Dupilumab is a monoclonal antibody approved for the treatment of atopic dermatitis (AD); however, its effects on molecular, cellular, and immunological levels remain to be elucidated. In this study, blood and dermal interstitial fluid (ISF) from nonlesional (NL) and lesional (L) skin were collected from eight patients with moderate to severe AD, before (visit 2-v2) and at the end of a 16-week treatment with dupilumab (visit 10-v10). Clinical treatment effect was demonstrated by significantly decreased AD severity scores at the end of treatment. At v10 versus v2, the percentages of CD4+ interleukin-producing cells showed a decreasing trend in ISF L and NL, unbound IL-4 levels in plasma were increased, IL-5 levels in ISF L reduced, and levels of factors involved in anti-inflammatory pathways and re-epithelization increased. At v2, ISF L showed that AD lesions might have altered amino acid pathways and lipid signaling compared to ISF NL. At v10, ISF L exhibited raised levels of long- and very-long-chain fatty acids and lipids compared to v2. Furthermore, dupilumab administration caused reduced expression of miR-155-5p and miR-378a-3p in ISF L. In conclusion, results from the present study provided novel knowledge by linking local immune and metabolic alterations to AD pathogenesis and treatment response.

BACKGROUND:Using accurate, sensitive, reproducible and efficient in vivo cutaneous pharmacokinetics (PK)-based bioequivalence (BE) approaches can promote the development of topical generic drug products. A clinical dermal open flow microperfusion (dOFM) study has previously demonstrated the BE of topical drug products containing a hydrophilic drug. However, the utility of dOFM to evaluate the topical BE of drug products containing moderately lipophilic drugs, more representative of most topical drugs, has not yet been established. OBJECTIVE:To evaluate the ability of a clinical dOFM study to assess BE of topical products containing two moderately lipophilic drugs that have only minor differences in chemical and physical properties. METHODS:The study included 20 healthy subjects. Four application sites on each thigh were treated with fixed dose lidocaine/prilocaine combination products, and dermal drug concentrations were monitored with two dOFM probes per application site for 12 h. A reference cream was compared to itself and to an approved generic cream (both serving as positive controls for BE), and to a gel (negative control). BE was established based on AUC0to12h and Cmax using the scaled-average-BE approach. Systemic exposure of both drugs was assessed throughout the study. RESULTS:BE was successfully demonstrated for the positive controls, and not for the negative control, for both drugs. The systemic exposure of both drugs was negligible. CONCLUSIONS:dOFM accurately demonstrated BE between bioequivalent topical creams, sensitively discriminated between different formulations and differentiated the cutaneous PK of both study drugs, even though they differ only slightly in chemical and physical properties. These results support the utility of dOFM as a cutaneous PK-based BE approach for topical lipophilic drugs, including lidocaine and prilocaine.

The clinical efficacy of dupilumab for treatment of atopic dermatitis (AD) has been proven in several clinical studies. Being an IL4 receptor alpha antagonist dupilumab inhibits IL4- and IL13-signaling. However, the affected mechanisms and differential effects in the dermis compared to blood are not well understood as most studies have been conducted with plasma. Dermal open flow microperfusion (dOFM) provides the unique possibility to collect interstitial fluid (ISF) directly from the dermis and to assess the whole spectrum of ISF components such as cytokines and immune cells. Therefore, we aimed to evaluate the feasibility of dOFM to assess local tissue response after dupilumab treatment by measuring cytokine concentrations and immune cell populations in dermal ISF of lesional and non-lesional skin of AD patients. This exploratory clinical study involved eight patients with moderate to severe AD. Before and after 16 weeks of biweekly dupilumab injections, different cytokines and immune cell populations were assessed from plasma and ISF samples. ISF was collected from lesional and non-lesional skin using dOFM. Clinical treatment effects were assessed using the clinical scores SCORAD, EASI, IGA. Several cytokines such as IL33, IL1B, CXCL8 were quantifiable in ISF, whereas in plasma they were below the lower limit of quantification. Post-treatment IL4 concentrations were increased in plasma and in dermal ISF as a result of blocked receptors, while post-treatment IL5 concentrations, with IL5 being a downstream biomarker from IL4, were decreased only in lesional skin. Immune cell population analysis showed trends reflecting those of cytokines. Clinical scores were significantly smaller post-treatment, confirming the observed immune cell and cytokine changes of dupilumab. In conclusion, results showed that dOFM was able to monitor local tissue response after dupilumab treatment, thus contributing to gain insights into the mechanism of action of dupilumab. The trial was funded by Sanofi (SGZ-2018-12008).

Psoriasis is a well characterized interleukin (IL)-17A-driven skin disease with neutrophil infiltration and epidermal hyperkeratosis. Several biomarkers, most prominently β-defensin-2 (BD-2), have been identified using local andsystemic invasive measurements as responsive markers of IL-17A-driven skin pathology. We sought to determinewhether measurements of epidermal proteins by tape stripping could offer a minimally-invasive method to assess treatment responses. We compared the expression of 170 proteins in the epidermis (tape stripping) and dermis (open flowmicroperfusion) of 8 psoriatic subjects before and after administration of a single dose of subcutaneous (s.c.) antiIL-17A mAb secukinumab. Proteomic analyses of tape strips revealed a >3-fold decrease in 32 epidermal and inflammatory cell proteins in response to secukinumab. The epidermal proteins with the largest (>10-fold) decreases were: matrix metalloproteinase-8 (MMP-8, 15.68-fold, p<0.05); myeloperoxidase (MPO, 14.72-fold, p<0.005); IL-8 (11.93-fold, p<0.05); MMP-9 (10.81-fold, p<0.005); and IL-1β (10.35-fold, p<0.05). For these proteins, greater-fold protein changes were detected in the epidermis compared to dermis. Immunohistochemical analysis confirmed that neutrophils are the predominant cell type in psoriatic skin lesions that express MPO, MMP-8 and MMP-9, and that secukinumab treatment dramatically decreases neutrophil accumulation. Thus, tape stripping may be used to assess epidermal neutrophils, and protein biomarker responses to anti-IL-17A therapy in psoriasis.

Dupilumab is a monoclonal antibody approved for the treatment of atopic dermatitis (AD). Currently, knowledge linking local metabolic alterations to AD pathogenesis and treatment response remains limited. In this study, dermal open flow microperfusion (dOFM) technology was used to sample dermal interstitial fluid (ISF) of 8 patients with moderate to severe AD, at baseline and after a 16-week treatment with dupilumab. The clinical treatment effect was demonstrated by a significant reduction in Eczema Area and Severity Index score (p<0.001). ISF collected from non-lesional (NL) and lesional (L) skin was comprehensively analyzed for metabolites using liquid chromatography-high resolution mass spectrometry. At baseline, ISF-L showed increased levels of metabolites connected with filaggrin breakdown, glutaminolysis (glutamic acid and 2-oxoglutaric acid), tryptophan metabolism (regulated by pro-inflammatory mediators), disturbances in fatty acid biosynthesis and signaling in inflammation. After treatment, the metabolic patterns in ISF-L reflected improvement of skin barrier. The depletion of pyrimidine nucleotides (such as deoxyuridine) indicates decreased keratinocyte apoptosis. Increased bilirubin relates to reduced oxidative stress; Increased levels of saturated fatty acids relate to decreased beta-oxidation. In ISF-NL, decreased glycerol is associated with an increased production of triglycerides, which are essential to improve skin barrier function. Decreased LysoPE 18:1 and arachidonic acid suggest the suppression of pro-inflammatory pathways after treatment. In both ISF-L and ISF-NL, the most remarkable metabolic changes after treatment were elevated levels of long/very long-chain and unsaturated free fatty acids and lipids (mainly, several phosphatidylcholine and sphingomyelin species). This upregulation of lipid synthesis corresponds to an increased demand for structural molecules needed for the restructuring of stratum corneum lipid matrix and the growth of new keratinocytes. In conclusion, the present investigation contributes to a deeper understanding of the metabolic mechanisms induced by dupilumab treatment and their association (p<0.05) with the observed AD amelioration. This study was supported by Sanofi (SGZ-2018-12008).

Einleitung Die Kombination aus Atezolizumab und Bevacizumab (Atezo/Bev) erwies sich bei Patienten mit hepatozellulärem Karzinom (HCC) als überlegen gegenüber dem Tyrosinkinase-Inhibitor Sorafenib. Eine VEGF-Inhibition ist mit dem Risiko von Blutungen und thromboembolischen Ereignissen verbunden. Atezo/Bev zeigte eine höhere Rate an Blutungen und arteriellen thromboembolischen Ereignissen im Vergleich zu Sorafenib. Lenvatinib ist eine Erstlinienalternative zu Atezo/Bev mit einem längeren progressionsfreien Überleben und einer höheren Ansprechrate als Sorafenib und wird daher oft als Alternative zu Atezo/Bev bevorzugt. Aktuell fehlen jedoch Daten zum Vergleich der Sicherheit von Atezo/Bev zu Lenvatinib.

This paper describes a new approach to the early-stage optimization of topical products and selection of lead formulation candidates. It demonstrates the application of open flow microperfusion in vitro in conjunction with the Franz diffusion cell to compare time-resolved, 24-hour profiles of diclofenac passive diffusion through all skin layers (including the skin barrier, dermis, and subcutis) resulting from nine topical formulations of different composition. The technique was successfully validated for in vitro sampling of diclofenac in interstitial fluid. A multi-compartmental model integrating the two datasets was analyzed and revealed that the passive diffusion of diclofenac through the dermis and subcutis does not correlate with its diffusion through the skin barrier and cannot be predicted using Franz diffusion cell data alone. The combined application of the two techniques provides a new, convenient tool for product development and selection enabling the comparison of topical formulation candidates and their impact on drug delivery through all skin layers. This approach can also generate the experimental data required to improve the robustness of mechanistic PBPK models, and when combined with clinical sampling via open flow microperfusion - for the development of better in vivo-in vitro correlative models.

GlucoTab@MobileCare, a digital workflow and decision support system with integrated basal and basal-plus insulin algorithm was investigated for user acceptance, safety and efficacy in persons with type 2 diabetes receiving home health care by nurses. During a three months study nine participants (five female, age 77 ± 10 years, HbA1c 60 ± 13 mmol/mol (study start) vs. 57 ± 12 mmol/mol (study end) received basal or basal-plus insulin therapy as suggested by the digital system. In total 95% of all suggested tasks (blood glucose (BG) measurements, insulin dose calculations, insulin injections) were performed according to the digital system. Mean morning BG was 171 ± 68 mg/dL in the first study month vs. 145 ± 35 mg/dL in the last study month, indicating a reduced glycemic variability of 33 mg/dL (standard deviation). No hypoglycemic episode < 54 mg/dL occurred. User’s adherence was high and the digital system supported a safe and effective treatment. Larger scale studies are needed to confirm findings under routine care. German Clinical Trials Register ID DRKS00015059

Background Wir untersuchten die Wirksamkeit und Sicherheit einer erneuten Behandlung mit Immun-Checkpoint-Inhibitoren (ICI) bei PatientInnen mit hepatozellulärem Karzinom (HCC), die in einer vorangegangenen systemischen Linie eine ICI-basierte Therapie erhalten hatten.

The aim was to evaluate whether an in vitro release test (IVRT) could differentiate the release rates from five pharmaceutically equivalent acyclovir cream products and one ointment compared to that from a reference product, Zovirax cream (USA), to identify a test product with an inequivalent drug release rate that could serve as negative control for bioequivalence (BE) in a separate in vivo study. The reference product showed equivalent drug release rates compared to itself. The six test products failed to show equivalent drug release rates compared to the reference product. Aciclovir 1A pharma cream was selected to serve as a negative control for subsequent BE studies, since it exhibited the greatest difference in release rate among all creams, compared to the reference product. The results of this study indicate that IVRT results can be highly sensitive and may discriminate clinically relevant differences between products. Results from an appropriately validated IVRT method can support a demonstration of BE by showing that the drug release rates from test and reference products are statistically equivalent, mitigating the risk that differences may exist between the products which may influence in vivo performance of the drug product.

Assessment of percutaneous drug penetration is highly relevant for the development of dermal topical drug products, as these drug products aim to penetrate the skin, deliver a therapeutically effective drug concentration, and exert a local effect. Dose–response assessment, which requires the availability of pharmacokinetics (PK) profiles, is therefore a key step in drug development. Dermal PK can be mapped by sampling and analyzing dermal interstitial fluid (ISF). ISF represents the immediate environment of cells and serves as a transport medium for nutrients, signaling molecules, and for waste products among cells, as well as blood and cells. Techniques to monitor percutaneous drug penetration and to assess dermal PK data by extracting and analyzing dermal ISF samples include a range of models and may be applied ex vivo and in vivo. Dermal ISF can be collected using wicks or capsules implanted into tissue.

Traditionally, cutaneous drug delivery is studied by skin accumulation or skin permeation, while alternative techniques may enable the interactions between the drug and the skin to be studied in more detail. Time-resolved skin profiling for pharmacokinetic monitoring of two Janus Kinase (JAK) inhibitors, tofacitinib and LEO 37319A, was performed using dermal open-flow microperfusion (dOFM) for sampling of perfusate in an ex vivo and in vivo setup in pig skin. Additionally, matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI) was performed to investigate depth-resolved skin distributions at defined time points ex vivo in human skin. By dOFM, higher skin concentrations were observed for tofacitinib compared to LEO 37319A, which was supported by the lower molecular weight, higher solubility, lipophilicity, and degree of protein binding. Using MALDI-MSI, the two compounds were observed to show different skin distributions, which was interpreted to be caused by the difference in the ability of the two molecules to interact with the skin compartments. In conclusion, the techniques assessed time- and depth-resolved skin concentrations and were able to show differences in the pharmacokinetic profiles of two JAK inhibitors. Thus, evidence shows that the two techniques can be used as complementary methods to support decision making in drug development.