Open-Label Interventional Study in Healthy Volunteers to Evaluate NO-Mediated Vasodilation by Dermal Allyl Isothiocyanate Challenge and Whole-Body Heat Stress.

Dermal allyl isothiocyanate (AITC) administration and whole-body heat stress (WBHS) are two challenge models that are used to evaluate physiological mechanisms of vasodilation and pharmacological activity in humans. Their exact vasodilatory mechanisms in humans are not fully elucidated but are likely to be nitric oxide (NO)-mediated. This study aimed to evaluate whether there is overlap in the vasodilatory pathways of dermal AITC application and WBHS by combining the challenges. In this open-label interventional study, healthy volunteers underwent dermal administration of AITC twice: under basal conditions and during WBHS. Dermal blood flow (DBF) was non-invasively measured using laser speckle contrast imaging four times, once in each of the following situations: baseline, WBHS only, AITC only, and WBHS combined with AITC. A total of 12 male volunteers, aged 18-61 years, participated in the study. Compared to baseline, following AITC application, their DBF increased by 63.43 AU (baseline: 32.55, 95% CI [17.78, 47.31] AU, AITC only: 95.97, 95% CI [81.21, 110.7] AU, p < 0.0001). During WBHS, the increase in DBF after AITC was 42.76 AU (WBHS only: 87.25, 95% CI [72.49, 102.0] AU, WBHS+AITC: 130.0, 95% CI [115.2, 144.8] AU, p < 0.0001). The combination of WBHS and AITC resulted in a lower DBF than the sum of the DBF responses to AITC and WBHS when applied separately (ED 20.67, 95% CI [-3.532, 44.88], p = 0.0916). This might point towards the presence of an interaction in the vasodilatory mechanism of AITC application and WBHS, possibly indicating overlap in their NOS-driven vasodilatory pathways.

Microvascular effects of a mixed meal tolerance test: a model validation study.

PURPOSE: Endothelial dysfunction is a pathophysiological change preceding many cardiovascular events. Measuring improvements of endothelial function is challenging when function is already optimal, which may be remediated using a physiological challenge. This study aimed to determine whether imaging assessments can detect microvascular effects of a mixed meal tolerance test (MMTT). METHODS: Twenty healthy volunteers (age ≥45 and ≤70 years) underwent two MMTTs at the beginning (Day 1) and end (Day 84) of a twelve-week period. Imaging methods included laser speckle contrast imaging (LSCI) combined with post-occlusive reactive hyperaemia (PORH) and local thermal hyperaemia (LTH) challenges, passive leg movement ultrasonography (PLM), and sidestream dark field microscopy (SDFM). Measurements were conducted pre-MMTT and at 5 timepoints post-MMTT for PLM and SDFM and 3 timepoints post-MMTT for PORH and LTH. RESULTS: No consistent effects of the MMTT were detected on LSCI LTH, PLM and SDFM endpoints. LSCI PORH maximum perfusion was significantly suppressed 46, 136, and 300 min post-MMTT administration on Day 1, while residual perfusion decreased significantly 46 and 136 min post-MMTT on Day 1. However, when repeated on Day 84, PORH endpoints were not significantly affected by the MMTT. CONCLUSION: SDFM, PLM and LSCI LTH endpoints displayed high intra-subject variability and did not detect consistent effects of MMTT. LSCI PORH endpoints displayed the lowest intra-subject variability of all assessed endpoints and were affected by the MMTT on Day 1, but not on Day 84. Further standardization of methods or more robust challenges to affect vascular endpoints may be needed.

Guselkumab treatment normalizes the stratum corneum ceramide profile and alleviates barrier dysfunction in psoriasis: results of a randomized controlled trial.

The epidermal inflammation associated with psoriasis drives skin barrier perturbations. The skin barrier is primarily located in stratum corneum (SC). Its function depends on the SC lipid matrix of which ceramides constitute important components. Changes in the ceramide profile directly correlate to barrier function. In this study, we characterized the dynamics of the barrier function and ceramide profile of psoriatic skin during anti-Interleukin-23 therapy with guselkumab. We conducted a double-blind, randomized controlled trial in which 26 mild-to-severe plaque psoriasis patients were randomization 3:1-100 mg guselkumab or placebo for 16 weeks and barrier dynamics monitored throughout. Barrier function was measured by trans-epidermal water loss measurements. Untargeted ceramide profiling was performed using liquid chromatography-mass spectrometry after SC was harvested using tape-stripping. The barrier function and ceramide profile of lesional skin normalized to that of controls during treatment with guselkumab, but not placebo. This resulted in significant differences compared to placebo at the end of the treatment. Changes in the lesional ceramide profile during treatment correlated with barrier function and target lesion severity. Nonlesional skin remained similar throughout treatment. Guselkumab therapy restored the skin barrier in psoriasis. Concomitant correlations between skin barrier function, the ceramide profile, and disease severity demonstrate their interdependency.

Cannabidiol Increases Psychotropic Effects and Plasma Concentrations of Δ9-Tetrahydrocannabinol Without Improving Its Analgesic Properties.

Cannabidiol (CBD), the main non-intoxicating compound in cannabis, has been hypothesized to reduce the adverse effects of Δ9-tetrahydrocannabinol (THC), the main psychoactive and analgesic component of cannabis. This clinical trial investigated the hypothesis that CBD counteracts the adverse effects of THC and thereby potentially improves the tolerability of cannabis as an analgesic. A randomized, double-blind, placebo-controlled, five-way cross-over trial was performed in 37 healthy volunteers. On each visit, a double-placebo, THC 9 mg with placebo CBD, or THC 9 mg with 10, 30, or 450 mg CBD was administered orally. Psychoactive and analgesic effects were quantified using standardized test batteries. Pharmacokinetic sampling was performed. Data were analyzed using mixed-effects model. Co-administration of 450 mg CBD did not reduce, but instead significantly increased subjective, psychomotor, cognitive, and autonomous effects of THC (e.g., VAS "Feeling High" by 60.5% (95% CI: 12.7%, 128.5%, P < 0.01)), whereas THC effects with 10 and 30 mg CBD were not significantly different from THC alone. CBD did not significantly enhance THC analgesia at any dose level. Administration of 450 mg CBD significantly increased AUClast of THC (AUClast ratio: 2.18, 95% CI: 1.54, 3.08, P < 0.0001) and 11-OH-THC (AUClast ratio: 6.24, 95% CI: 4.27, 9.12, P < 0.0001) compared with THC alone, and 30 mg CBD significantly increased AUClast of 11-OH-THC (AUClast ratio: 1.89, 95% CI: 1.30, 2.77, P = 0.0013), and of THC (AUClast ratio: 1.44, 95% CI: 1.01, 2.04, P = 0.0446). Present findings do not support the use of CBD to reduce adverse effects of oral THC or enhance THC analgesia.

Target engagement and immunogenicity of an active immunotherapeutic targeting pathological α-synuclein: a phase 1 placebo-controlled trial.

Investigational therapeutics that target toxic species of α-synuclein (αSyn) aim to slow down or halt disease progression in patients with Parkinson's disease (PD). Here this 44-week, randomized, placebo-controlled, double-blind, single-center phase 1 study investigated safety, tolerability and immunogenicity of UB-312, an active immunotherapeutic targeting pathological αSyn, in patients with PD. The primary outcome measures were adverse event frequency and change in anti-αSyn antibody titers in blood and cerebrospinal fluid (CSF). Exploratory outcomes were changes in clinical scales and biomarker-based target engagement as measured by seed amplification assays. Twenty patients were randomized 7:3 (UB-312:placebo) into 300/100/100 µg or 300/300/300 µg (weeks 1, 5 and 13) intramuscular prime-boost dose groups. Safety was similar across groups; adverse events were mostly mild and transient. Two patients experienced three serious adverse events in total, one possibly treatment related; all resolved without sequalae. Anti-αSyn antibodies in serum from 12/13 and CSF from 5/13 patients who received three UB-312 doses confirmed immunogenicity. Mean serum titers (in log-dilution factor) increased from baseline by 1.398 and 1.354, and peaked at week 29 at 2.520 and 2.133, for 300/100/100 µg and 300/300/300 µg, respectively. CSF titers were 0 at baseline and were 0.182 and 0.032 at week 21, respectively. Exploratory analyses showed no statistical differences in clinical scales but a significant reduction of αSyn seeds in CSF of a subset of UB-312-treated patients. These data support further UB-312 development. ClinicalTrials.gov: NCT04075318 .

The ClC-1 chloride channel inhibitor NMD670 improves skeletal muscle function in rat models and patients with myasthenia gravis.

Myasthenia gravis (MG) is a neuromuscular disease that results in compromised transmission of electrical signals at the neuromuscular junction (NMJ) from motor neurons to skeletal muscle fibers. As a result, patients with MG have reduced skeletal muscle function and present with symptoms of severe muscle weakness and fatigue. ClC-1 is a skeletal muscle specific chloride (Cl-) ion channel that plays important roles in regulating neuromuscular transmission and muscle fiber excitability during intense exercise. Here, we show that partial inhibition of ClC-1 with an orally bioavailable small molecule (NMD670) can restore muscle function in rat models of MG and in patients with MG. In severely affected MG rats, ClC-1 inhibition enhanced neuromuscular transmission, restored muscle function, and improved mobility after both single and prolonged administrations of NMD670. On this basis, NMD670 was progressed through nonclinical safety pharmacology and toxicology studies, leading to approval for testing in clinical studies. After successfully completing phase 1 single ascending dose in healthy volunteers, NMD670 was tested in patients with MG in a randomized, placebo-controlled, single-dose, three-way crossover clinical trial. The clinical trial evaluated safety, pharmacokinetics, and pharmacodynamics of NMD670 in 12 patients with mild MG. NMD670 had a favorable safety profile and led to clinically relevant improvements in the quantitative myasthenia gravis (QMG) total score. This translational study spanning from single muscle fiber recordings to patients provides proof of mechanism for ClC-1 inhibition as a potential therapeutic approach in MG and supports further development of NMD670.

Administration of oxathridine, a first-in-class histamine-3 receptor partial agonist in healthy male volunteers: Central nervous system depression and pseudo-hallucinations.

AIMS: To characterise the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of single ascending doses of oxathridine, a first-in-class histamine-3 receptor partialagonist, in healthy male volunteers. METHODS: A randomised, double-blind, placebo-controlled study including the NeuroCart, consisting of a battery of drug sensitive neurophysiological tests, was performed. Oxathridine was administered orally as an aqueous solution. After dosing, safety and NeuroCart tests (adaptive tracking [AT], body sway [BS], saccadic peak velocity [SPV], smooth pursuit [SP] eye movements, VAS according to Bond and Lader, VAS according to Bowdle [VAS B&L, Bowdle], pharmaco-electroencephalogram [pEEG], Sustained Attention to Response Task [SART]) were performed at set times. RESULTS: Forty volunteers completed the study. Given doses were: 0.5, 2.5, 5, 0.25 and 1.5 mg. At 5 mg, unacceptable and unanticipated adverse events (AEs) of (orthostatic) hypotension and pseudo-hallucinations were reported. Statistically significant effects ([CI]; p-value) of 2.5 mg and 5 mg oxathridine were observed on AT ([-8.28, -1.60]; p = 0.0048), ([-8.10, -1.51]; p = 0.00530), BS ([0.6, 80.2]; p = 0.0455), ([5.9, 93.1]; p = 0.0205) and SPV ([-59.0, -15.9]; p = 0.0011), ([-43.9, -1.09]; p = 0.0399), respectively. Oxathridine 5 mg significantly increased all three VAS Bowdle subscale scores; VAS external ([0.183, 0.476]; p = <.0001), VAS internal ([0.127, 0.370]; p = 0.0001) and VAS feeling high ([0.263, 0.887]; p = 0.0006). CONCLUSION: NeuroCart tests indicated central nervous system (CNS) depressant effects. Oxathridine also unexpectedly caused pseudohallucinations. Although this led to the decision to stop further development of oxathridine, these observations suggest that the H3R system could be an interesting new target for the development of novel antipsychotics.

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.

Oral prednisolone suppresses skin inflammation in a healthy volunteer imiquimod challenge model.

Imiquimod (IMQ) is a topical agent that induces local inflammation via the Toll-like receptor 7 pathway. Recently, an IMQ-driven skin inflammation model was developed in healthy volunteers for proof-of-pharmacology trials. The aim of this study was to profile the cellular, biochemical, and clinical effects of the marketed anti-inflammatory compound prednisolone in an IMQ model. This randomized, double-blind, placebo-controlled study was conducted in 24 healthy volunteers. Oral prednisolone (0.25 mg/kg/dose) or placebo (1:1) was administered twice daily for 6 consecutive days. Two days after treatment initiation with prednisolone or placebo, 5 mg imiquimod (IMQ) once daily for two following days was applied under occlusion on the tape-stripped skin of the back for 48 h in healthy volunteers. Non-invasive (imaging and biophysical) and invasive (skin punch biopsies and blister induction) assessments were performed, as well as IMQ ex vivo stimulation of whole blood. Prednisolone reduced blood perfusion and skin erythema following 48 h of IMQ application (95% CI [-26.4%, -4.3%], p = 0.0111 and 95% CI [-7.96, -2.13], p = 0.0016). Oral prednisolone suppressed the IMQ-elevated total cell count (95% CI [-79.7%, -16.3%], p = 0.0165), NK and dendritic cells (95% CI [-68.7%, -5.2%], p = 0.0333, 95% CI [-76.9%, -13.9%], p = 0.0184), and classical monocytes (95% CI [-76.7%, -26.6%], p = 0.0043) in blister fluid. Notably, TNF, IL-6, IL-8, and Mx-A responses in blister exudate were also reduced by prednisolone compared to placebo. Oral prednisolone suppresses IMQ-induced skin inflammation, which underlines the value of this cutaneous challenge model in clinical pharmacology studies of novel anti-inflammatory compounds. In these studies, prednisolone can be used as a benchmark.