Orexin 2 receptor-selective agonist danavorexton improves narcolepsy phenotype in a mouse model and in human patients.

Narcolepsy type 1 (NT1) is a sleep disorder caused by a loss of orexinergic neurons. Narcolepsy type 2 (NT2) is heterogeneous; affected individuals typically have normal orexin levels. Following evaluation in mice, the effects of the orexin 2 receptor (OX2R)-selective agonist danavorexton were evaluated in single- and multiple-rising-dose studies in healthy adults, and in individuals with NT1 and NT2. In orexin/ataxin-3 narcolepsy mice, danavorexton reduced sleep/wakefulness fragmentation and cataplexy-like episodes during the active phase. In humans, danavorexton administered intravenously was well tolerated and was associated with marked improvements in sleep latency in both NT1 and NT2. In individuals with NT1, danavorexton dose-dependently increased sleep latency in the Maintenance of Wakefulness Test, up to the ceiling effect of 40 min, in both the single- and multiple-rising-dose studies. These findings indicate that OX2Rs remain functional despite long-term orexin loss in NT1. OX2R-selective agonists are a promising treatment for both NT1 and NT2.

Orexin 2 receptor-selective agonist danavorexton (TAK-925) promotes wakefulness in non-human primates and healthy individuals.

The orexin 2 receptor-selective agonist danavorexton (TAK-925) has been shown to produce wake-promoting effects in wild-type mice, narcolepsy-model mice, and individuals with narcolepsy type 1 and type 2. Here, we report wake-promoting effects of danavorexton in non-human primates and healthy men during their sleep phase. Electroencephalogram analyses revealed that subcutaneous administration of danavorexton significantly increased wakefulness in common marmosets (p < 0.05 at 0.1 mg kg-1 , and p < 0.001 at 1 mg kg-1 and 10 mg kg-1 ) and cynomolgus monkeys (p ≤ 0.05 at 1 mg kg-1 and 3 mg kg-1 ). In a phase 1b crossover, randomized, double-blind, placebo-controlled and active-controlled study in sleep-deprived healthy participants (ClinicalTrials.gov identifier: NCT03522506), modafinil 300 mg (used to demonstrate assay sensitivity) and continuous infusion of danavorexton 44 mg and danavorexton 112 mg showed statistically superior wake-promoting effects to placebo (n = 18). Measured using the Maintenance of Wakefulness Test, mean (standard deviation) sleep latencies during infusion of danavorexton 44 mg, danavorexton 112 mg and placebo were 21.4 (8.9), 31.8 (3.2) and 9.2 (6.4) min, respectively. Least-squares mean difference from placebo in average sleep latency was 16.8 min with danavorexton 44 mg and 30.2 min with danavorexton 112 mg (both p < 0.001). Karolinska Sleepiness Scale scores were statistically significantly lower (indicating decreased sleepiness) for participants receiving danavorexton than for those receiving placebo during infusion (danavorexton 44 mg, p = 0.010; danavorexton 112 mg, p < 0.001). Together, these results indicate that an orexin 2 receptor agonist increases wakefulness in non-human primates and healthy individuals during their sleep phase.

Structural features of bovine colostral immunoglobulin that confer proteolytic stability in a simulated intestinal fluid.

Bovine colostral antibodies, purified from cow's milk produced immediately after calving, have enhanced resistance to degradation by intestinal proteases relative to antibodies from human or bovine serum, making them of particular interest as orally administered therapeutic agents. However, the basis of this resistance is not well defined. We evaluated the stability of AVX-470, a bovine colostral anti-tumor necrosis factor (TNF) polyclonal antibody used in early clinical studies for treatment of ulcerative colitis, using conditions that mimic the human small intestine. AVX-470 was degraded ∼3 times more slowly than human IgG antibodies or infliximab (a monoclonal mouse-human chimeric IgG). Bovine IgG1 antibodies, the primary component of AVX-470, were slowly cleaved to F(ab')2 fragments. In contrast, bovine IgG2 and human IgG1 antibodies were cleaved rapidly into Fab and smaller fragments, pointing to specific regions where additional stability might be gained. Infliximab was modified to incorporate the sequences from these regions, including the bovine IgG1 hinge region and a predicted disulfide bonding motif linking the upper hinge region, the CH1 domain, and the light chain. This infliximab-bovine IgG1 chimera (bovinized infliximab) retained the antigen binding and neutralization activity of the WT sequence but was degraded 9-fold more slowly than the unmodified infliximab. This remarkable increase in stability with as few as 18 amino acid substitutions suggests that this bovinization process is a means to enable oral delivery of proven therapeutic antibodies as well as novel antibodies to targets that have been previously inaccessible to therapies delivered by injection.

Safety, pharmacokinetics and pharmacodynamics of TAK-418, a novel inhibitor of the epigenetic modulator lysine-specific demethylase 1A.

AIMS: Dysregulation of histone methylation epigenetic marks may result in intellectual and developmental disability, as seen in Kabuki syndrome. Animal data suggest that increasing histone methylation by inhibiting lysine-specific demethylase 1A (LSD1) may improve cognitive outcomes in a model of Kabuki syndrome. TAK-418 is a novel LSD1 inhibitor, developed as a potential therapeutic agent for central nervous system disorders such as Kabuki syndrome. Here, we report safety, tolerability, pharmacokinetic and pharmacodynamic profiles of single and multiple doses of TAK-418 (ClinicalTrials.gov: NCT03228433, NCT03501069). METHODS: Two randomized, double-blind, placebo-controlled, phase 1 studies of oral TAK-418 were performed, a first-in-human single-rising-dose (SRD) study (5-60 mg) in healthy adult male and female volunteers (placebo, n = 10; TAK-418, n = 30), and an SRD (120-160 mg) and multiple-rising-dose (MRD) study (20-160 mg once daily for 10 days) in healthy female volunteers (placebo, n = 2 [SRD] and n = 6 [MRD]; TAK-418, n = 6 [SRD] and n = 18 [MRD]). RESULTS: TAK-418 was well tolerated. No clinically significant changes in laboratory test results or vital signs were observed and no serious adverse events were reported. TAK-418 had a nearly linear pharmacokinetic profile, with rapid absorption and short terminal half-life across the evaluated dose range. No obvious accumulation was observed after daily administration for 10 days. Administration with food delayed peak plasma concentrations but overall exposure was unaffected. TAK-418 rapidly crossed the blood-brain barrier and generally showed a dose-dependent response in the peripheral pharmacodynamic biomarker formyl-flavin adenine dinucleotide. CONCLUSION: The brain-penetrant LSD1 inhibitor TAK-418 was well tolerated, with pharmacokinetic and pharmacodynamic effects that support further investigation.

Caregiver-reported clinical characteristics and the burden associated with Kabuki syndrome.

Kabuki syndrome is a genetic disorder that can affect multiple body systems and manifest as congenital abnormalities and both developmental and socio-emotional delays. The condition is largely unknown by most primary care physicians and has no available treatment other than symptomatic management. This research sought to obtain caregiver-reported data about the experience of living with and caring for someone with Kabuki syndrome to fill a gap in the available literature. Fifty-seven caregivers participated in an online survey and reported that Kabuki syndrome affected their children in a wide variety of ways, including a high frequency of visits to various healthcare professionals. Caregivers reported their child experienced problems with hearing, eating, eyes, mouth, immune system, anxiety, depression, autism, teeth, joints, seizures, kidneys, and heart. Caregivers also described the challenges of caring for someone with Kabuki syndrome, including an impact on emotional well-being and the ability to work outside the home. This unique research characterizes the caregiver experience of living with and caring for someone with Kabuki syndrome, both through observed manifestations of Kabuki syndrome in their own children and their experience managing their treatment. Additional research is needed to investigate the patient experience of living with Kabuki syndrome.

Serum and colostral antibody production in cows immunized with recombinant human tumor necrosis factor.

The use of hyper-immune bovine colostrum as a human therapeutic platform is an emerging technology with potential to deliver the efficacy of antibody therapeutics with the convenience and safety of oral or topical application. It is necessary to understand how the bovine immune system responds to immunization with foreign proteins, both in terms of the serum antibody response and the transfer of antigen-specific antibodies into the colostrum to enable efficient large-scale production of therapeutic antibodies. We have immunized 25 cows with recombinant human tumor necrosis factor (rhTNF) and measured the levels of rhTNF-specific antibodies in the serum and colostrum of these animals. We observed a decline of 84±9% in serum IgG1 concentrations in the final weeks of pregnancy that presumably reflects rapid transport of IgG1 into colostrum. The serum IgG2 levels remained constant, such that the serum IgG1 to IgG2 ratio was 1:20 at parturition. We observed substantial animal-to-animal variability in the levels of anti-rhTNF antibodies in both serum and colostrum samples. In particular, a subset of 4 cows had extraordinarily high colostral anti-rhTNF antibody production. Only a weak correlation was found between the peak serum anti-rhTNF activity and the colostral anti-rhTNF activity in these animals. The 4 cows with high colostral anti-rhTNF activities trended toward higher serum IgG1 loss relative to average colostral anti-rhTNF producers, but this difference was not statistically significant in this small sample. The high-anti-rhTNF-producing cows also exhibited a greater proportion of rhTNF-specific antibodies that bound to bovine IgG1- and IgG2-specific detection antibodies relative to the total anti-rhTNF immunoglobulin population. This finding suggests that the isotype distribution of the anti-rhTNF response is varied between individuals and genetic or environmental factors may increase the yield of antigen-specific colostral antibodies.

A Qualitative Study to Characterize the Humanistic Burden of Kabuki Syndrome in the United States and Canada.

INTRODUCTION: Kabuki syndrome is a rare congenital condition characterized clinically by unique facial features, abnormalities in the skeleton, finger pad abnormalities, and developmental delays, as well as a range of other health issues. Existing research lacks information on the daily burden of living with Kabuki syndrome. METHODS: A survey collected caregiver- and patient-reported data about the experience of living with Kabuki syndrome in order to better understand its presentation and effect on patients and their psychosocial well-being. RESULTS: A total of 68 participants (n = 57 caregivers and n = 11 adolescents) were recruited from the USA and Canada. Caregiver survey participants reported developmental delays and lower IQ in individuals with Kabuki syndrome compared to the general population, as well as difficulty with cognitive-related tasks, need for educational accommodations, and difficulty with particular school subjects and with daily tasks. Additionally, participants reported significant emotional, social, and communication-related impacts of Kabuki syndrome. Adolescent data largely corroborated the information collected from caregivers, with the exception of adolescents reporting the emotional and social impacts as occurring less frequently. CONCLUSIONS: Kabuki syndrome is a multidimensional disease which has substantial negative effects on physical, mental, emotional, and social aspects of health-related quality of life. This research adds to the limited existing body of literature on the clinical presentation of Kabuki syndrome and provides a novel perspective into the caregiver and adolescent perception of the burden of Kabuki syndrome.

From Genotype to Phenotype-A Review of Kabuki Syndrome.

Kabuki syndrome (KS) is a rare neuro-developmental disorder caused by variants in genes of histone modification, including KMT2D and KDM6A. This review assesses our current understanding of KS, which was originally named Niikawa-Kuroki syndrome, and aims to guide surveillance and medical care of affected individuals as well as identify gaps in knowledge and unmet patient needs. Ovid MEDLINE and EMBASE databases were searched from 1981 to 2021 to identify reports related to genotype and systems-based phenotype characterization of KS. A total of 2418 articles were retrieved, and 152 were included in this review, representing a total of 1369 individuals with KS. Genotype, phenotype, and the developmental and behavioral profile of KS are reviewed. There is a continuous clinical phenotype spectrum associated with KS with notable variability between affected individuals and an emerging genotype-phenotype correlation. The observed clinical variability may be attributable to differences in genotypes and/or unknown genetic and epigenetic factors. Clinical management is symptom oriented, fragmented, and lacks established clinical care standards. Additional research should focus on enhancing understanding of the burden of illness, the impact on quality of life, the adult phenotype, life expectancy and development of standard-of-care guidelines.

AVX-470, an Orally Delivered Anti-Tumour Necrosis Factor Antibody for Treatment of Active Ulcerative Colitis: Results of a First-in-Human Trial.

BACKGROUND AND AIMS: AVX-470 is an oral, polyclonal bovine-derived anti-tumour necrosis factor (TNF) antibody in development for treatment of inflammatory bowel disease (IBD). AVX-470 neutralizes TNF locally in the gastrointestinal tract, minimizing systemic exposure. This was a double-blind, placebo-controlled, first-in-human trial designed to assess the safety, pharmacokinetics, immunogenicity and preliminary efficacy of 4 weeks of AVX-470 in patients with active ulcerative colitis (UC). METHODS: Thirty-seven patients with active UC were randomized and 36 received AVX-470 (0.2, 1.6 or 3.5g/day) or placebo over 4 weeks. Endoscopic activity was assessed by colonoscopy pre- and post-treatment. The primary endpoint was safety. Secondary endpoints included pharmacokinetics and immunogenicity. Clinical and endoscopic response and remission were assessed as exploratory endpoints. RESULTS: Thirty-three (92%) patients completed treatment and follow-up. The incidence of adverse events was similar across treatment groups and no allergic reactions or opportunistic infections were reported. AVX-470 therapy did not induce human anti-bovine antibodies (HABA). Bovine immunoglobulin (Ig) with TNF binding capacity was detected in stool, while bovine Ig levels in serum were low. Across all AVX-470 doses, 25.9% of patients achieved clinical response compared with 11.1% on placebo, with greatest improvements in the 3.5g/day group associated with proximal colon endoscopic improvement and reductions in serum CRP and IL-6. CONCLUSIONS: AVX-470 was safe and well tolerated in this first-in-human trial in UC, with efficacy trends for clinical, endoscopic and biomarker endpoints in the highest dose group (3.5g/day). Results suggest benefit of an orally delivered locally active agent in moderate to severe UC. CLINICAL TRIAL REGISTRATION NUMBER: This trial was registered with Clinicaltrials.gov as study NCT01759056 and with EudraCT as study 2012-004859-27.

Effects of AVX-470, an Oral, Locally Acting Anti-Tumour Necrosis Factor Antibody, on Tissue Biomarkers in Patients with Active Ulcerative Colitis.

BACKGROUND AND AIMS: AVX-470 is an orally administered, bovine-derived, anti-tumour necrosis factor (TNF) antibody with local activity in the gastrointestinal tract. In the first-in-human clinical trial of AVX-470 in active ulcerative colitis, we evaluated inflammatory biomarkers in colon tissue as measures of disease activity and early response to treatment. METHODS: Thirty-six patients received active drug (AVX-470 at 0.2, 1.6 or 3.5g/day) or placebo over 4 weeks. Colon biopsy samples were collected from 5 regions of colon at baseline and week 4. Tissue inflammatory biomarkers were evaluated by immunohistochemistry and quantitative reverse transcription-polymerase chain reaction (qRT-PCR), epithelial cell apoptosis by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) and bovine immunoglobulin by immunohistochemistry and mass spectrometry. Endoscopic activity (Ulcerative Colitis Endoscopic Index of Severity [UCEIS]) at colonoscopy was assessed in each colonic region by a central reader. RESULTS: Bovine immunoglobulin was observed in mucosal tissue before and after dosing in lamina propria and submucosal layers of biopsy tissue. Baseline levels of TNF, myeloperoxidase (MPO), CD68 and interleukin (IL)-1ß and, to a lesser extent, IL-6 mRNA were 2- to 3-fold higher in distal vs proximal colon tissue, corresponding to the 2- to 3-fold differences in baseline severities of endoscopic scores. Reductions of >10-fold in TNF and, to lesser extents, in MPO and epithelial cell apoptosis were observed in proximal and distal colon biopsies after 4 weeks of AVX-470 3.5g/day treatment. Reductions in TNF scores were correlated with changes in MPO and CD3 immunohistochemistry scores. CONCLUSIONS: These results are consistent with anti-TNF activity of orally administered AVX-470 in colon mucosal tissue in ulcerative colitis patients and demonstrate the utility of tissue biomarkers in assessing disease and treatment response in early clinical studies. CLINICAL TRIAL REGISTRATION NUMBER: This trial was registered with Clinicaltrials.gov as study NCT01759056 and with EudraCT as study 2012-004859-27.

RO-10-5824 is a selective dopamine D4 receptor agonist that increases novel object exploration in C57 mice.

Novelty seeking as a behavioral phenomenon emerges as a compromise between approach and avoidance behavior. Although novelty seeking is thought to play a role in drug abuse and in cognition, the biological basis for this construct is poorly understood. At a genetic level, dopamine D4 receptors (D4R) appear to be critical for the behavioral expression of novelty seeking. In humans, polymorphisms of D4R have been associated with novelty-seeking traits in general and attention deficit-hyperactivity disorder in particular. Similarly, D4R (-/-) mice exhibit less novel object exploration than D4R (+/+) mice. Due to of the paucity of selective D4R ligands for use in behavioral pharmacology studies, few studies have examined the behavioral effects of D4R compounds in animals. The present experiments characterized RO-10-5824, a new, selective D4R partial agonist with minimal affinity for dopamine D2 and D3 receptors, and tested the hypothesis that activation of D4R increases the investigation by mice of a novel object placed in the center of a familiar open field. C57BL/6J and DBA/1J male mice were used in a dose response study of the selective D4R partial agonist RO-10-5824 (0, 1.0, 3.0, or 10.0 mg/kg). While having no effect on the amount of locomotor activity in novel or familiar environments, RO-10-5824 (10.0 mg/kg) increased time spent in the center of the enclosure in the presence of a novel object in C57 but not DBA mice. These results support the hypothesis that stimulation of D4R can enhance novelty seeking in mice and that this effect may be dependent on subtle genetic differences.

Clinical outcomes and graft characteristics in pediatric matched sibling donor transplants using granulocyte colony-stimulating factor-primed bone marrow and steady-state bone marrow.

Matched sibling donor (MSD) transplant is a life-saving procedure for children with various hematological malignancies and non-malignancies. Traditionally, steady-state bone marrow (S-BM) has been used as the source of stem cells. More recently, peripheral blood stem cell (PBSC) after granulocyte-colony stimulating factor (G-CSF) mobilization has gained popularity. Adult studies of G-CSF-primed BM (G-BM) have shown that it produces rapid white blood cell engraftment like PBSC, but with less chronic graft-vs.-host disease. No such study has been published in pediatric patients. We conducted a pilot clinical trial of G-BM for pediatric patients. Ten patients were enrolled and were compared to a contemporaneous group of 12 patients who received S-BM. Patients in the G-BM group received a higher dose of total nucleated cells/kg (7.01 vs. 3.76 x 10(8), p = 0.0009), higher granulocyte-macrophage colony-forming units (CFU-GM)/kg (7.19 vs. 3.53 x 10(5), p = 0.01) and had shorter inpatient length of stay (28 vs. 40 days, p = 0.04). The engraftment, transfusion requirement and disease-free survival between the two groups were similar. We concluded that G-BM should be considered as an alternative graft source to S-BM, with the benefits of larger graft cell dose, higher CFU-GM dose and shorter length of stay.

An immobilized metal ion affinity adsorption and scintillation proximity assay for receptor-stimulated phosphoinositide hydrolysis.

A novel approach to measuring receptor-stimulated phosphoinositide hydrolysis was developed based on the principles of immobilized metal ion affinity chromatography (IMAC) and scintillation proximity assay (SPA). Hard Lewis metal ions, such as Zr(4+), Ga(3+), Al(3+), Fe(3+), Lu(3+), and Sc(3+), were immobilized on SPA beads via metal chelate and utilized as affinity ligands to entrap inositol phosphates. [3H]Inositol phosphates bound to IMAC-SPA beads through the strong interaction of their phosphate group with the immobilized metal ions. The binding brought [3H]inositol phosphates in close proximity to the scintillant embedded in the SPA beads, thereby allowing the radioactivity to be quantified. Quantification of [3H]inositol phosphate production in cells preincubated with [3H]inositol provided a highly sensitive measurement of phosphoinositide hydrolysis. The utility of this approach was demonstrated in measuring the response mediated by the G-protein-coupled neurokinin NK1 receptor and the tyrosine kinase-linked platelet-derived growth factor (PDGF) receptor. Substance P stimulated phosphoinositide hydrolysis concentration-dependently in CHO cells expressing NK1 receptors with a maximal 12-fold increase in inositol phosphate production. Similarly, PDGF-BB stimulated a 5-fold increase in phosphoinositide hydrolysis in quiescent Swiss 3T3 cells. This new approach is highly sensitive, fast, simple, easily performed on 96-well plates, and amenable for high-throughput screening.