Atopic dermatitis (AD) represents the most common skin disease characterized by heterogeneous endophenotypes and a high disease burden. In Europe, six new systemic therapies for AD have been approved: the biologics dupilumab (anti‐interleukin‐4 receptor (IL‐4R) α in 2017), tralokinumab (anti‐IL‐13 in 2021), lebrikizumab (anti‐IL‐13 in 2023), and the oral janus kinase (JAK) inhibitors (JAKi) targeting JAK1/2 (baricitinib in 2020 in the EU) or JAK1 (upadacitinib in 2021 and abrocitinib in 2022). Herein, we give an update on new approvals, long‐term safety, and efficacy. Upadacitinib and abrocitinib have the highest short‐term efficacy among the approved systemic therapies. In responders, dupilumab and tralokinumab catch up regarding long‐term efficacy and incremental clinical benefit within continuous use. Recently, the European Medicines Agency has released recommendations for the use of JAKi in patients at risk (cardiovascular and thromboembolic diseases, malignancies, (former) smoking, and age ≥65 years). Furthermore, we give an overview on emerging therapies currently in Phase III trials. Among the topical therapies, tapinarof (aryl hydrocarbon receptor), ruxolitinib (JAK1/2i), delgocitinib (pan‐JAKi), asivatrep (anti‐transient receptor potential vanilloid), and phosphodiesterase‐4‐inhibitors (roflumilast, difamilast) are discussed. Among systemic therapies, current data on cord‐blood‐derived mesenchymal stem cells, CM310 (anti IL‐4Rα), nemolizumab (anti‐IL‐31RA), anti‐OX40/OX40L‐antibodies, neurokinin‐receptor‐1‐antagonists, and difelikefalin (κ‐opioid‐R) are reported.

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease with a high impact on patients’ quality of life, productivity at work, and burden on the health system, with an increasing cumulative lifetime prevalence of 15% to 28% in industrial nations.^1,2 The pathophysiology is complex and multifactorial. Main mechanistic factors are an altered skin barrier and a modified innate and adaptive immune system, both with a strong genetic background and influenced by gene–environment interactions as well as skin microbiome dysbiosis.^1,3-6

Atopic dermatitis (AD) affects up to 20% of children and is considered the starting point of the atopic march with the development of food allergy, asthma, and allergic rhinitis. The heterogeneous phenotype reflects distinct and/or overlapping pathogenetic mechanisms with varying degrees of epidermal barrier disruption, activation of different T cell subsets and dysbiosis of the skin microbiome. Here, we review current evidence suggesting a systemic impact of the cutaneous inflammation in AD together with a higher risk of asthma and other comorbidities, especially in severe and persistent AD. Thus, early therapy of AD to restore the impaired skin barrier, modified microbiome, and target type 2 inflammation, depending on the (endo)phenotype, in a tailored approach is crucial. We discuss what we can learn from the comorbidities and the implications for preventive and therapeutic interventions from precision dermocosmetics to precision medicine. The stratification of AD patients into biomarker-based endotypes for a precision medicine approach offers opportunities for better long-term control of AD with the potential to reduce the systemic impact of a chronic skin inflammation and even prevent or modify the course, not only of AD, but possibly also the comorbidities, depending on the patient’s age and disease stage.

Background: The heterogeneous (endo)phenotypes of atopic dermatitis (AD) require precision medicine. Currently, systemic therapy is recommended to patients with an Eczema Area and Severity Index (EASI) ≥ 16. Previous studies have demonstrated an improved treatment response to the anti‐interleukin (IL)‐13 antibody tralokinumab in AD subgroups with elevated levels of the IL‐13‐related biomarkers dipeptidyl‐peptidase (DPP)‐4 and periostin. Methods: Herein, 373 AD patients aged ≥12 years were stratified by IL‐13 ^high , periostin ^high and DPP‐4 ^high endotypes using cross‐sectional data from the ProRaD cohort Bonn. “High” was defined as >80th quantile of 47 non‐atopic controls. We analyzed endotype‐phenotype associations using machine‐learning gradient boosting compared to logistic regression. Results: Atopic dermatitis severity and eosinophils correlated with IL‐13 and periostin levels. Correlations of IL‐13 with EASI were stronger in patients with increased (rs = 0.482) than with normal (rs = 0.342) periostin levels. We identified eosinophilia >6% and an EASI range of 5.5–17 dependent on the biomarker combination to be associated with increasing probabilities of biomarker ^high endotypes. Also patients with mild‐to‐low‐moderate severity (EASI < 16) featured increased biomarkers (IL‐13 ^high : 41%, periostin ^high : 48.4%, DPP‐4 ^high : 22.3%). Herthoge sign (adjusted Odds Ratio (aOR) = 1.89, 95% Confidence Interval (CI) [1.14–3.14]) and maternal allergic rhinitis (aOR = 2.79–4.47) increased the probability of an IL‐13 ^high ‐endotype, “dirty neck” (aOR = 2.83 [1.32–6.07]), orbital darkening (aOR = 2.43 [1.08–5.50]), keratosis pilaris (aOR = 2.21 [1.1–4.42]) and perleche (aOR = 3.44 [1.72–6.86]) of a DPP‐4 ^high ‐endotype. Conclusions: A substantial proportion of patients with EASI < 16 featured high biomarker levels suggesting systemic impact of skin inflammation already below the current cut‐off for systemic therapy. Our findings facilitate the identification of patients with distinct endotypes potentially linked to response to IL‐13‐targeted therapy.

The 4th Davos Declaration was developed during the Global Allergy Forum in Davos which aimed to elevate the care of patients with atopic dermatitis (AD) by uniting experts and stakeholders. The forum addressed the high prevalence of AD, with a strategic focus on advancing research, treatment, and management to meet the evolving challenges in the field. This multidisciplinary forum brought together top leaders from research, clinical practice, policy, and patient advocacy to discuss the critical aspects of AD, including neuroimmunology, environmental factors, comorbidities, and breakthroughs in prevention, diagnosis, and treatment. The discussions were geared towards fostering a collaborative approach to integrate these advancements into practical, patient‐centric care. The forum underlined the mounting burden of AD, attributing it to significant environmental and lifestyle changes. It acknowledged the progress in understanding AD and in developing targeted therapies but recognized a gap in translating these innovations into clinical practice. Emphasis was placed on the need for enhanced awareness, education, and stakeholder engagement to address this gap effectively and to consider environmental and lifestyle factors in a comprehensive disease management strategy. The 4th Davos Declaration marks a significant milestone in the journey to improve care for people with AD. By promoting a holistic approach that combines research, education, and clinical application, the Forum sets a roadmap for stakeholders to collaborate to improve patient outcomes in AD, reflecting a commitment to adapt and respond to the dynamic challenges of AD in a changing world.

Background: Atopic dermatitis (AD) and psoriasis vulgaris (PV) are almost mutually exclusive diseases with different immune polarizations, mechanisms and therapeutic targets. Switches to the other disease (“Flip‐Flop” [FF] phenomenon) can occur with or without systemic treatment and are often referred to as paradoxical reactions under biological therapy.Methods: The objective was to develop a diagnostic algorithm by combining clinical criteria of AD and PV to identify FF patients. The algorithm was prospectively validated in patients enrolled in the CK‐CARE registry in Bonn, Germany. Afterward, algorithm refinements were implemented based on machine learning.Results: Three hundred adult Caucasian patients were included in the validation study (n = 238 with AD, n = 49 with PV, n = 13 with FF; mean age 41.2 years; n = 161 [53.7%] female). The total FF scores of the PV and AD groups differed significantly from the FF group in the validation data (p < .001). The predictive mean generalized Youden‐Index of the initial model was 78.9% [95% confidence interval 72.0%–85.6%] and the accuracy was 89.7%. Disease group‐specific sensitivity was 100% (FF), 95.0% (AD), and 61.2% (PV). The specificity was 89.2% (FF), 100% (AD), and 100% (PV), respectively.Conclusion: The FF algorithm represents the first validated tool to identify FF patients.