Lesional skin of seborrheic dermatitis patients is characterized by skin barrier dysfunction and correlating alterations in the stratum corneum ceramide composition

Seborrheic dermatitis (SD) is a chronic inflammatory skin disease characterized by erythematous papulosquamous lesions in sebum rich areas such as the face and scalp. Its pathogenesis appears multifactorial with a disbalanced immune system, Malassezia driven microbial involvement and skin barrier perturbations. Microbial involvement has been well described in SD, but skin barrier involvement remains to be properly elucidated. To determine whether barrier impairment is a critical factor of inflammation in SD alongside microbial dysbiosis, a cross-sectional study was performed in 37 patients with mild-to-moderate facial SD. Their lesional and non-lesional skin was comprehensively and non-invasively assessed with standardized 2D-photography, optical coherence tomography (OCT), microbial profiling including Malassezia species identification, functional skin barrier assessments and ceramide profiling. The presence of inflammation was established through significant increases in erythema, epidermal thickness, vascularization and superficial roughness in lesional skin compared to non-lesional skin. Lesional skin showed a perturbed skin barrier with an underlying skewed ceramide subclass composition, impaired chain elongation and increased chain unsaturation. Changes in ceramide composition correlated with barrier impairment indicating interdependency of the functional barrier and ceramide composition. Lesional skin showed significantly increased Staphylococcus and decreased Cutibacterium abundances but similar Malassezia abundances and mycobial composition compared to non-lesional skin. Principal component analysis highlighted barrier properties as main discriminating features. To conclude, SD is associated with skin barrier dysfunction and changes in the ceramide composition. No significant differences in the abundance of Malassezia were observed. Restoring the cutaneous barrier might be a valid therapeutic approach in the treatment of facial SD.

Treatment with the Topical Antimicrobial Peptide Omiganan in Mild-to-Moderate Facial Seborrheic Dermatitis versus Ketoconazole and Placebo: Results of a Randomized Controlled Proof-of-Concept Trial

Facial seborrheic dermatitis (SD) is an inflammatory skin disease characterized by erythematous and scaly lesions on the skin with high sebaceous gland activity. The yeast Malassezia is regarded as a key pathogenic driver in this disease, but increased Staphylococcus abundances and barrier dysfunction are implicated as well. Here, we evaluated the antimicrobial peptide omiganan as a treatment for SD since it has shown both antifungal and antibacterial activity. A randomized, patient- and evaluator-blinded trial was performed comparing the four-week, twice daily topical administration of omiganan 1.75%, the comparator ketoconazole 2.00%, and placebo in patients with mild-to-moderate facial SD. Safety was monitored, and efficacy was determined by clinical scoring complemented with imaging. Microbial profiling was performed, and barrier integrity was assessed by trans-epidermal water loss and ceramide lipidomics. Omiganan was safe and well tolerated but did not result in a significant clinical improvement of SD, nor did it affect other biomarkers, compared to the placebo. Ketoconazole significantly reduced the disease severity compared to the placebo, with reduced Malassezia abundances, increased microbial diversity, restored skin barrier function, and decreased short-chain ceramide Cer[NSc34]. No significant decreases in Staphylococcus abundances were observed compared to the placebo. Omiganan is well tolerated but not efficacious in the treatment of facial SD. Previously established antimicrobial and antifungal properties of omiganan could not be demonstrated. Our multimodal characterization of the response to ketoconazole has reaffirmed previous insights into its mechanism of action.

Clinical translation of anti-inflammatory effects of Prevotella histicola in Th1, Th2, and Th17 inflammation

Introduction

EDP1815 is a non-colonizing pharmaceutical preparation of a single stain of Prevotella histicola isolated from the duodenum of a human donor. We report here preclinical and clinical studies showing that the action of EDP1815, an orally delivered and gut restricted single strain of commensal bacteria can regulate inflammatory responses throughout the body.

Methods

Supported by evidence for anti-inflammatory activity in three preclinical mouse models of Th1-, TH2-, and Th17-mediated inflammation, EDP1815 was tested clinically in three Phase 1b studies in patients with psoriasis, patients with atopic dermatitis, and healthy volunteers in a KLH skin challenge model.

Results

Preclinically, EDP1815 was efficacious in all three mouse models of inflammation, showing reduction in skin inflammation as well as related tissue cytokines. In the Phase 1b studies, EDP1815 was found to be well tolerated by participants, with a safety profile comparable to placebo, including no severe or consistent side-effects reported, and no evidence of immunosuppression with no opportunistic infection occurring in these studies. In psoriasis patients, signs of clinical efficacy were seen after 4 weeks of treatment, which continued beyond the treatment period in the higher-dose cohort. In atopic dermatitis patients, improvements were seen throughout the key physician-and patient-reported outcomes. In a healthy-volunteer study of a KLH-induced skin inflammatory response, consistent anti-inflammatory effects were seen in two cohorts through imaging-based measures of skin inflammation.

Discussion

This is the first report demonstrating clinical effects from targeting peripheral inflammation with a non-colonizing gut-restricted single strain of commensal bacteria, providing proof of concept for a new class of medicines. These clinical effects occur without systemic exposure of EDP1815 or modification of the resident gut microbiota, and with placebo-like safety and tolerability. The breadth of these clinical effects of EDP1815, combined with its excellent safety and tolerability profile and oral administration, suggests the potential for a new type of effective, safe, oral, and accessible anti-inflammatory medicine to treat the wide range of diseases driven by inflammation.Clinical Trial Registration: EudraCT # 2018-002807-32; EudraCT # 2018-002807-32; NL8676; https://clinicaltrials.gov/ct2/show/NCT03733353; http://www.trialregister.nl.

A multimodal, comprehensive characterization of a cutaneous wound model in healthy volunteers

Development of pharmacological interventions for wound treatment is challenging due to both poorly understood wound healing mechanisms and heterogeneous patient populations. A standardized and well-characterized wound healing model in healthy volunteers is needed to aid in-depth pharmacodynamic and efficacy assessments of novel compounds. The current study aims to objectively and comprehensively characterize skin punch biopsy-induced wounds in healthy volunteers with an integrated, multimodal test battery. Eighteen (18) healthy male and female volunteers received three biopsies on the lower back, which were left to heal without intervention. The wound healing process was characterized using a battery of multimodal, non-invasive methods as well as histology and qPCR analysis in re-excised skin punch biopsies. Biophysical and clinical imaging read-outs returned to baseline values in 28 days. Optical coherence tomography detected cutaneous differences throughout the wound healing progression. qPCR analysis showed involvement of proteins, quantified as mRNA fold increase, in one or more healing phases. All modalities used in the study were able to detect differences over time. Using multidimensional data visualization, we were able to create a distinction between wound healing phases. Clinical and histopathological scoring were concordant with non-invasive imaging read-outs. This well-characterized wound healing model in healthy volunteers will be a valuable tool for the standardized testing of novel wound healing treatments.

Impact of oral administration of single strain Lactococcus lactis spp. cremoris on immune responses to keyhole limpet hemocyanin immunization and gut microbiota: A randomized placebo-controlled trial in healthy volunteers

Introduction

Lactococcus lactis spp. cremoris has been associated with promising immunomodulatory results in preclinical trials. The aim of this study was to investigate the pharmacodynamic (PD) effects of three monoclonal microbial formulations of L. lactis spp. cremoris (EDP1066) on the immune response to keyhole limpet hemocyanin (KLH). Potential effects on the gut microbiota were also investigated.

Methods

The trial was registered on Netherlands Trial Register (trial ID NL7519, https://trialsearch.who.int). Eighty-one healthy subjects (median 28, range 18-59 years) were randomized to 28 days of enteric-coated capsules at five doses (n = 13) (1.5 * 1012 total cells daily), freeze-dried powder at one dose (n = 12) (3.0 * 1011 total cells daily) or five doses (n = 12), minitablets at one dose (n = 12) or five doses (n = 12), or placebo (n = 20) prior to KLH immunization. Antibody responses and circulating regulatory T cells (Tregs) were measured after KLH immunization, and skin responses were evaluated after a KLH rechallenge by laser speckle contrast imaging and multispectral imaging. Ex vivo lymphocyte (phytohemagglutinin) and monocyte (lipopolysaccharide (LPS)) cytokine release assays were explored in the minitablet-treated groups only. The prevalence of L. lactis spp. cremoris in the gastrointestinal tract and the impact on the fecal microbiota were assessed by qPCR and 16S rRNA sequencing, respectively.

Results

Repeated-measures analysis of covariances revealed no significant treatment effects on the antibody responses to KLH, number of Tregs, or KLH skin rechallenge outcomes. Ex vivo LPS-driven cytokine responses in whole blood were lower in the low dose minitablet group compared to placebo: tumor necrosis factor (estimated difference (ED) from placebo: -44.2%, 95% confidence interval (CI) -65.3% to -10.3%), interleukin (IL)-1β (ED -41.4%, 95% CI -63.5% to -5.8%), and IL-6 (ED -39.2%, 95% CI -56.8% to -14.5%). The fecal presence of L. lactis spp. cremoris increased during treatment by all EDP1066 formulations and normalized 5 days after the last dose. Microbiome α-diversity did not change by the treatments compared to placebo.

Discussion

The EDP1066 formulations did not affect the immune response to KLH immunization in healthy individuals. However, exposure to L. lactis spp. cremoris in minitablet formulation impacted ex vivo whole blood LPS cytokine response. The clinical impact of these effects awaits further investigations.

Netherlands Trial Register

trialsearch.who.int, trial ID NL7519.

OX40L Inhibition Suppresses KLH‐driven Immune Responses in Healthy Volunteers: A Randomized Controlled Trial Demonstrating Proof‐of‐Pharmacology for KY1005

The safety, tolerability, immunogenicity, and pharmacokinetic (PK) profile of an anti‐OX40L monoclonal antibody (KY1005, currently amlitelimab) were evaluated. Pharmacodynamic (PD) effects were explored using keyhole limpet hemocyanin (KLH) and tetanus toxoid (TT) immunizations. Sixty‐four healthy male subjects (26.5 ± 6.0 years) were randomized to single doses of 0.006, 0.018, or 0.05 mg/kg, or multiple doses of 0.15, 0.45, 1.35, 4, or 12 mg/kg KY1005, or placebo (6:2). Serum KY1005 concentrations were measured. Antibody responses upon KLH and TT immunizations and skin response upon intradermal KLH administration were performed. PD data were analyzed using repeated measures analysis of covariances (ANCOVAs) and post hoc exposure‐response modeling. No serious adverse events occurred and all adverse events were temporary and of mild or moderate severity. A nonlinear increase in mean serum KY1005 concentrations was observed (median time to maximum concentration (T_max) ~ 4 hours, geometric mean terminal half‐life (t½) ~ 24 days). Cutaneous blood perfusion (estimated difference (ED) −13.4 arbitrary unit (AU), 95% confidence interval (CI) −23.0 AU to −3.8 AU) and erythema quantified as average redness (ED −0.23 AU, 95% CI −0.35 AU to −0.11 AU) decreased after KY1005 treatment at doses of 0.45 mg/kg and above. Exposure‐response analysis displayed a statistically significant treatment effect on anti‐KLH antibody titers (IgG maximum effect (E_max) −0.58 AU, 95% CI −1.10 AU to −0.06 AU) and skin response (erythema E_max −0.20 AU, 95% CI −0.29 AU to −0.11 AU). Administration of KY1005 demonstrated an acceptable safety and tolerability profile and PK analyses displayed a nonlinear profile of KY1005. Despite the observed variability, skin challenge response after KY1005 treatment indicated pharmacological activity of KY1005. Therefore, KY1005 shows potential as a novel pharmacological treatment in immune‐mediated disorders.

A randomized controlled trial with a delayed-type hypersensitivity model using keyhole limpet haemocyanin to evaluate adaptive immune responses in man

AIMS

Keyhole limpet haemocyanin (KLH) immunization is a clinical model for the evaluation of human antibody responses. The current study evaluated the anti-KLH antibody response after KLH immunization and the delayed-type hypersensitivity response following intradermal KLH administration, using objective imaging techniques.

METHODS

Healthy male subjects aged 24.5 ± 5.4 years were randomized to intramuscular immunization with 100 μg KLH (n = 12) or placebo (n = 3). Anti-KLH antibody (Ig) M and IgG titres were determined before and every 7 days after KLH immunization for a total of 28 days. Twenty-one days after the immunization, all subjects received 1 μg KLH intradermally. Prior to and 2 days after intradermal KLH administration, skin blood perfusion, erythema and oedema were quantified using noninvasive imaging tools. Repeated measures ANCOVAs were used to analyse data.

RESULTS

Anti-KLH IgM and IgG titres increased after KLH immunization compared to placebo (estimated difference [ED]: 37%, 95% confidence interval [CI]: 19-51% and ED: 68%, 95% CI: 56-76% respectively). Upon intradermal KLH administration an increase in skin blood perfusion (ED: 10.9 arbitrary units (AU), 95% CI: 1.4-20.4 AU) and erythema (ED: 0.3 AU, 95% CI: 0.1-0.5 AU) was observed in KLH-immunized subjects compared to placebo.

CONCLUSION

KLH immunization followed by intradermal KLH administration resulted in increased anti-KLH IgM and IgG titres and a delayed-type hypersensitivity response quantified by an increase in skin blood perfusion and erythema. Using noninvasive imaging tools the KLH model has the potential to serve as an objective tool to study the pharmacodynamics of T-cell-directed immunomodulatory drugs.

First Clinical Study with AP30663 - a KCa 2 Channel Inhibitor in Development for Conversion of Atrial Fibrillation

Pharmacological cardioversion of atrial fibrillation (AF) is frequently inefficacious. AP30663, a small conductance Ca²⁺ activated K⁺ (K_Ca2) channel blocker, prolonged the atrial effective refractory period in preclinical studies and subsequently converted AF into normal sinus rhythm. This first‐in‐human study evaluated the safety and tolerability, and pharmacokinetic (PK) and pharmacodynamic (PD) effects were explored. Forty‐seven healthy male volunteers (23.7 ± 3.0 years) received AP30663 intravenously in ascending doses. Due to infusion site reactions, changes to the formulation and administration were implemented in the latter 24 volunteers. Extractions from a 24‐hour continuous electrocardiogram were used to evaluate the PD effect of AP30663. Data were analyzed with a repeated measure analysis of covariance, noncompartmental analysis, and concentration‐effect analysis. In total, 33 of 34 adverse events considered related to AP30663 exposure were related to the infusion site, mild in severity, and temporary in nature, although full recovery took up to 110 days. After formulation and administration changes, the local infusion site reaction remained, but the median duration was shorter despite higher dose levels. AP30663 displayed a less than dose proportional increase in peak plasma concentration (C_max) and a terminal half‐life of around 5 hours. In healthy volunteers, no effect of AP30663 was observed on electrocardiographic parameters, other than a concentration‐dependent effect on the corrected QT Fridericia’s formula interval (+18.8 ± 4.3 ms for the highest dose level compared with time matched placebo). In conclusion, administration of AP30663, a novel K_Ca2 channel inhibitor, was safe and well‐tolerated systemically in humans, supporting further development in patients with AF undergoing cardioversion.

Evaluation of radioiodine therapy in differentiated thyroid cancer subjects with elevated serum thyroglobulin and negative whole body scan using 131I with emphasize on the thallium scintigraphy in these subgroups

OBJECTIVE

Negative diagnostic 131I whole body scans with elevated serum thyroglobulin (Tg) levels are found in 20% of patients with differentiated thyroid cancer (DTC). Empirical radioiodine treatment has been advocated by some researchers, but has had with controversial outcomes. This anterospective study was performed to examine this dilemma and also to determine the capability of thallium (201TI) scintigraphy in these patients.

MATERIALS AND METHODS

A total of 21 patients who had a history of DTC and elevated serum Tg levels, together with a negative diagnostic 131I whole body scans (WBS), were included in the study. All patients underwent posttreatment 131I WBS. Patients with negative posttreatment 131I WBS then underwent 201TI scintigraphy.

RESULTS

The 21 included patients (9 women and 12 men) had a mean age of 53 +/- 14.17 years. The mean pretreatment and posttreatment Tg levels were 227.23 +/- 208.50 ng/ml and 163.43 +/- 282.57 ng/ml, respectively (p value <0.05). Eleven cases showed at least a 50% decrease in Tg value (remission group), 6 patients revealed less than a 50% decrease in Tg value (stable group), while 4 subjects demonstrated an increment in posttreatment Tg relative to pretreatment Tg value (progression group). The cumulative and last 131I doses in the remission, stable, and progression groups were not significantly different (p value >0.05). In the posttreatment 131I WBS, 10 patients showed abnormal findings in their images. In a follow-up scan after 201TI treatment, 7 out of 11 patients had positive scans.

CONCLUSION

The study indicates a positive effect of RAI therapy in DTC patients with elevated Tg and negative 131I WBS. In addition, 201TI scintigraphy can be useful as an alternative modality to improve tumoral detection in this situation and when access to a PET system is limited.

Furazolidone versus metronidazole in quadruple therapy for eradication of Helicobacter pylori in duodenal ulcer disease

OBJECTIVE

Furazolidone, an old but cheap antibiotic, was shown to be a good alternative to metronidazole in triple therapy for Helicobacter pylori eradication in areas where metronidazole resistant bacteria are common, but randomized studies are lacking.

AIM

A randomized controlled trial to determine the efficacy and safety of furazolidone compared to metronidazole in classic quadruple therapy for eradication of H. pylori infection in duodenal ulcer patients.

METHODS

Patients with endoscopically proven duodenal ulcer and positive urease test were randomized to receive ranitidine 300 mg, amoxycillin 1000 mg and bismuth subcitrate 240 mg b.d, with either furazolidone 200 mg b.d (RABF), or metronidazole 500 mg b.d. (RABM) for 2 weeks. Compliance and side-effects were monitored and recorded by table diary. H. pylori eradication was assessed at least 4 weeks after the completion of therapy with 14C-urea breath test.

RESULTS

A total of 106 patients were enrolled and 101 (59 male, 42 female, mean age=40 +/- 11 years) completed the study. Endoscopic findings and demographic data were comparable in both groups. Intention-to-treat eradication rates were 75% and 55% (P=0.03) and per protocol eradication rates were 82 and 56% (P=0. 006) in the RABF and RABM groups, respectively. Side-effects were reported by 13 patients (27%) in the RABF group (one stopped treatment) compared to five patients (10%) in the RABM group (P=0. 04).

CONCLUSION

Quadruple therapy containing furazolidone, instead of metronidazole, results in a significantly higher H. pylori eradication rate in Iranian duodenal ulcer patients.

Hospital discharge policy in thyroid cancer patients treated with 131I: the effect of changing from fixed time to exposure rate threshold

During 1981-1989, a total of 2,238 thyroid carcinoma patients were treated in limited accommodation in Iran with high-fixed ablation or therapeutic doses of 131I . For the 308 patients admitted in 1989, the external body exposure rate was measured sequentially at 2-4 d post-dose administration. Based on the exposure rate of 6.98 C kg(-1) h(-1) (1.8 mR h(-1) at 1 m, cumulative percentages of patients ablated with 3.7 GBq of 131I (268/308) and discharged from the hospital at 2, 3, and 4 d post-dose administration were 75%, 87%, and 95%, respectively. Likewise, for the group treated with 5.55 GBq (31/308), the cumulative percentages of patients discharged by day 2, 3, and 4 were 30%, 68%, and 79%, respectively. In the former, the remaining 5% (13 patients) had the external exposure rate less than 6.98 C kg(-1) h(-1) at one meter, before day seven PDA. In the latter, only 2 patients were released after day seven, that is at day 10, with the exposure rate less than 1.8 mR/hr at one meter. One patient, from the second group, with extensive metastatic disease was discharged at day 14 PDA with the external exposure rate of 5.81 C kg(-1)h(-1)(1.5 mR/hr) at one meter. By applying the above exposure rate as the requirement for the patient discharge, we changed the policy for release of patients from arbitrary 1-wk hospitalization to the discharge at the point when exposure rate dropped below 6.98 C kg(-1)h(-1)(1.8 mR h(-1)) at 1 m, which led to the significant (300%) increase in throughput of patients treated for thyroid carcinoma with 131I, within the same available space limitations.

Trends of population radiation absorbed dose from diagnostic nuclear medicine procedures in Iran: 1985-1989

In view of the rapid expansion of diagnostic nuclear medicine procedures in Iran, this study was undertaken to examine trends of nuclear medicine practice in the country and to determine the mean effective dose equivalent per patient and per capita. Comprehensive national data covering 93% of all nuclear medicine centers in 1985-1989 were obtained. The total number of nuclear medicine examinations increased by 42% during these years. The relative frequency of thyroid investigations was 84% followed by liver/spleen and bone procedures (7% and 6%, respectively). 99mTc was the radionuclide of choice for 86% of investigation while 131I alone accounted for 59% of collective effective dose equivalent. The annual average number of nuclear medicine procedures per 1,000 people was 1.9. For the thyroid, the highest number (48%) of patients investigated was in the 15-29 y age group and the lowest (3%) was in the > 64 y age group. The male to female ratio of thyroid and cardiac patient was 0.18 and 3.64, respectively. The numbers of males and females studied for the remaining eight procedures were less frequent and about the same. The mean effective dose equivalent per patient and per capita was about 4.3 mSv and 8 microSv, respectively. 131I was responsible for most of collective effective dose equivalent produced by nuclear medicine. Therefore, future efforts should be concentrated on dose reduction for diagnostic 131I tests.