Unraveling heterogeneity in pediatric atopic dermatitis: Identification of serum biomarker based patient clusters.

BACKGROUND: Increasing evidence shows that pediatric atopic dermatitis (AD) differs from adult AD on a biologic level. Broad biomarker profiling across a wide range of ages of pediatric patients with AD is lacking. OBJECTIVE: Our aim was to identify serum biomarker profiles in children with AD aged 0 to 17 years and compare these profiles with those previously found in adults with AD. METHODS: Luminex multiplex immunoassays were used to measure 145 biomarkers in serum from 240 children with AD (aged 0-17 years). Principal components analysis followed by unsupervised k-means clustering were performed to identify patient clusters. Patients were stratified into age groups (0-4 years, 5-11 years, and 12-17 years) to assess association between age and cluster membership. RESULTS: Children aged 0 to 4 years had the highest levels of TH1 cell-skewing markers and lowest levels of TH17 cell-related markers. TH2 cell-related markers did not differ significantly between age groups. Similar to the pattern in adults, cluster analysis identified 4 distinct pediatric patient clusters (TH2 cell/retinol-dominant, skin-homing-dominant, TH1 cell/TH2 cell/TH17 cell/IL-1-dominant, and TH1 cell/IL-1/eosinophil-inferior clusters). Only the TH1 cell/TH2 cell/TH17 cell/IL-1-dominant cluster resembled 1 of the previously identified adult clusters. Although no association with age or age of onset seemed to be found, disease severity was significantly associated with the skin-homing-dominant cluster. CONCLUSION: Four distinct patient clusters based on serum biomarker profiles could be identified in a large cohort of pediatric patients with AD, of which 1 was similar to previously identified adult clusters. The identification of endotypes driven by distinct underlying immunopathologic pathways might be useful to define pediatric patients with AD who are at risk of persistent disease and may necessitate different targeted treatment approaches.

Confirmation of multiple endotypes in atopic dermatitis based on serum biomarkers.

BACKGROUND: Atopic dermatitis (AD) is a highly heterogeneous disease, both clinically and biologically, whereas patients are still being treated according to a "one-size-fits-all" approach. Stratification of patients into biomarker-based endotypes is important for future development of personalized therapies. OBJECTIVE: Our aim was to confirm previously defined serum biomarker-based patient clusters in a new cohort of patients with AD. METHODS: A panel of 143 biomarkers was measured by using Luminex technology in serum samples from 146 patients with severe AD (median Eczema Area and Severity Index = 28.3; interquartile range = 25.2-35.3). Principal components analysis followed by unsupervised k-means cluster analysis of the biomarker data was used to identify patient clusters. A prediction model was built on the basis of a previous cohort to predict the 1 of the 4 previously identified clusters to which the patients of our new cohort would belong. RESULTS: Cluster analysis identified 4 serum biomarker-based clusters, 3 of which (clusters B, C, and D) were comparable to the previously identified clusters. Cluster A (33.6%) could be distinguished from the other clusters as being a "skin-homing chemokines/IL-1R1-dominant" cluster, whereas cluster B (18.5%) was a "TH1/TH2/TH17-dominant" cluster, cluster C (18.5%) was a "TH2/TH22/PARC-dominant" cluster, and cluster D (29.5%) was a "TH2/eosinophil-inferior" cluster. Additionally, by using a prediction model based on our previous cohort we accurately assigned the new cohort to the 4 previously identified clusters by including only 10 selected serum biomarkers. CONCLUSION: We confirmed that AD is heterogeneous at the immunopathologic level and identified 4 distinct biomarker-based clusters, 3 of which were comparable with previously identified clusters. Cluster membership could be predicted with a model including 10 serum biomarkers.

Dupilumab shows long-term effectiveness in a large cohort of treatment-refractory atopic dermatitis patients in daily practice: 52-Week results from the Dutch BioDay registry.

BACKGROUND: Real-life data on long-term effectiveness and safety of dupilumab in atopic dermatitis patients are limited. OBJECTIVE: To study 52-week effectiveness and safety of dupilumab in a prospective multicenter cohort of adult patients with treatment-refractory atopic dermatitis. METHODS: Patients treated with dupilumab and participating in the Dutch BioDay registry were included. Clinical effectiveness and safety were evaluated. RESULTS: Two hundred ten atopic dermatitis patients were included. Mean percentage change in Eczema Area and Severity Index score after 16 weeks was -70.0% (standard deviation 33.2%) and further decreased to -76.6% (standard deviation 30.6%) by week 52. A greater than or equal to 75% improvement in the score was achieved by 59.9% of individuals by week 16 and by 70.3% by week 52. The most reported adverse effect was conjunctivitis (34%). Limited patients (17; 8.1%) discontinued dupilumab treatment. LIMITATIONS: Because of the lack of a control group and observational design, factors of bias may have been induced. CONCLUSION: Treatment with dupilumab resulted in a rapid improvement in clinical outcome measures, and effectiveness further improved during the 52-week follow-up period.

Rapid and Sustained Effect of Dupilumab on Work Productivity in Patients with Difficult-to-treat Atopic Dermatitis: Results from the Dutch BioDay Registry.

Dupilumab treatment improves signs, symptoms, and quality of life in patients with moderate-to-severe atopic dermatitis. This study evaluated the impact of dupilumab treatment on absenteeism, presenteeism, and related costs in a large multi-centre cohort of adult patients with difficult-to-treat atopic dermatitis in daily practice. Patients treated with dupilumab participating in the Dutch BioDay Registry reporting employment were included. Absenteeism, presenteeism, and related costs at baseline and during follow-up were calculated using the Work Productivity and Activity Impairment questionnaire. A total of 218 adult patients with moderate-to-severe atopic dermatitis were included. Total work impairment reduced significantly from baseline (35.5%) to week 52 (11.5%), p < 0.001. Median weekly productivity losses reduced significantly from baseline (€379.8 (140.7-780.8)) to week 52 (€0.0 (0.0-211.0), p < 0.001). In this study, dupilumab treatment demonstrated a significant improvement in work productivity and reduction in associated costs in a large cohort of patients with difficult-to-treat atopic dermatitis in daily practice.

Dupilumab is very effective in a large cohort of difficult-to-treat adult atopic dermatitis patients: First clinical and biomarker results from the BioDay registry.

INTRODUCTION: Dupilumab has recently been approved for the treatment of moderate to severe atopic dermatitis (AD) in adults. Daily practice data on dupilumab treatment are scarce. OBJECTIVE: To study the effect of 16-week treatment with dupilumab on clinical response and serum biomarkers in adult patients with moderate-severe AD in daily practice. METHODS: Data were extracted from the BioDay registry, a prospective multicenter registry. Sixteen-week clinical effectiveness of dupilumab was expressed as number of patients achieving EASI-50 (Eczema Area and Severity Index) or EASI-75, as well as patient-reported outcomes measures (Patient-Oriented Eczema Measure, Dermatology Life Quality Index, Numeric Rating Scale pruritus). Twenty-one biomarkers were measured in patients treated with dupilumab without concomitant use of oral immunosuppressive drugs at five different time points (baseline, 4, 8, 12, and 16 weeks). RESULTS: In total, 138 patients treated with dupilumab in daily practice were included. This cohort consisted of patients with very difficult-to-treat AD, including 84 (61%) patients who failed treatment on ≥2 immunosuppressive drugs. At week 16, the mean percent change in EASI score was 73%. The EASI-50 and EASI-75 were achieved by 114 (86%) and 82 (62%) patients after 16 weeks of treatment. The most reported side effect was conjunctivitis, occurring in 47 (34%) patients. During dupilumab treatment, disease severity-related serum biomarkers (TARC, PARC, periostin, and IL-22), eotaxin-1, and eotaxin-3 significantly decreased. CONCLUSION: Treatment with dupilumab significantly improved disease severity and decreased severity-related serum biomarkers in patients with very difficult-to-treat AD in a daily practice setting.

Moving toward endotypes in atopic dermatitis: Identification of patient clusters based on serum biomarker analysis.

BACKGROUND: Atopic dermatitis (AD) is a complex, chronic, inflammatory skin disease with a diverse clinical presentation. However, it is unclear whether this diversity exists at a biological level. OBJECTIVE: We sought to test the hypothesis that AD is heterogeneous at the biological level of individual inflammatory mediators. METHODS: Sera from 193 adult patients with moderate-to-severe AD (six area, six sign atopic dermatitis [SASSAD] score: geometric mean, 22.3 [95% CI, 21.3-23.3] and 39.1 [95% CI, 37.5-40.9], respectively) and 30 healthy control subjects without AD were analyzed for 147 serum mediators, total IgE levels, and 130 allergen-specific IgE levels. Population heterogeneity was assessed by using principal component analysis, followed by unsupervised k-means cluster analysis of the principal components. RESULTS: Patients with AD showed pronounced evidence of inflammation compared with healthy control subjects. Principal component analysis of data on sera from patients with AD revealed the presence of 4 potential clusters. Fifty-seven principal components described approximately 90% of the variance. Unsupervised k-means cluster analysis of the 57 largest principal components delivered 4 distinct clusters of patients with AD. Cluster 1 had high SASSAD scores and body surface areas with the highest levels of pulmonary and activation-regulated chemokine, tissue inhibitor of metalloproteinases 1, and soluble CD14. Cluster 2 had low SASSAD scores with the lowest levels of IFN-α, tissue inhibitor of metalloproteinases 1, and vascular endothelial growth factor. Cluster 3 had high SASSAD scores with the lowest levels of IFN-ß, IL-1, and epithelial cytokines. Cluster 4 had low SASSAD scores but the highest levels of the inflammatory markers IL-1, IL-4, IL-13, and thymic stromal lymphopoietin. CONCLUSION: AD is a heterogeneous disease both clinically and biologically. Four distinct clusters of patients with AD have been identified that could represent endotypes with unique biological mechanisms. Elucidation of these endotypes warrants further investigation and will require future intervention trials with specific agents, such as biologics.

ZFP36 Family Members Regulate the Proinflammatory Features of Psoriatic Dermal Fibroblasts.

Dermal fibroblasts are strategically positioned underneath the basal epidermis layer to support keratinocyte proliferation and extracellular matrix production. In inflammatory conditions, these fibroblasts produce cytokines and chemokines that promote the chemoattraction of immune cells into the dermis and the hyperplasia of the epidermis, two characteristic hallmarks of psoriasis. However, how dermal fibroblasts specifically contribute to psoriasis development remains largely uncharacterized. In this study, we investigated through which cytokines and signaling pathways dermal fibroblasts contribute to the inflammatory features of psoriatic skin. We show that dermal fibroblasts from lesional psoriatic skin are important producers of inflammatory mediators, including IL-6, CXCL8, and CXCL2. This increased cytokine production was found to be regulated by ZFP36 family members ZFP36, ZFP36L1, and ZFP36L2, RNA-binding proteins with mRNA-degrading properties. In addition, the expression of ZFP36 family proteins was found to be reduced in chronic inflammatory conditions that mimic psoriatic lesional skin. Collectively, these results indicate that dermal fibroblasts are important producers of cytokines in psoriatic skin and that reduced expression of ZFP36 members in psoriasis dermal fibroblasts contributes to their inflammatory phenotype.

Early and Long-Term Effects of Dupilumab Treatment on Circulating T-Cell Functions in Patients with Moderate-to-Severe Atopic Dermatitis.

Dupilumab, a mAb targeting IL-4 receptor alpha (IL-4Rα), markedly improves disease severity in patients with atopic dermatitis. However, the effect of IL-4Rα blockade on dynamics of circulating skin-homing T cells, which are crucial players in the pathologic mechanism of atopic dermatitis, has not been studied yet. In addition, it remains unknown whether dupilumab treatment induces long-lasting T- and B-cell polarization. Therefore, we studied the short- and long-term effects of dupilumab treatment on IL-4Rα expression and T-cell cytokine production within total and skin-homing (cutaneous lymphocyte antigen+/CCR4+) subpopulations in patients with moderate-to-severe atopic dermatitis. Dupilumab treatment completely blocked IL-4Rα expression and signal transducer and activator of transcription 6 phosphorylation in CD19+ B cells and CD4+ T cells within 2 hours of administration and through week 52. Although no change in the proportion of skin-homing T-cell subsets was found, dupilumab treatment significantly decreased the percentage of proliferating (Ki67+) and T helper type 2 and T helper type 22 cytokine-producing skin-homing CD4+ T cells at week 4. No evidence of general T helper type cell skewing following a year of dupilumab treatment was found. In summary, dupilumab treatment rapidly and stably inhibited IL-4Rα, which was accompanied by a strong early functional immunological effect specifically on skin-homing T cells without affecting overall T helper type cell skewing in the long term.

Towards personalized treatment in atopic dermatitis.

INTRODUCTION: For many years, oral immunosuppressive drugs such as cyclosporine A, azathioprine, mycophenolic acid, and methotrexate were the only treatment options, in addition to topical treatment, in patients with severe atopic dermatitis (AD). Dupilumab, a monoclonal antibody targeting the IL-4 receptor alpha, is the first antibody-based treatment commercially available for the treatment of AD. In the near future, more antibody-based treatments and small molecules will become available in the treatment of severe AD. AREAS COVERED: This review gives an overview of current and future therapies for severe AD, outlines options to optimize treatment with oral immunosuppressive drugs and gives an insight into the future of personalized treatment in AD. EXPERT OPINION: Due to the heterogeneous character of AD, it is unlikely that all patients will respond equally to these newly tested drugs. We believe that biomarkers will lead to better identification of patients that will benefit from these highly specific, but expensive new treatments. In addition to a role for biomarkers in new treatments, the use of pharmacogenomic biomarkers can improve the efficacy of currently used oral immunosuppressive drugs in AD, which will still be needed for the treatment of moderate to severe AD in the coming years.

Dupilumab after the 2017 approval for the treatment of atopic dermatitis: what's new and what's next?

PURPOSE OF REVIEW: The IL-4/13 antagonist dupilumab was approved in 2017 as the first biologic for atopic dermatitis. Here, we comprehensively review compelling new data regarding dupilumab published following the approval. RECENT FINDINGS: Daily clinical practice reports of dupilumab in atopic dermatitis are favorable and in line with the registration trials. Dupilumab does not appear to negatively affect pharmacokinetics of CYP450-metabolized drugs nor vaccination responses. Type 2 inflammation biomarkers in skin and serum are reduced following dupilumab treatment. Dupilumab increases the risk for conjunctivitis, especially with higher baseline atopic dermatitis severity and a history of conjunctivitis, but the underlying mechanisms are unknown. Favorable effects of dupilumab have been reported in treatment-recalcitrant hand eczema and prurigo nodularis cases; for allergic contact dermatitis and alopecia areata, there are conflicting responses to dupilumab, possible stemming from pathophysiological heterogeneity. SUMMARY: Daily practice data support the continued use of dupilumab for atopic dermatitis. The only safety signal is an increased risk for conjunctivitis; mechanistic studies into dupilumab-associated conjunctivitis should lead to risk mitigation strategies. Prospective, controlled evaluations are needed for dupilumab in hand eczema and prurigo nodularis. A precision medicine-driven drug-development approach is essential to assess dupilumab for diseases with heterogeneous pathophysiologies, such as alopecia areata and allergic contact dermatitis.