell and eosinophil infiltration. This effect was attributed to the regulation of the systemic Th1 and Th2 cytokine ratios and the promotion of CD4⁺ CD25⁺ Foxp3⁺ regulatory T cell proliferation in mesenteric lymph nodes. It is also associated with the regulation of intestinal microbiota, particularly promoting Lactobacillus and Akkermansia.

CONCLUSIONS

Our study strengthens the understanding that breast milk-derived sIgA coated potential probiotics are involved in the development of infant intestinal microbiota, thus promoting immune development and preventing allergic diseases, and expanding the knowledge of breast milk sIgA and bacterial interactions on infant immune development. This article is protected by copyright. All rights reserved.

Pharmacokinetics and Concentration-Response of Dupilumab in Patients with Seasonal Allergic Rhinitis

Patients with moderate to severe allergic rhinitis may benefit from subcutaneous immunotherapy (SCIT), despite the risk of systemic allergic reaction. Dupilumab is a fully human monoclonal antibody that blocks the shared receptor component for interleukin (IL)-4 and IL-13, key drivers of the type 2 inflammation seen in allergic rhinitis, thereby inhibiting their signaling. In the LIBERTY Grass AID trial (NCT03558997), 16 weeks of treatment with 300 mg dupilumab every 2 weeks plus Timothy grass (TG) SCIT did not reduce TG allergen challenge nasal symptom scores compared with SCIT only but did improve tolerability of SCIT up-titration in patients with a history of grass pollen-induced seasonal allergic rhinitis. Here we present the pharmacokinetics of functional serum dupilumab and concentration-response relationships in 52 patients enrolled in this trial. Functional dupilumab concentrations and concentrations of TG-specific immunoglobulin E (IgE) and IgG4 were assessed in blood samples collected from dupilumab-only and SCIT+dupilumab-treated groups. Mean functional dupilumab concentrations were similar in both groups and reached a steady state of approximately 70-80 mg/L at week 5. One week after the end of treatment, TG-specific IgG4 concentrations were increased in the SCIT+dupilumab group, but not in the dupilumab-only group, over the range of dupilumab concentrations evaluated, whereas no changes were seen for TG-specific IgE concentrations. This study demonstrates that SCIT does not alter functional concentrations of serum dupilumab, and the impact of SCIT on TG-specific immunoglobulins is not affected by functional dupilumab concentrations over the range studied, indicating that maximum response was achieved in all patients. This article is protected by copyright. All rights reserved.

Efficacy of Dupilumab in Atopic Dermatitis: The Patient's Perspective

Introduction

Atopic dermatitis (AD), a predominantly type 2 inflammatory skin disease, affects approximately 2–5% of adults, with a high burden of disease. In moderate-to-severe AD, lesions can be extensive and pruritus intense with patients experiencing skin pain, sleep and mental health disturbances, and diminished quality of life (QoL).

Methods

The objective of this study was to evaluate the efficacy of dupilumab for the treatment of AD from the patients’ perspective using patient-reported outcome data from four clinical trials (CHRONOS, SOLO 1&2, and CAFÉ) in patients (N = 1553) receiving either the approved 300 mg q2w dupilumab with/without topical corticosteroids (TCS) dose or control (placebo or placebo + TCS). Patient Global Assessment of Disease Status (PGADS) was used to measure patients’ well-being and Patient Global Assessment of Treatment Effect (PGATE) was used to measure treatment efficacy. Patients were asked “Considering all the ways in which your eczema affects you, indicate how well you are doing” to assess their perception of well-being and “How would you rate the way your eczema responded to the study medication?” to assess their perception of treatment effect. Possible responses for both metrics included poor, fair, good, very good, and excellent.

Results

In all four studies, a significantly higher proportion of dupilumab-treated patients reported “Good”/”Very Good”/”Excellent” disease status from week 2 through study end versus control (CHRONOS, 52 weeks: 69.8% vs. 25.1%; SOLO 1&2, 16 weeks: 59.5% vs. 24.6%; CAFÉ, 16 weeks: 84.1% vs. 45.4%; all P < 0.0001), and significantly more dupilumab-treated patients reported “Good”/”Very Good”/”Excellent” treatment efficacy versus control (CHRONOS: 72.6% vs. 24.8%; SOLO 1&2: 65.0% vs. 21.1%; CAFÉ, 16 weeks: 85.0% vs. 36.1%; all P < 0.0001).

Conclusion

Adult patients with AD perceived that dupilumab with/without concomitant TCS was highly efficacious and improved overall disease status and well-being as early as week 2 and throughout treatment periods up to 1 year.

The Pathology of Type 2 Inflammation-Associated Itch in Atopic Dermatitis

Accumulated evidence on type 2 inflammation-associated itch in atopic dermatitis has recently been reported. Crosstalk between the immune and nervous systems (neuroimmune interactions) is prominent in atopic dermatitis research, particularly regarding itch and inflammation. A comprehensive understanding of bidirectional neuroimmune interactions will provide insights into the pathogenesis of itch and its treatment. There is currently no agreed cure for itch in atopic dermatitis; however, increasing numbers of novel and targeted biologic agents have potential for its management and are in the advanced stages of clinical trials. In this review, we summarize and discuss advances in our understanding of type 2 inflammation-associated itch and implications for its management and treatment in patients with atopic dermatitis.

Follistatin-Like 1 Induces the Activation of Type 2 Innate Lymphoid Cells to Promote Airway Inflammation in Asthma

Asthma is a chronic disease closely related to airway inflammation. It has been proven that type 2 innate lymphoid cells (ILC2s) play an essential role in airway inflammation in asthma. Furthermore, there is growing evidence that Follistatin-like 1 (FSTL1) can participate in various inflammatory reactions mediated by the JAK/STAT signaling pathway, among others. Therefore, we put forward a new hypothesis: FSTL1 promotes asthmatic airway inflammation by activating ILC2. This study generated an ovalbumin-sensitized asthma model in C57BL/6 and Fstl1^+/- mice. The results showed that the absolute number and the proportion of ILC2 in the ovalbumin-challenged Fstl1^+/- group were lower than in the ovalbumin-challenged wild-type group. We also measured the levels of Th2-type cytokines in the serum and bronchoalveolar lavage fluid (BALF) of mice and found that the corresponding cytokines in the Fstl1^+/- were lower than in the wild-type groups. Finally, we tested whether MEK-JAK-STAT-GATA3 is the specific pathway for FSTL1 to activate ILC2, and further tested our working hypothesis by adding various inhibitors of proteins from this pathway. Overall, these findings reveal that FSTL1 can activate ILC2 through MEK-JAK-STAT-GATA3 to promote airway inflammation and participate in the pathogenesis of asthma.

Dupilumab Provides Rapid and Sustained Clinically Meaningful Responses in Adults with Moderate-to-severe Atopic Dermatitis

Optimal management of atopic dermatitis requires a comprehensive assessment of response to treatment in order to inform therapeutic decisions. In a realworld setting, successful response to atopic dermatitis treatment is measured by sustained improvements in signs, symptoms, and quality of life. Post-hoc analyses of a 1-year, randomized, double-blinded, placebo-controlled trial (NCT02260986) of dupilumab with concomitant topical corticosteroids in 421 adults with moderate-to-severe atopic dermatitis (of whom 315/106 received placebo/dupilumab (of whom 315 received placebo and 106 received dupilumab) was performed to assess the proportion of responders to dupilumab through a multidimensional composite endpoint. At 6-months, 80.2% of dupilumab-treated vs 40.0% placebo patients (p < 0.0001) achieved improvement in signs (Eczema Area and Severity Index ≤ 7), symptoms (worst itch score ≤ 4), or quality of life (Dermatology Life Quality Index ≤5), representative of minimal/clear atopic dermatitis. All 3 endpoints, indicative of no/minimal atopic dermatitis, were achieved by 44.3% of dupilumab-treated vs 10.2% placebo patients (p < 0.0001) and sustained through 1 year. Dupilumab treatment provided sustained clinically meaningful improvement in signs, symptoms, and quality of life in adults with moderate-to-severe atopic dermatitis.

IL-4 and IL-13 Promote Proliferation of Mammary Epithelial Cells through STAT6 and IRS-1

T helper (Th)2 cytokines such as interleukin (IL)-4 and IL-13 control immune function by acting on leukocytes. They also regulate multiple responses in non-hematopoietic cells. During pregnancy, IL-4 and IL-13 facilitate alveologenesis of mammary glands. This particular morphogenesis generates alveoli from existing ducts and requires substantial cell proliferation. Using 3D cultures of primary mouse mammary epithelial cells, we demonstrate that IL-4 and IL-13 promote cell proliferation, leading to enlargement of mammary acini with partially filled lumens. The mitogenic effects of IL-4 and IL-13 are mediated by STAT6 as inhibition of STAT6 suppresses cell proliferation and improves lumen formation. In addition, IL-4 and IL-13 stimulate tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1). Prolonged treatment with these cytokines leads to increased IRS-1 abundance, which, in turn, amplifies IL-4- and IL-13-stimulated IRS-1 tyrosine phosphorylation. Through signaling crosstalk between IL-4/IL-13 and insulin, a hormone routinely included in mammary cultures, IRS-1 tyrosine phosphorylation is further enhanced. Lowering IRS-1 expression reduces cell proliferation, suggesting that IRS-1 is involved in IL-4- and IL-13-stimulated cell proliferation. Thus, a Th2-dominant cytokine milieu during pregnancy confers mammary gland development by promoting cell proliferation.

Immunological Targets of Biologic Drugs in Allergic Skin Diseases in Children

Atopic dermatitis and urticaria are two invalidating skin disorders that are very common in children. Recent advances in the understanding of their specific intracellular molecular pathways have permitted the development of precise biological molecules, targeting inflammatory mediators and arresting the pathogenetic pathways of skin diseases. Many biologics with promising results have been studied, although few are currently approved in children. In this review, we aim to provide the latest evidence about the use, indications, efficacy and safety of biologic therapies to treat atopic dermatitis and chronic urticaria in children and adolescents.

Prevalence of type 2 inflammatory diseases in pediatric patients with atopic dermatitis: real-world evidence

BACKGROUND

Patients with atopic dermatitis (AD) are considered at increased risk of developing other type 2 inflammatory diseases. However, real-world evidence based on large US commercially insured pediatric populations is scarce.

OBJECTIVE

To use a large US claims database (IBM® MarketScan® 2013-2017) to assess prevalence and incidence of type 2 inflammatory diseases in pediatric AD patients.

METHODS

Pediatric AD patients were matched 1:1 to non-AD patients. Prevalence was assessed for conjunctivitis, rhinitis, urticaria, asthma, eosinophilic esophagitis and chronic rhinosinusitis/nasal polyps, 12 months post-index date (first AD diagnosis date for AD patients; a randomly selected outpatient visit for control patients). Incidence of other type 2 inflammatory diseases post-index was assessed among patients 0-2 years old.

RESULTS

244,776 AD and matched non-AD patients were selected. The prevalence and incidence of type 2 inflammatory diseases were higher among AD patients. Overall, the prevalence more than doubled for asthma, eosinophilic esophagitis, urticaria, and rhinitis, and increased with AD severity.

LIMITATIONS

AD identification based on billing diagnoses; observation period of only 12 months; limited to commercially insured patients CONCLUSION: The burden of type 2 inflammatory diseases in pediatric AD patients is substantial, highlighting the need to optimize management of AD and its numerous associated morbidities.

Design and optimisation of a small-molecule TLR2/4 antagonist for anti-tumour therapy

In anti-tumour therapy, the toll-like receptor 2/4 (TLR2/4) signalling pathway has been a double-edged sword. TLR2/4 agonists are commonly considered adjuvants for immune stimulation, whereas TLR2/4 antagonists demonstrate more feasibility for anti-tumour therapy under specific chronic inflammatory situations. In individuals with cancer retaliatory proliferation and metastasis after surgery, blocking the TLR2/4 signalling pathway may produce favourable prognosis for patients. Therefore, here, we developed a small-molecule co-inhibitor that targets the TLR2/4 signalling pathway. After high-throughput screening of a compound library containing 14 400 small molecules, followed by hit-to-lead structural optimisation, we finally obtained the compound TX-33, which has effective inhibitory properties against the TLR2/4 signalling pathways. This compound was found to significantly inhibit multiple pro-inflammatory cytokines released by RAW264.7 cells. This was followed by TX-33 demonstrating promising efficacy in subsequent anti-tumour experiments. The current results provide a novel understanding of the role of TLR2/4 in cancer and a novel strategy for anti-tumour therapy.

Strategies Targeting Type 2 Inflammation: From Monoclonal Antibodies to JAK-Inhibitors

Bronchial asthma and its frequent comorbidity chronic rhinosinusitis (CRS), are characterized by an inflammatory process at lower and upper respiratory tract, with a variability in terms of clinical presentations (phenotypes) and distinct underpin pathophysiological mechanisms (endotypes). Based on the characteristics of inflammation, bronchial asthma can be distinguished into type 2 (eosinophilic) or nontype 2 (noneosinophilic) endotypes. In type 2 asthma endotype, the pathogenic mechanism is sustained by an inflammatory process driven by Th2 cells, type 2 innate lymphoid cells (ILC2) and type 2 cytokines, which include interleukin (IL)-4, IL-5, IL-9 and IL-13. The definition of asthma and chronic rhinusinusitis phenotype/endotype is crucial, taking into account the availability of novel biologic agents, such as monoclonal antibodies targeting the classical type 2 cytokines. Recently, new therapeutic strategies have been proposed and analyzed in preliminary clinical trials. Among them Janus kinase (JAK) inhibitors, now largely used for the treatment of other chronic inflammatory diseases such as rheumatoid arthritis and inflammatory bowel diseases, is receiving great relevance. The rationale of this strategy derives from the data that JAK is a tyrosine kinase involved in the signaling of T cell receptor and of several cytokines that play a role in allergic respiratory disease, such as IL-2, IL-4 and IL-9. In this review, we discuss whether treatment with biological agents and JAK inhibitors may be equally effective in controlling type 2 inflammatory process in both asthma and CRS.

Association Between a Type 2 Inflammatory Disease Burden Score and Outcomes Among Patients with Asthma

Background

Although prevalence of co-existing type 2 inflammatory diseases (cT2) in asthma patients has been reported, limited data exist regarding their impact on asthma outcomes.

Objective

To assess the impact of cT2 burden on asthma outcomes and to evaluate patterns of clustering of cT2 in a real-world setting.

Methods

From medical records of 4.5 million enrollees in 650 primary care practices in the UK (January 2010–December 2017), patients with ≥1 diagnosis code for asthma at any time pre-index date (date of most recent asthma-related medical encounter) and ≥2 asthma-related prescriptions during the year before index date were categorized into the Global Initiative of Asthma (GINA) guideline severity steps. A cT2 burden score (range 0–9) was assigned based on the total number of co-existing conditions (allergic conjunctivitis, allergic rhinitis, anaphylaxis, eczema/atopic dermatitis, chronic rhinosinusitis, eosinophilic esophagitis, food allergy, nasal polyps, or urticaria) for which patients received a medical diagnosis. Multivariate regression models evaluated associations between cT2 burden score and asthma exacerbations and asthma control. Factor analysis was performed to assess which cT2 comorbidities were correlated and exhibited patterns of clustering.

Results

Overall, 245,893 patients with asthma were included (mean [SD] age 44.8 [22.1] years; 43.8% male). Between 55% (GINA step 1) and 60% (GINA step 5) of asthma patients had a medical diagnosis for ≥1 other type2dx. Patients with increased cT2 burden were significantly more likely to experience asthma exacerbations and less likely to achieve asthma control.

Conclusion

Asthma patients with a higher cumulative cT2 burden score were more likely to experience worse asthma outcomes than those without any cT2 (burden score of 0).

The New Era of Biologics in Atopic Dermatitis: A Review

Atopic dermatitis (AD) is a prevalent inflammatory skin disorder affecting all age and ethnic groups. The age-dependent varying appearance and extent of pruritic lesions are accompanied by distinct individual suffering, highlighting the importance of effective treatment options. Over the past years systemic drugs have considerably extended therapeutic approaches of patients with moderate to severe AD, in particular new biologics, most notably dupilumab has appeared as major breakthrough. In addition to monoclonal blockade of IL-4 and IL-13 pathway, more cytokines have been found to play a substantial role in AD pathogenesis, presenting potential targets for new therapy options.

Dupilumab Significantly Modulates Pain and Discomfort in Patients With Atopic Dermatitis: A Post Hoc Analysis of 5 Randomized Clinical Trials

Background

Pain is a frequent symptom of atopic dermatitis (AD).

Objectives

The aims of the study were to evaluate the effects of dupilumab on pain/discomfort in AD and to determine whether pain correlates with other outcomes.

Methods

This was a post hoc analysis of 5 randomized, placebo-controlled clinical trials in which adults with chronic AD received placebo or dupilumab 300 mg every 2 weeks or once weekly with and without topical corticosteroids. Proportions of patients with no pain/discomfort on this dimension of the 5-dimension EuroQoL (EQ-5D) at week 16 (all trials) and week 52 (CHRONOS) were compared between placebo and dupilumab. Correlations were evaluated between pain/discomfort and signs and symptoms of AD.

Results

Among 2632 evaluated patients, 72.9% to 83.1% reported at least moderate pain/discomfort at baseline. Higher proportions treated with dupilumab reported no pain/discomfort at week 16 relative to placebo; risk differences ranged from 22.3% (95% confidence interval = 11.5%–33.1%) to 42.2% (95% confidence interval = 26.6%–57.8%, all P ≤ 0.0001), with similar effects observed at week 52. Correlations at baseline of pain/discomfort with signs and symptoms of AD were low to moderate.

Conclusions

Pain/discomfort, present in a substantial proportion of patients with moderate-to-severe AD, was significantly reduced by dupilumab treatment. Given the low-to-moderate correlations with other AD symptoms at baseline, pain likely represents a distinct AD symptom.

Trial Registration: ClinicalTrials.gov identifiers NCT01859988, NCT02277743, NCT02277769, NCT02260986, and NCT02755649.

Interleukins 4 and 13 drive lipid abnormalities in skin cells through regulation of sex steroid hormone synthesis

Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by skin dryness, inflammation, and itch. A major hallmark of AD is an elevation of the immune cytokines IL-4 and IL-13. These cytokines lead to skin barrier disruption and lipid abnormalities in AD, yet the underlying mechanisms are unclear. Sebaceous glands are specialized sebum-producing epithelial cells that promote skin barrier function by releasing lipids and antimicrobial proteins to the skin surface. Here, we show that in AD, IL-4 and IL-13 stimulate the expression of 3β-hydroxysteroid dehydrogenase 1 (HSD3B1), a key rate-limiting enzyme in sex steroid hormone synthesis, predominantly expressed by sebaceous glands in human skin. HSD3B1 enhances androgen production in sebocytes, and IL-4 and IL-13 drive lipid abnormalities in human sebocytes and keratinocytes through HSD3B1. Consistent with our findings in cells, HSD3B1 expression is elevated in the skin of AD patients and can be restored by treatment with the IL-4Rα monoclonal antibody, Dupilumab. Androgens are also elevated in a mouse model of AD, though the mechanism in mice remains unclear. Our findings illuminate a connection between type 2 immunity and sex steroid hormone synthesis in the skin and suggest that abnormalities in sex steroid hormone synthesis may underlie the disrupted skin barrier in AD. Furthermore, targeting sex steroid hormone synthesis pathways may be a therapeutic avenue to restoring normal skin barrier function in AD patients.

Inflammation in Asthma Pathogenesis: Role of T cells, Macrophages, Epithelial Cells and Type 2 Inflammation

Asthma is a chronic disease with abnormal inflammatory and immunological responses. The disease initiated by antigens in subjects with genetic susceptibility. However, environmental factors play a role in the initiation and exacerbation of asthma attack. Asthma is T helper 2 (Th2)-cell-mediated disease. Recent studies indicated that asthma is not a single disease entity, but it is with multiple phenotypes and endotypes. The pathophysiological changes in asthma included a series of subsequent continuous vicious circle of cellular activation contributed to induction of chemokines and cytokines that potentiate inflammation. The heterogeneity of asthma influenced the treatment response. The asthma pathogenesis driven by varied set of cells such as eosinophils, basophils, neutrophils, mast cells, macrophages, epithelial cells and T cells. In this review the role of T cells, macrophage, and epithelial cells are discussed.

Anti-Inflammatory Effect of Muscle-Derived Interleukin-6 and Its Involvement in Lipid Metabolism

Interleukin (IL)-6 has been studied since its discovery for its role in health and diseases. It is one of the most important pro-inflammatory cytokines. IL-6 was reported as an exacerbating factor in coronavirus disease. In recent years, it has become clear that the function of muscle-derived IL-6 is different from what has been reported so far. Exercise is accompanied by skeletal muscle contraction, during which, several bioactive substances, collectively named myokines, are secreted from the muscles. Many reports have shown that IL-6 is the most abundant myokine. Interestingly, it was indicated that IL-6 plays opposing roles as a myokine and as a pro-inflammatory cytokine. In this review, we discuss why IL-6 has different functions, the signaling mode of hyper-IL-6 via soluble IL-6 receptor (sIL-6R), and the involvement of soluble glycoprotein 130 in the suppressive effect of hyper-IL-6. Furthermore, the involvement of a disintegrin and metalloprotease family molecules in the secretion of sIL-6R is described. One of the functions of muscle-derived IL-6 is lipid metabolism in the liver. However, the differences between the functions of IL-6 as a pro-inflammatory cytokine and the functions of muscle-derived IL-6 are unclear. Although the involvement of myokines in lipid metabolism in adipocytes was previously discussed, little is known about the direct relationship between nonalcoholic fatty liver disease and muscle-derived IL-6. This review is the first to discuss the relationship between the function of IL-6 in diseases and the function of muscle-derived IL-6, focusing on IL-6 signaling and lipid metabolism in the liver.

The Role of Dupilumab in Severe Asthma

Dupilumab is a fully humanized monoclonal antibody, capable of inhibiting intracellular signaling of both interleukin (IL)-4 and IL-13. These are two molecules that, together with other proinflammatory cytokines such as IL-5 and eotaxins, play a pivotal role in orchestrating the airway inflammatory response defined as Type 2 (T2) inflammation, driven by Th2 or Type 2 innate lymphoid cells, which is the major feature of the T2 high asthma phenotype. The dual inhibition of IL-4 and IL-13 activities is due to the blockade of type II IL-4 receptor through the binding of dupilumab with the subunit IL-4Rα. This results in the repression of STAT6 and in the suppression of subsequent de novo formation of several molecules involved in the T2 inflammatory signature. Several clinical trials tested the efficacy and safety of dupilumab in large populations of uncontrolled severe asthmatics, revealing significant improvements in lung function, asthma control, and exacerbation rate. Similar results were reported when dupilumab was employed in patients harboring pathogenetic processes related to T2 immune response, such as atopic dermatitis and chronic rhinosinusitis. In this review, we provide an overview of the recent research in the field of respiratory medicine about dupilumab mechanism of action and its effects.

Dupilumab Demonstrates Rapid and Consistent Improvement in Extent and Signs of Atopic Dermatitis Across All Anatomical Regions in Pediatric Patients 6 Years of Age and Older

INTRODUCTION

In phase III trials in adolescents and children with atopic dermatitis (AD), dupilumab significantly decreased global disease severity. However, the effects of dupilumab on the extent and signs of AD across different anatomical regions were not reported. Here we characterize the efficacy of dupilumab in improving the extent and signs of AD across four different anatomical regions in children and adolescents.

METHODS

A post hoc subset analysis was performed using data from two randomized, double-blind, placebo-controlled, international multicenter, phase III trials of dupilumab therapy in adolescents aged ≥ 12 to < 18 years with moderate-to-severe AD and children aged ≥ 6 to < 12 years with severe AD. Endpoints included mean percentage change in Eczema Area and Severity Index (EASI) signs (erythema, edema/papulation, excoriation, lichenification) and extent of AD (measured by percentage of body surface area [% BSA] involvement) from baseline to week 16 across four anatomical regions (head and neck, trunk, upper extremities, lower extremities).

RESULTS

Dupilumab improved both the extent and severity of AD signs across the four anatomical regions. Improvements were shown to be similar across the four anatomical regions for % BSA involvement and for reduction in EASI signs. Improvements in all signs were seen early, within the first 4 weeks of treatment, and were sustained through week 16, across all regions.

CONCLUSIONS

In pediatric patients 6 years of age and older, treatment with dupilumab resulted in rapid and consistent improvement in the extent and signs of AD across all anatomical regions. CLINICALTRIALS.

GOV IDENTIFIERS

LIBERTY AD ADOL (NCT03054428) and LIBERTY AD PEDS (NCT03345914). Does dupilumab provide improvement in atopic dermatitis across all anatomical regions in children and adolescents? (MP4 48,385 kb).

Immunomodulatory Properties of Polyphenol-Rich Sugarcane Extract on Human Monocytes

As inflammatory lifestyle factors become more prevalent and as the population ages, the management of inflammation will become increasingly relevant. Plant polyphenols are powerful antioxidants that are known to have beneficial effects in a number of diseases with an inflammatory or oxidative component, such as malignancy, cardiovascular disease and arthritis. Polyphenol-rich sugarcane extract (PRSE) is a novel preparation with high concentrations of polyphenolic antioxidants, with some evidence to show benefits in health, but there is limited research investigating its effects on immunomodulation. This study determined the effects of PRSE on human monocyte cells in vitro. We show that PRSE has an immunomodulatory effect in U937 human monocyte cells, altering the expression of cellular surface markers, with an increased expression of CD16 and CD11b, as well as small changes in CD40, CD80, CD80, CD206 and MHCI. It also modulates the profile of secreted cytokines, increasing IL-1β, TNFα, IL-6, IL-8, IL-4 and IL-10. These changes are consistent with the advanced differentiation of the monocyte, as well as the switch from the M1 to M2 phenotype in macrophages. We also demonstrate that this effect is likely to be independent of the NF-κB signalling pathway, suggesting that other mechanisms drive this effect. PRSE exerts an immunomodulatory effect on U937 monocytes in vitro, potentially facilitating the conversion from inflammation to healing. Future studies should identify specific mechanisms underlying the changes and evaluate their effectiveness in animal models of disease.

Baricitinib for the treatment of atopic dermatitis

Atopic dermatitis is a common, chronic and recurrent inflammatory skin disease, which often appears in childhood but can last into adulthood. It negatively impacts patients, their families and society in general. There is a therapeutic unmet need, with patients requiring new drugs that are safe and effective. The increasing knowledge of the pathophysiology of AD and the role of the Janus kinase (JAK) and signal transducer and activator of transcription (STAT) pathway in the development and maintenance of AD, has led to the development of agents blocking this intracellular signaling pathway, the JAK inhibitors. Baricitinib shows high selectivity for JAK1 and JAK2, making it appealing for the treatment of this condition. Phase II and phase III trials evaluated the efficacy and safety of baricitinib in the treatment of AD, and the results have been encouraging, showing a good efficacy and a favorable safety and tolerability profile. At the end of 2020, EMA approved baricitinib for the treatment of adult patients with moderate-to-severe atopic dermatitis who are candidates for systemic therapy, increasing the therapeutic option for this debilitating disease.

Atopic dermatitis: an expanding therapeutic pipeline for a complex disease

Atopic dermatitis (AD) is a common chronic inflammatory skin disease with a complex pathophysiology that underlies a wide spectrum of clinical phenotypes. AD remains challenging to treat owing to the limited response to available therapies. However, recent advances in understanding of disease mechanisms have led to the discovery of novel potential therapeutic targets and drug candidates. In addition to regulatory approval for the IL-4Ra inhibitor dupilumab, the anti-IL-13 inhibitor tralokinumab and the JAK1/2 inhibitor baricitinib in Europe, there are now more than 70 new compounds in development. This Review assesses the various strategies and novel agents currently being investigated for AD and highlights the potential for a precision medicine approach to enable prevention and more effective long-term control of this complex disease.

Recent advances in understanding of the complex phenotype and mechanisms underlying atopic dermatitis (AD) have revealed multiple new potential targets for pharmacological intervention. Here, Bieber reviews therapeutic strategies and assesses the expanding pipeline for the therapy of AD, highlighting the potential for a precision medicine approach to the management of this complex disorder.

Breathing freely is possible! How to help patients with bronchial asthma and polyposis rhinosinusitis?

On June 2325, under the auspices of the Year of Science and Technology in Russia, the 17th International Interdisciplinary Congress of Allergology and Rhinosinusitis was held in Moscow. The 17th International Interdisciplinary Congress of Allergology and Immunology, where the results of current research, approaches to therapy and prevention of diseases based on modern clinical guidelines were presented. The event included a symposium "Breathe freely it is possible! How to help patients with bronchial asthma and polyposis rhinosinusitis?" with the participation of leading Russian specialists.

New possibilities of therapy of T2-associated diseases

New opportunities for the treatment of T2-associated diseases in recent years, the number of patients with atopic dermatitis (ATD), having a moderate and severe form of course, has been increasing. According to research, 30% of the world's population suffer from allergic diseases, such as bronchial asthma (BA), ATD, food allergies, anaphylaxis, chronic polypous rhinosinusitis. The development of these diseases is based on the pathophysiological mechanism of T2-mediated immune inflammation, where cytokines IL-4 and IL-13 play a key role. Diseases based on this type of inflammation belong to the group of T2-associated diseases. Thanks to targeted therapy with dupilumab, which affects the main links of pathogenesis, it is possible to effectively cope with the main manifestations of severe and moderate ATD and BA. Aim. To evaluate the effectiveness of biological therapy with dupilumab 300 mg subcutaneously for 52 weeks of T2-associated diseases, including a combination of severe ATD and BA, uncontrolled course in a teenager C. (born 2006). Materials and methods. The analysis of the medical history of the patient C., born in 2006, who received therapy with dupilumab 300 mg subcutaneously every 2 weeks for 52 weeks with the diagnosis Main: ATD, common form, severe course. Secondary diagnosis: BA, persistent course, uncontrolled, moderate severity. Dynamic monitoring of the total blood count with the calculation of the absolute number of eosinophils in peripheral blood was performed. The allergological examination included the determination of specific IgE-AT to 300 allergens using ALEX2 technology. Criteria for the effectiveness of ATD therapy were evaluated on the SCORAD scale in dynamics, an AST test was used for BA, as well as a study of the function of external respiration before treatment and during therapy. Results. The study showed high efficacy and safety of biological therapy with dupilumab 300 mg subcutaneously every 2 weeks for 52 weeks of T2-associated diseases, including a combination of severe ATD and BA, uncontrolled course in patient C. (born in 2006). The conducted allergological examination with the help of the ALEX2 Allergochip made it possible to establish the molecular components of the primary causal allergens, predict the course of an allergic disease, and carry out successful elimination measures against food allergens, preserving the maximum set of nutrients in the patient's diet. Conclusion. Therapy with dupilumab 300 mg subcutaneously every 2 weeks for 52 weeks of T2-associated diseases, with manifestations of severe ATD and BA, uncontrolled course leads to clinically significant improvement in the course of diseases, control of symptoms of diseases. ATD shows a decrease in itching of the skin, normalization of sleep, improvement of quality of life. With BA, a significant reduction in exacerbations, normalization of respiratory function indicators, complete control of the disease has been achieved. The targeted biological drug dupilumab has a targeted effect on the key links in the pathogenesis of ATD and BA and reduces the burden of severe diseases. Therefore, the use of dupilumab in ATD and BA contributes to achieving disease control and improving the patient's quality of life.

Human Lung-Resident Macrophages Express and Are Targets of Thymic Stromal Lymphopoietin in the Tumor Microenvironment

Thymic stromal lymphopoietin (TSLP) is a pleiotropic cytokine highly expressed by epithelial cells and several innate and adaptive immune cells. TSLP exerts its biological effects by binding to a heterodimeric complex composed of TSLP receptor (TSLPR) and IL-7Rα. In humans, there are two TSLP isoforms: the short form (sfTSLP), constitutively expressed, and the long form (lfTSLP), which is upregulated in inflammation. TSLP has been implicated in the induction and progression of several experimental and human cancers. Primary human lung macrophages (HLMs), monocyte-derived macrophages (MDMs), and peripheral blood monocytes consitutively expressed sfTSLP mRNA. Incubation of HLMs, MDMs, and monocytes with lipopolysaccharide (LPS) or IL-4, but not with IL-13, induced TSLP release from HLMs. LPS, but not IL-4 or IL-13, induced CXCL8 release from HLMs. LPS, IL-4 alone or in combination with IL-13, induced the expression of lfTSLP, but not of sfTSLP from HLMs. Preincubation of HLMs with IL-4, alone or in combination with IL-13, but not IL-13 alone, synergistically enhanced TSLP release from LPS-activated macrophages. By contrast, IL-4, alone or in combination with IL-13, inhibited LPS-induced CXCL8 release from HLMs. Immunoreactive TSLP was detected in lysates of HLMs, MDMs, and monocytes. Incubation of HLMs with TSLP induced the release of proinflammatory (TNF-α), angiogenic (VEGF-A, angiopoietin 2), and lymphangiogenic (VEGF-C) factors. TSLP, TSLPR, and IL-7Rα were expressed in intratumoral and peritumoral areas of human lung cancer. sfTSLP and lfTSLP mRNAs were differentially expressed in peritumoral and intratumoral lung cancer tissues. The TSLP system, expressed in HLMs, MDMs, and monocytes, could play a role in chronic inflammatory disorders including lung cancer.

Pterostilbene suppresses oxidative stress and allergic airway inflammation through AMPK/Sirt1 and Nrf2/HO-1 pathways

Introduction

Pterostilbene (Pts) may be used for allergic asthma treatment. The AMPK/Sirt1 and Nrf2/HO‐1 pathways are potential targets for asthma treatement. However, the relationship between Pts and AMPK/Sirt1 and Nrf2/HO‐1 pathways in asthma is unclear. Herein, we aim to explore the pharmacological effects of Pts on oxidative stress and allergic inflammatory response as well as the mechanism involving AMPK/Sirt1 and Nrf2/HO‐1 pathways.

Methods

Asthma model was established in mice with ovalbumin (OVA). The model mice were treated by different concentrations of Pts. Lung pathological changes were observed through histological staining. In vitro, lipopolysaccharide (LPS)‐stimulated 16HBE cells were treated with Pts. The siAMPKα2, siSirt1 and siNrf2 knockdown, and treatment with compound C, EX‐527 or ML385 were also performed in 16HBE cells. Enzyme‐linked immunosorbent assay was used to detect interleukin‐4 (IL‐4), IL‐13, IL‐5, total and OVA specific immunoglobulin E (IgE), and interferon γ (IFN‐γ). Pneumonography was used to measure the airway hyperreactivity (AHR). Superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) levels were also detected. Immunohistochemistry, Western blot and immunofluorescence were used to measure protein levels.

Results

Pts significantly attenuated lung inflammatory cell infiltration and goblet cell proliferation. Meanwhile, Pts treatment could reduce IL‐4, IL‐13, IL‐5, and IgE (total and OVA specific) levels in the asthma model mice. However, IFN‐γ in bronchoalveolar lavage fluid was elevated. In addition, Pts reduced AHR. We also found that Pts treatment promoted serum SOD and CAT, and reduced MDA. In vitro results showed that Pts treatment promoted iNOS, TNF‐α, COX‐2, IL‐1β, and IL‐6 expressions in 16HBE cells, prolonged G0/G1 phase of the cell cycle, and resulted in a shortened G2M phase. Moreover, we found that Pts promoted the phosphorylation of AMPK in 16HBE, and meanwhile inhibited the increase of ROS induced by LPS. Additionally, Pts treatment inhibited p‐AMPK, Sirt1, Nrf2 and HO‐1, which in turn leads to the alleviation of AMPK/Sirt1 and Nrf2/HO‐1 pathways.

Conclusion

Pts alleviated oxidative stress and allergic airway inflammation via regulation of AMPK/Sirt1and Nrf2/HO‐1 signaling pathways.

Understanding the key issues in the treatment of uncontrolled persistent asthma with type 2 inflammation

Asthma is a complex respiratory disease that varies in severity and response to treatment. Several asthma phenotypes with unique clinical and inflammatory characteristics have been identified. Endotypes, based on distinct molecular profiles, help to further elucidate the heterogeneity within asthma. Type 2 inflammation, involving both the innate (type 2 innate lymphoid cell) and adaptive (T-helper type 2 cells) immune systems, underpins the complex pathophysiology of chronic inflammation in asthma, as well as the presence of comorbid disease (e.g. chronic rhinosinusitis with nasal polyps, allergic rhinitis and atopic dermatitis). Type 2 inflammation is characterised by upregulation of the type 2 cytokines interleukin (IL)-4, IL-5 and IL-13, IgE-mediated release of immune mediators and dysfunction of epithelial or epidermal barriers. Targeting these key proximal type 2 cytokines has shown efficacy in recent studies adopting a personalised approach to treatment using targeted biologics. Elevated levels of biomarkers downstream of type 2 cytokines, including fractional exhaled nitric oxide, serum IgE and blood and sputum eosinophils, have been linked to mechanisms involved in type 2 inflammation. They have the potential to aid diagnosis, and to predict and monitor response to treatment. The objective of this review is to summarise the current understanding of the biology of type 2 inflammation in asthma, examine its influence on type 2 inflammatory comorbidities, and discuss how type 2 inflammatory biomarkers can be harnessed to further personalise treatments in the age of biologic medicines.

Population pharmacokinetic analysis of dupilumab in adult and adolescent patients with asthma

A population pharmacokinetic model was developed using data from healthy subjects and patients with moderate‐to‐severe asthma receiving intravenous or subcutaneous dupilumab doses. A total of nine phase I to phase III studies were pooled (202 healthy subjects and 1912 patients with asthma including 68 adolescents) in the model development. The best model was a two‐compartment model with parallel linear and nonlinear Michaelis–Menten elimination with first order absorption. The PK parameter estimates were distribution volume of central compartment 2.76 L, linear elimination rate 0.0418 1/day, and subcutaneous bioavailability 60.9%. Pharmacokinetics (PK) properties of dupilumab in patients with asthma were determined to be comparable to those of healthy subjects and patients with atopic dermatitis. Only body weight exerts a notable effect explaining between‐subject variability in dupilumab PK, but dose adjustment for weight is not warranted based on results from clinical studies. There is no PK difference between adolescent and adult patients with asthma after correction for body weight.

Gomisin M2 Ameliorates Atopic Dermatitis-like Skin Lesions via Inhibition of STAT1 and NF-κB Activation in 2,4-Dinitrochlorobenzene/Dermatophagoides farinae Extract-Induced BALB/c Mice

The extracts of Schisandra chinensis (Turcz.) Baill. (Schisandraceae) have various therapeutic effects, including inflammation and allergy. In this study, gomisin M2 (GM2) was isolated from S. chinensis and its beneficial effects were assessed against atopic dermatitis (AD). We evaluated the therapeutic effects of GM2 on 2,4-dinitrochlorobenzene (DNCB) and Dermatophagoides farinae extract (DFE)-induced AD-like skin lesions with BALB/c mice ears and within the tumor necrosis factor (TNF)-α and interferon (IFN)-γ-stimulated keratinocytes. The oral administration of GM2 resulted in reduced epidermal and dermal thickness, infiltration of tissue eosinophils, mast cells, and helper T cells in AD-like lesions. GM2 suppressed the expression of IL-1β, IL-4, IL-5, IL-6, IL-12a, and TSLP in ear tissue and the expression of IFN-γ, IL-4, and IL-17A in auricular lymph nodes. GM2 also inhibited STAT1 and NF-κB phosphorylation in DNCB/DFE-induced AD-like lesions. The oral administration of GM2 reduced levels of IgE (DFE-specific and total) and IgG2a in the mice sera, as well as protein levels of IL-4, IL-6, and TSLP in ear tissues. In TNF-α/IFN-γ-stimulated keratinocytes, GM2 significantly inhibited IL-1β, IL-6, CXCL8, and CCL22 through the suppression of STAT1 phosphorylation and the nuclear translocation of NF-κB. Taken together, these results indicate that GM2 is a biologically active compound that exhibits inhibitory effects on skin inflammation and suggests that GM2 might serve as a remedy in inflammatory skin diseases, specifically on AD.

Effects of dupilumab in type 1 neurofibromatosis coexisting with severe atopic dermatitis

Neurofibromatosis type 1 still lacks established treatment options aimed at controlling the progression of neurofibromas as well as effective therapy for the neurogenic itch associated with the disease. We report the case of a 30-year-old Caucasian woman with type 1 neurofibromatosis coexisting with severe refractory atopic dermatitis. Dupilumab, a novel anti-IL-4 receptor alpha monoclonal antibody, the first biologic agent approved for atopic dermatitis, was the drug of choice in this case. We observed remission of atopic dermatitis and a remarkable reduction in the size and swelling of neurofibromas and in the related pruritus, that became evident after one month of treatment. After 18 months of therapy, no new neurofibromas were detected and preexistent lesions showed no increase in size. These findings are consistent with the hypothesis that dupilumab, a potent anti-inflammatory drug, may have a positive effect on type 1 neurofibromatosis by stopping the progression of preexisting neurofibromas and the onset of new lesions.

Gut Microbiota, Probiotics, and Their Interactions in Prevention and Treatment of Atopic Dermatitis: A Review

Atopic dermatitis (AD) is a public health concern and is increasing in prevalence in urban areas. Recent advances in sequencing technology have demonstrated that the development of AD not only associate with the skin microbiome but gut microbiota. Gut microbiota plays an important role in allergic diseases including AD. The hypothesis of the “gut-skin” axis has been proposed and the cross-talk mechanism between them has been gradually demonstrated in the research. Probiotics contribute to the improvement of the intestinal environment, the balance of immune responses, regulation of metabolic activity. Most studies suggest that probiotic supplements may be an alternative for the prevention and treatment of AD. This study aimed to discuss the effects of probiotics on the clinical manifestation of AD based on gut microbial alterations. Here we reviewed the gut microbial alteration in patients with AD, the association between gut microbiota, epidermal barrier, and toll-like receptors, and the interaction of probiotics and gut microbiota. The potential mechanisms of probiotics on alleviating AD via upregulation of epidermal barrier and regulation of immune signaling had been discussed, and their possible effective substances on AD had been explored. This provides the supports for targeting gut microbiota to attenuate AD.

The ammonia oxidizing bacterium Nitrosomonas eutropha blocks T helper 2 cell polarization via the anti-inflammatory cytokine IL-10

The prevalence of atopic diseases has been steadily increasing since the mid twentieth century, a rise that has been linked to modern hygienic lifestyles that limit exposure to microbes and immune system maturation. Overactive type 2 CD4+ helper T (Th2) cells are known to be closely associated with atopy and represent a key target for treatment. In this study, we present an initial characterization of ammonia oxidizing bacteria (AOB) Nitrosomonas eutropha D23, an environmental microbe that is not associated with human pathology, and show AOB effectively suppress the polarization of Th2 cells and production of Th2-associated cytokines (IL-5, IL-13, and IL-4) by human peripheral blood mononuclear cells (PBMC). We show that AOB inhibit Th2 cell polarization not through Th1-mediated suppression, but rather through mechanisms involving the anti-inflammatory cytokine IL-10 and the potential inhibition of dendritic cells, as evidenced by a reduction in Major Histocompatibility Complex Class II (MHC II) and CD86 expression following AOB treatment. This is the first report of immunomodulatory properties of AOB, and provides initial support for the development of AOB as a potential therapeutic for atopic diseases.

Epigenetic Mechanisms in Allergy Development and Prevention

There has been a substantial increase in the incidence and the prevalence of allergic disorders in the recent decades, which seems to be related to rapid environmental and lifestyle changes, such as higher exposure to factors thought to exert pro-allergic effects but less contact with factors known to be associated with protection against the development of allergies. Pollution is the most remarkable example of the former, while less contact with microorganisms, lower proportion of unprocessed natural products in diet, and others resulting from urbanization and westernization of the lifestyle exemplify the latter. It is strongly believed that the effects of environmental factors on allergy susceptibility and development are mediated by epigenetic mechanisms, i.e. biologically relevant biochemical changes of the chromatin carrying transcriptionally-relevant information but not affecting the nucleotide sequence of the genome. Classical epigenetic mechanisms include DNA methylation and histone modifications, for instance acetylation or methylation. In addition, microRNA controls gene expression at the mRNA level. Such epigenetic mechanisms are involved in crucial regulatory processes in cells playing a pivotal role in allergies. Those include centrally managing cells, such as T lymphocytes, as well as specific structural and effector cells in the affected organs, responsible for the local clinical presentation of allergy, e.g. epithelial or airway smooth muscle cells in asthma. Considering that allergic disorders possess multiple clinical (phenotypes) and mechanistic (endotypes) forms, targeted, stratified treatment strategies based on detailed clinical and molecular diagnostics are required. Since conventional diagnostic or therapeutic approaches do not suffice, this gap could possibly be filled out by epigenetic approaches.

Novel Targeted Biological Agents for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a common inflammatory dermatologic disease clinically characterized by intense itch, recurrent eczematous lesions, and a chronic or relapsing disease course. Mild-to-moderate AD can be controlled by using moisturizers and topical immunomodulators such as topical corticosteroids and calcineurin inhibitors. If topical therapies fail, phototherapy and systemic immunosuppressant therapies, such as ciclosporin, methotrexate, and azathioprine, can be considered. However, relapse and side effects could still occur. The pathogenesis of AD involves epidermal barrier dysfunction, skin microbiome abnormalities, and cutaneous inflammation. Inflammatory mediators, such as interleukin (IL)-4, IL-13, IL-31, IL-33, IL-17, IL-23, and thymic stromal lymphopoietin, are involved in AD development. Therefore, a series of biological agents targeting these cytokines are promising approaches for treating AD. Dupilumab is the first biological agent approved for the treatment of AD in patients aged 6 years and older in the United States. Tralokinumab, lebrikizumab, and nemolizumab have also been confirmed to have significant efficacy against AD in phase III or IIb clinical trials. Also, fezakinumab was effective in severe AD patients in a phase IIa trial. However, phase II trials of ustekinumab, tezepelumab, etokimab, secukinumab, and omalizumab have failed to meet their primary endpoints. Phase II trials of GBR 830 and KHK 4083 are ongoing. In general, further studies are needed to explore new therapeutic targets and improve the efficacy of biological agents.

Dupilumab suppresses type 2 inflammatory biomarkers across multiple atopic, allergic diseases

BACKGROUND

Type 2 inflammation is common in numerous atopic/allergic diseases and can be identified by elevated biomarker levels. Dupilumab, a fully human monoclonal antibody, blocks the shared receptor component for interleukin-4 and interleukin-13, key and central drivers of type 2 inflammation.

OBJECTIVE

Assessment of dupilumab effect on type 2 inflammatory biomarkers in atopic dermatitis (AD), asthma, chronic rhinosinusitis with nasal polyps (CRSwNP) and eosinophilic esophagitis (EoE).

METHODS

Data were extracted from three randomized placebo-controlled trials of dupilumab in AD (NCT02277743, N = 671; NCT02277769, N = 708; NCT02260986, N = 740); and one each in asthma (NCT02414854, N = 1902); CRSwNP (NCT02898454, N = 448); and EoE (NCT02379052, N = 47). Biomarkers assessed were serum thymus and activation-regulated chemokine (TARC), plasma eotaxin-3, serum total immunoglobulin E (IgE), serum periostin and blood eosinophil count.

RESULTS

Dupilumab versus placebo significantly suppressed most type 2 inflammatory biomarker levels across all studies/indications where data were assessed. Reductions in serum TARC, plasma eotaxin-3 and serum periostin occurred rapidly, whereas reductions in serum total IgE were more gradual. Across diseases, at the end of treatment, median percentage change from baseline in TARC levels ranged from -24.8% to -88.6% (placebo +2.6% to -53.6%); -38.2% to -51.5% (placebo +8.3% to -0.16%) in eotaxin-3; -24.8% to -76.7% (placebo +8.3% to -4.4%) in total IgE; and -13.6% to -41.1% (placebo +10.1% to -6.94%) in periostin levels. Blood eosinophil responses to dupilumab varied by disease, with minimal changes in AD in the SOLO studies (median percentage change from baseline to end of treatment: 0% [95% CI: -15.8, 0]); transient increases followed by decreases to below-baseline levels in asthma (-14.6% [-20.0, -7.7]) and CRSwNP (-29.4% [-40.0, -16.3]); and significant decreases in EoE (-50.0% [-50.0, -33.3]).

CONCLUSION AND CLINICAL RELEVANCE

Dupilumab reduced levels of type 2 biomarkers across clinical studies in patients with AD, asthma, CRSwNP and EoE.

Pharmacokinetics of Ruxolitinib in Patients with Atopic Dermatitis Treated With Ruxolitinib Cream: Data from Phase II and III Studies

BACKGROUND

Pathogenesis of atopic dermatitis (AD) involves the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway. A cream formulation of ruxolitinib, a potent selective JAK1/JAK2 inhibitor, was developed for topical delivery.

METHOD

Pharmacokinetic data were obtained from three double-blind, vehicle-controlled studies in patients with AD: a phase II study with ruxolitinib cream 0.15%, 0.5%, or 1.5% once daily or 1.5% twice daily (BID), and two phase III studies with 0.75% or 1.5% BID. Effects of baseline characteristics on pharmacokinetics were examined. Correlations were attempted between plasma concentrations and change in hematological parameters over time.

RESULTS

Ruxolitinib plasma concentrations at steady-state (Css) increased with cream strength in a less-than-dose-proportional manner. In the phase III studies, overall mean (standard deviation [SD]) Css after ruxolitinib cream 0.75% and 1.5% BID (23.8 [35.0] and 35.7 [55.0] nM) were a fraction of the half-maximal inhibitory concentration for thrombopoietin-stimulated phosphorylated STAT3 inhibition (281 nM), a JAK/STAT signaling marker. Three covariates were identified for Css: dose, percent body surface area (%BSA) treated, and baseline Investigator's Global Assessment score. Mean (SD) bioavailability of ruxolitinib cream 1.5% BID was 6.22% (7.66%). There were no correlations between Css and any hematological changes except for a transient increase in platelets at week 2.

CONCLUSIONS

Plasma ruxolitinib concentrations after treatment with topical ruxolitinib cream in patients with up to 20% BSA affected by AD are not expected to lead to systemic plasma concentrations that may be associated with adverse effects commonly associated with oral JAK inhibitors. CLINICALTRIALS.GOV: NCT03011892; NCT03745638; NCT03745651.

Efficacy and action mechanisms of a Chinese herbal formula on experimental models of atopic dermatitis

ETHNOPHARMACOLOGICAL RELEVANCE

Atopic dermatitis (AD) is a skin inflammatory disease characterized by erythema, eruption, lichenification and pruritus. Shi Zhen Formula (SZF), an empirical Chinese herbal preparation, has clinical efficacy in relieving the symptoms of AD patients. However, the underlying molecular mechanisms of SZF remained unclear.

AIM OF THE STUDY

We aimed to investigate the anti-AD effects of SZF and elucidate its underlying molecular mechanisms using in vitro and in vivo models of AD.

MATERIALS AND METHODS

High-performance liquid chromatography analysis was performed for quality control of SZF extract. The anti-inflammatory effect of SZF was investigated through evaluating the levels of nitric oxide (NO), chemokines and pro-inflammatory cytokines in the lipopolysaccharide (LPS) stimulated RAW264.7 cells. AD-like skin lesions in female BALB/c mice were induced by 2,4-dinitrochlorobenzene (DNCB). SZF (3.15, 6.30 and 9.45 g/kg) and dexamethasone (5 mg/kg) were administered by gavage daily for 15 consecutive days. The body weight, skin thickness, skin dermatitis severity and scratching behaviors were recorded throughout the study. Histological analysis, reverse transcription-quantitative polymerase chain reaction (RT-PCR), western blot (WB) and ELISA analysis were used to illuminate the molecular targets associated with the anti-AD effects of SZF.

RESULTS

SZF markedly decreased the epidermal thickening and infiltration of mast cells in the ears and dorsal skin of the 2,4-dinitrochlorobenzene (DNCB)-treated mice. SZF not only suppressed the levels of immunoglobulin E (IgE), histamine, thymic stromal lymphopoietin (TSLP) and IL-4 in the serum but also suppressed the over-production of IL-4 and IL-6 and gene expressions of IL-4, IL-13, IL-31 and TSLP in the dorsal skin. Moreover, SZF improved epidermal barrier by increasing the protein expressions of filaggrin, involucrin and loricrin and inhibited the activation of NF-κB p65 pathway in the dorsal skin of the DNCB-treated mice.

CONCLUSION

SZF alleviates DNCB induced AD-like skin lesions in mice through regulating Th1/Th2 balance, improving epidermal barrier and inhibiting skin inflammation. Our research findings provide scientific footing on the use of this Chinese herbal formula for the treatment of AD.