Increasing Dose Levels Research Articles

Effect of increasing dose level of a novel consensus bacterial 6-phytase variant on phytate degradation in broilers fed diets containing varied phytate levels

ABSTRACT 1. The effect of increasing the dose level of a novel consensus bacterial 6-phytase variant on apparent ileal digestibility (AID) of phosphorus (P), phytic acid (inositol hexa-phosphate, IP6) and ileal IP6 degradation profile was studied in diets containing varying phytate-P (PP) levels. 2. Ross 308, one-day-old males (n = 1,800) were allocated to cages (20 birds/cage, six cages/treatment) in a completely randomised design employing a 3 × 5 factorial arrangement (three PP levels: 2.45 (low) 2.95 (medium) and 3.45 g/kg (high); five dose levels of phytase (PhyG): 0, 500, 1,000, 2,000 and 4,000 FTU/kg). Phased diets were based on wheat, corn, soybean meal, rapeseed meal and rice bran (d 0 to 10; 2.60 g/kg digestible P, 7.6 g/kg calcium (Ca); d 11 to 21; 2.10 g/kg digestible P, 6.4 g/kg Ca). Ileal digesta was collected on d 21 for determination of P, IP6 and IP-esters content. Data were analysed by factorial ANOVA; means separation was achieved using Tukey’s HSD test. 3. Increasing PP reduced AID of IP6 and sum of IP3-6 (%) (P < 0.05) but absolute P-release (g/kg diet) above NC was increased (P < 0.05) at high vs. low PP. Increasing phytase dose exponentially increased (P < 0.001) AID IP6, sum of IP3-6 (%) and digestible IP3-6-P g/kg diet (P < 0.001). AID P was increased but there was an interaction with PP level (P < 0.001). Ileal accumulation of IP5-3-P was universally low with PhyG at ≥1,000 FTU/kg (<0.06 g/100 g DM). At 2,000 and 4,000 FTU/kg, AID IP6 was 97.2, 92.7, 92.6% and 100, 97.2, 97.1%, respectively, at low, medium and high PP. At 2,000 FTU/kg, phytate-P release estimated as the increase (above NC) in ileal digestible sum of IP3-6-P in the diet was 2.26, 2.59 and 3.10 g/kg in low, medium and high PP, respectively. 4. The data demonstrated that the novel phytase was effective in breaking down phytate to low IP-esters in diets with varied PP content but the optimal dose level for maximising P-release may differ in diets with varying PP content.

Virtual monoenergetic images from dual-energy CT: systematic assessment of task-based image quality performance.

To compare task-based image quality (TB-IQ) among virtual monoenergetic images (VMI) and linear-blended images (LBI) from dual-energy CT as a function of contrast task, radiation dose, size, and lesion diameter. A TB-IQ phantom (Mercury Phantom 4.0, Sun Nuclear Corporation) was imaged on a third-generation dual-source dual-energy CT with 100/Sn150 kVp at three volume CT dose levels (5, 10, 15 mGy). Three size sections (diameters 16, 26, 36 cm) with subsections for image noise and spatial resolution analysis were used. High-contrast tasks (e.g., calcium-containing stone and vascular lesion) were emulated using bone and iodine inserts. A low-contrast task (e.g., low-contrast lesion or hematoma) was emulated using a polystyrene insert. VMI at 40-190 keV and LBI were reconstructed. Noise power spectrum (NPS) determined the noise magnitude and texture. Spatial resolution was assessed using the task-transfer function (TTF) of the three inserts. The detectability index (d') served as TB-IQ metric. Noise magnitude increased with increasing phantom size, decreasing dose, and decreasing VMI-energy. Overall, noise magnitude was higher for VMI at 40-60 keV compared to LBI (range of noise increase, 3-124%). Blotchier noise texture was found for low and high VMIs (40-60 keV, 130-190 keV) compared to LBI. No difference in spatial resolution was observed for high contrast tasks. d' increased with increasing dose level or lesion diameter and decreasing size. For high-contrast tasks, d' was higher at 40-80 keV and lower at high VMIs. For the low-contrast task, d' was higher for VMI at 70-90 keV and lower at 40-60 keV. Task-based image quality differed among VMI-energy and LBI dependent on the contrast task, dose level, phantom size, and lesion diameter. Image quality could be optimized by tailoring VMI-energy to the contrast task. Considering the clinical relevance of iodine, VMIs at 50-60 keV could be proposed as an alternative to LBI.

A Phase I Study of RO7297089, a B-Cell Maturation Antigen (BCMA)-CD16a Bispecific Antibody in Patients with Relapsed/Refractory Multiple Myeloma (RRMM)

A Phase I Study of RO7297089, a B-Cell Maturation Antigen (BCMA)-CD16a Bispecific Antibody in Patients with Relapsed/Refractory Multiple Myeloma (RRMM)

Phase 1/2 Study of Oral TP-0184 for the Treatment of Anemia in Adults with Low- or Intermediate-Risk Myelodysplastic Syndromes

Patients with anemia due to lower-risk myelodysplastic syndromes (MDS) have limited treatment options. The transforming growth factor β (TGF-β) pathway has been implicated in contributing to ineffective hematopoiesis in patients with MDS. Members of the TGF-β superfamily include activin receptor-like kinase 2 (ALK2) and ALK5. ALK2 signaling plays a key role in modulating hepcidin, an important regulator of iron homeostasis (and thus erythropoiesis). Increased levels of hepcidin have been linked to anemia in patients with chronic inflammation and cancer, including multiple myeloma (Maes K, et al. Blood. 2010;116:3635-44). The role of hepcidin in MDS-related anemia is unknown and needs to be explored. ALK5 signaling through SMAD2/3 phosphorylation is constitutively active in bone marrow precursor cells from patients with MDS (Zhou L, et al. Blood. 2008;112:3434-43). Inhibition of ALK5 suppresses phosphorylation of SMAD2 in MDS hematopoietic progenitor cells and stimulates hematopoiesis in cells derived from patients with MDS. Collectively, these data suggest that blockade of the TGF-β-SMAD2/3 signaling pathway with an ALK5 inhibitor has the potential to benefit patients with anemia due to MDS.TP-0184 is a small-molecule, dual inhibitor of ALK2 and ALK5. In vitro, TP-0184 inhibits downstream signaling from ALK2 by reducing the phosphorylation of SMAD1/5/8 and blocks hepcidin expression (Peterson PW, et al. Blood. 2017;130 [suppl_1]: 937). Ex vivo, TP-0184 inhibits downstream signaling from ALK5 by reducing SMAD2/3 phosphorylation (data on file). By inhibiting both the ALK2 and ALK5 signaling pathways, TP-0184 may reduce ineffective erythropoiesis in patients with MDS.An open-label, single-arm, phase 1/2 study (NCT04623996) is being undertaken to evaluate the preliminary safety and efficacy of TP-0184 in treating anemia in adults (aged ≥18 years) with MDS. To be eligible, patients must have low- or intermediate-risk MDS (de novo or secondary) per the Revised International Prognostic Scoring System and have relapsed, exhibited an inadequate response to, or been refractory, resistant, or intolerant to treatment with an erythropoiesis-stimulating agent. Patients may have low or high red blood cell transfusion burden, must exhibit adequate major organ function, and must have an Eastern Cooperative Oncology Group performance status of 0-2. Key exclusion criteria include the presence of concomitant severe cardiovascular disease, such as congestive heart failure, myocardial infarction, angina, and/or uncontrolled cardiac arrhythmia; history of stroke, deep venous thrombosis, or pulmonary or arterial embolism; presence of clinically significant anemia due to iron, vitamin B12, or folate deficiencies, autoimmune or hereditary hemolytic anemia, or gastrointestinal bleeding; and prior allogeneic or autologous stem cell transplant.In this study, TP-0184 will be administered orally once daily for 24 weeks. The primary and secondary endpoints of each study phase are summarized in the table. Recruitment is ongoing, with approximately 30 patients targeted for enrollment in phase 1 and 10-60 patients targeted for enrollment in phase 2. In phase 1, increasing dose levels of TP-0184 ranging from 20 to 270 mg will be evaluated, with 1-6 patients dosed at each level. Dose escalation will be performed using a two-parameter Bayesian logistic regression model. Determination of the recommended phase 2 dose (RP2D) will be informed by the maximum tolerated or maximum administered dose in phase 1. In phase 2, the efficacy of TP-0184 at the RP2D will be monitored using Bayesian posterior probability to optimize enrollment with Bayesian stopping rules. Bayesian monitoring of responses will be started after the first 10 enrolled patients are evaluable for efficacy. [Display omitted] DisclosuresVerma: Medpacto: Research Funding; Curis: Research Funding; Eli Lilly: Research Funding; Stelexis: Consultancy, Current equity holder in publicly-traded company; Novartis: Consultancy; Acceleron: Consultancy; Celgene: Consultancy; Stelexis: Current equity holder in publicly-traded company; Throws Exception: Current equity holder in publicly-traded company; Incyte: Research Funding; GSK: Research Funding; BMS: Research Funding. Brunner: Celgene, Forty Seven Inc, Jazz: Other: Advisory Board; Novartis, Celgene, Takeda, AstraZeneca: Research Funding. Pennock: Sumitomo Dainippon Pharma Oncology, Inc: Current Employment. McMullen: Sumitomo Dainippon Pharma Oncology, Inc: Current Employment. Wade: Sumitomo Dainippon Pharma Oncology, Inc: Current Employment. Yang: Sumitomo Dainippon Pharma Oncology, Inc: Current Employment. Xie: Sumitomo Dainippon Pharma Oncology, Inc: Current Employment. Whatcott: Sumitomo Dainippon Pharma Oncology, Inc: Current Employment. Foulks: Sumitomo Dainippon Pharma Oncology, Inc: Current Employment. Melear: Janssen: Speakers Bureau; Astrazeneca: Speakers Bureau; TG Therapeutics: Speakers Bureau.

Physiologically based kinetic modelling predicts the in vivo relative potency of riddelliine N-oxide compared to riddelliine in rat to be dose dependent

Pyrrolizidine alkaloids (PAs) are toxic plant constituents occurring often in their N-oxide form. This raises the question on the relative potency (REP) values of PA-N-oxides compared to the corresponding parent PAs. The present study aims to quantify the in vivo REP value of riddelliine N-oxide compared to riddelliine using physiologically based kinetic (PBK) modelling, taking into account that the toxicity of riddelliine N-oxide depends on its conversion to riddelliine by intestinal microbiota and in the liver. The models predicted a lower Cmax and higher Tmax for the blood concentration of riddelliine upon oral administration of riddelliine N-oxide compared to the Cmax and Tmax predicted for an equimolar oral dose of riddelliine. Comparison of the area under the riddelliine concentration–time curve (AUCRID) obtained upon dosing either the N-oxide or riddelliine itself revealed a ratio of 0.67, which reflects the in vivo REP for riddelliine N-oxide compared to riddelliine, and appeared to closely match the REP value derived from available in vivo data. The models also predicted that the REP value will decrease with increasing dose level, because of saturation of riddelliine N-oxide reduction by the intestinal microbiota and of riddelliine clearance by the liver. It is concluded that PBK modeling provides a way to define in vivo REP values of PA-N-oxides as compared to their parent PAs, without a need for animal experiments.

Abstract MP22: Effect Of Nanoparticle Size And Dose On Detection Of Aortic Injury Using Nanoparticle Contrast-enhanced Computed Tomography

Background: Early detection and prediction of disease progression are critical for improving outcomes in patients with aortic aneurysms and dissections (AAD). Recently, we reported that nanoparticle contrast-enhanced computed tomography (n-CECT) enables early detection of aortic injury before vessel enlargement is evident on CT angiography. In this work, we investigated the effect of nanoparticle contrast agent (NPCA) size and dose on detection of aortic injury. Additionally, we performed a longitudinal study to examine long-term fate of intramural NPCA. Methods: In a mouse model of sporadic AAD, mice (n=8/group) were challenged with high fat diet for 5 weeks and angiotensin-II infusion during the last week. Animals were intravenously administered one of three NPCA size variants (80, 150 and 250 nm). For dose effect study, 150 nm NPCA variant was tested at 3 dose levels: 300, 600 and 1200 mg I/kg. In vivo n-CECT was performed after 4 days. Ex vivo n-CECT and gross examination were performed on excised aortas. To study intramural fate of NPCA, a subset of animals underwent longitudinal CT imaging for up to 6 months. Results: All NPCA size variants showed a higher incidence of n-CECT findings compared to gross aortic examination: absolute improvements in detection rates were 12% for 80 nm , 28% for 150 nm , and 8% for 250 nm . NPCA dose analysis showed that sensitivity of n-CECT for detection of aortic injury improved with increasing dose level (33% for 300 mg I/kg , 44% for 600 mg/kg , and 62% for 1200 mg I/kg ) (Figure 1). Longitudinal imaging demonstrated clearance of a majority of intramural NPCA that accumulated at sites of aortic pathology by 4 months. Furthermore, n-CECT imaging enabled monitoring of vascular permeability changes at sites of aortic injury. Conclusion: Regardless of NPCA size, n-CECT imaging showed higher sensitivity for early detection of aortic degeneration compared to gross aortic examination. Detection of aortic injury improved with increasing NPCA dose.

Multiarmed Bandit Designs for Phase I Dose-Finding Clinical Trials With Multiple Toxicity Types

The goal of a phase I dose-finding trial is to determine the dose level of a new drug with acceptable toxicity. The optimal dose level is determined by sequentially allocating patients to increasing dose levels while monitoring any safety concerns. In practice, multiple toxicity types may be of interest and with varying degrees of importance of each toxicity type. To address this, scoring systems have been developed and conventional adaptive designs, such as the continual reassessment method (CRM), have accordingly been modified to handle them. In this article, we consider how to model the dose-finding problem under the multiarmed bandit framework, which naturally embeds the tradeoff between exploring the toxicity of dose levels and exploiting the current information to optimize benefit. We then propose a Bayesian multiarmed bandit design, dubbed quasi-likelihood optimistic bandit (QLOB), which has desirable operating characteristics, including allocation of patients to the dose level which has an estimated toxicity score closest to the target level and is relatively less explored. In extensive simulation studies, it is demonstrated that QLOB outperformed toxicity-score-based designs, such as quasi-CRM (QCRM), and general Bayesian optimal interval (gBOIN) in most scenarios considered; and performed much better than the conventional CRM and “3 + 3” designs with respect to dose recommendation and patient allocation. In addition, our design is shown to be robust against misspecification of the relevant hyper-parameter, and to have improved performance as the number of enrolled patients increases.

Combination of Olaparib with radiotherapy for triple‐negative breast cancers: One‐year toxicity report of the RADIOPARP Phase I trial

Triple-negative breast cancer (TNBC) cells are sensitive to PARP1 inhibitors in vitro. The combination of Olaparib and radiotherapy for TNBC is currently evaluated in the Phase I RADIOPARP trial. RADIOPARP is a monocentric prospective open-label Phase I dose-escalation trial evaluating the combination of breast radiotherapy and Olaparib in TNBC patients with inflammatory, locoregionally advanced or metastatic disease, or with residual disease after neoadjuvant chemotherapy. Olaparib was orally given at increasing dose levels (50, 100, 150 or 200 mg twice a day [BID]); radiotherapy consisted of 50 Gy to the breast or chest wall with or without lymph node irradiation. Twenty-four TNBC patients were enrolled between September 2017 and November 2019. Olaparib was escalated to 200 mg BID without dose-limiting toxicities. At 1-year follow-up, no treatment-related grade ≥3 toxicity was observed. One patient (4.2%) had persistent grade 2 adverse events (breast pain, fibrosis and deformity). There was no cardiac, pulmonary or digestive toxicity related to treatment. The 1-year follow-up report of the RADIOPARP Phase I trial, evaluating Olaparib associated with breast radiotherapy in TNBC patients, consequently demonstrated an excellent toxicity profile of this combination with few low-grade adverse events.

A Bayesian Approach to Successive Comparisons

The present article discusses and compares multiple testing procedures (MTPs) for controlling the family wise error rate. Machekano and Hubbard (2006) have proposed empirical Bayes approach that is a resampling based multiple testing procedure asymptotically controlling the familywise error rate. In this paper we provide some additional work on their procedure, and we develop resampling based step-down procedure asymptotically controlling the familywise error rate for testing the families of one-sided hypotheses. We apply these procedures for making successive comparisons between the treatment effects under a simple-order assumption. For example, the treatment means may be a sequences of increasing dose levels of a drug. Using simulations, we demonstrate that the proposed step-down procedure is less conservative than the Machekano and Hubbard’s procedure. The application of the procedure is illustrated with an example.

IMGN779, a Next-Generation CD33-Targeting Antibody-Drug Conjugate (ADC) Demonstrates Initial Antileukemia Activity in Patients with Relapsed or Refractory Acute Myeloid Leukemia

IMGN779, a Next-Generation CD33-Targeting Antibody-Drug Conjugate (ADC) Demonstrates Initial Antileukemia Activity in Patients with Relapsed or Refractory Acute Myeloid Leukemia

A Single Direct Intratumoral Injection of TTI-621 (SIRPαFc) Induces Antitumor Activity in Patients with Relapsed/Refractory Mycosis Fungoides and Sézary Syndrome: Preliminary Findings Employing an Immune Checkpoint Inhibitor Blocking the CD47 “Do Not Eat” Signal

BackgroundCD47 is an immune checkpoint that binds to signal regulatory protein alpha (SIRPα) and delivers a “do not eat” signal to suppress macrophage phagocytosis. Tumor cells frequently overexpress CD47 to evade macrophage-mediated destruction. TTI-621 (SIRPαFc) is an immune checkpoint inhibitor consisting of the CD47 binding domain of human SIRPα linked to the Fc region of human IgG1 designed to both: 1) block the CD47 “do not eat” signal, and 2) engage macrophage Fcγ receptors with IgG1 Fc to enhance phagocytosis and antitumor activity. It is hypothesized that direct intratumoral injection of TTI-621 may enhance both local and systemic antitumor activity.MethodsA Phase 1, multicenter, open-label study is ongoing to characterize the safety and tolerability of intratumoral injection of TTI-621 (NCT02890368). Eligible patients (pts) are adults with relapsed or refractory mycosis fungoides/Sézary syndrome or percutaneously-accessible solid tumors who have progressed on standard anticancer therapy or for whom no other approved therapy exists. Pts are enrolled in sequential cohorts to receive a single intratumoral injection of TTI-621 at increasing dose levels to characterize safety, pharmacokinetics, pharmacodynamics, and preliminary evidence of antitumor activity. Repeat TTI-621 intratumoral dosing has recently been initiated. Serial, post-injection biopsies are collected to assess the temporal impact of TTI-621 on the tumor microenvironment.ResultsNine pts (6 M/3F, age 57-85 years) have been enrolled as of July 2017. Diagnoses include mycosis fungoides/Sézary syndrome (N=6), melanoma (N=1), leiomyosarcoma (N=1), and squamous cell carcinoma (N=1). A single intratumoral injection of 1 mg, 3 mg, or 10 mg TTI-621 has been well tolerated by all enrolled pts. The most frequently reported adverse events were fatigue in 5 pts, chills in 4 pts, and decreased appetite in 3 pts. All treatment-related AEs were Grade 1 or 2 in severity. No dose limiting toxicity has been observed to date. All 6 pts with mycosis fungoides/Sézary syndrome experienced decreases in tumor size and/or decreased circulating Sézary cells (3 of 3 pts) as determined by a decrease in a peripheral clonal T-cell populationor CD4:CD8 ratio after a single intratumoral injection of TTI-621. Responses ranged from loco-regional to systemic effects. One pt with localized refractory mycosis fungoides on the dorsum of the foot obtained a complete response of the injected lesion that is ongoing after 17+ weeks of follow up. NanoString analysis of peripheral blood and tumor tissue pre- and post-intratumoral injection of TTI-621 indicated alterations in genes associated with activation of the innate immune system and upregulation of IFN-associated genes.ConclusionsThese preliminary Phase 1 data suggest that mycosis fungoides and its leukemic variant, Sézary syndrome, are highly responsive to a single dose of TTI-621 delivered by intratumoral injection. One pt achieved a complete response of the injected lesion and 5 additional pts experienced decreases in tumor size and/or decreased circulating Sézary cells. Intratumoral injections were well tolerated by all pts. Evidence of innate immune activation was documented, consistent with the proposed function of TTI-621 as an innate immune checkpoint inhibitor. DisclosuresQuerfeld:Soligenix: Research Funding; Elorac: Research Funding; Celgene: Honoraria, Research Funding; MiRagen: Honoraria, Research Funding; Actelion: Honoraria, Research Funding; Medivir: Honoraria; Mallinckrodt: Honoraria; Mindera: Consultancy; Kyowa: Research Funding; Trillium Therapeutics: Research Funding; City of Hope: Employment. Thompson:Trillium Therapeutics: Research Funding. Taylor:Blue Print Medicines: Consultancy, Honoraria; Eisai Inc.: Consultancy, Honoraria, Speakers Bureau; Bristol Myers Squibb: Consultancy, Honoraria, Speakers Bureau; Trillium Therapeutics: Consultancy, Honoraria. Pillai:Trillium Therapeutics: Research Funding. Johnson:Trillium Therapeutics: Employment. Catalano:Trillium Therapeutics: Employment; Apotex Inc.: Employment. Petrova:Trillium Therapeutics: Employment, Equity Ownership. Uger:Trillium Therapeutics: Employment, Equity Ownership, Patents & Royalties. Irwin:Hoffmann La Roche: Employment, Equity Ownership; Trillium Therapeutics: Employment, Equity Ownership. Sievers:Trillium Therapeutics: Employment, Equity Ownership. Akilov:Seattle Genetics: Consultancy; Medivir: Consultancy; Actelion Pharmacuticals: Consultancy, Research Funding; Trillium Therapeutics: Research Funding.

Phase 1 study of CB-103, a novel first-in-class inhibitor of the CSL-NICD gene transcription factor complex in human cancers.

3020 Background: CB-103 selectively inhibits the CSL-NICD interaction leading to down-regulation of CSL-NICD mediated oncogenic pathway activation downstream of NOTCH receptor/ligand signaling, and has shown potent anti-cancer activity as single agent and in combination with targeted/chemotherapies in preclinical models. The aim of this dose escalation/expansion phase 1/2a study is to assess safety, maximum tolerated dose (MTD) and recommended phase 2 dose (RP2D), preliminary activity, pharmacokinetics and pharmacodynamics of CB-103. Methods: Eligible were adult patients (pts) with advanced or recurrent selected solid tumors. Tumor tissue, where available, was retrospectively tested for NOTCH pathway activating mutations and surrogate tissues were evaluated for gene expression of related target genes. CB-103 was given orally in 28 days cycles at escalating doses until disease progression or toxicity. In a dose confirmatory cohort, NOTCH activation will be prospectively assessed to determine eligibility. Results: Forty-one pts (19 adenoid cystic carcinoma (ACC), 16 colorectal and 4 breast cancer, 2 prostate cancer) were assigned to increasing dose levels starting from 15mg once daily (OD). Median age was 55 years (range 25-76). Median number of prior lines of therapy was 2 (range 0-7). Thirty-two pts in 8 escalation groups completed the 28-day DLT window. One DLT (asymptomatic grade (G) 3 GGT increase) was observed at the highest dose (600mg). Related treatment emergent adverse events (AE) occurring in &gt;10% of pts were nausea (24%), diarrhea (20%), dyspepsia (15%), fatigue (12%) and vision blurred (12%), all G 1/2. No discontinuations occurred due to treatment-related AEs. The MTD has not been reached. Several pts reported vision changes that improved over time and were fully reversible after stopping the drug. Median time on treatment for all pts was 52 days (range 5-249). Best response was stable disease (SD). For ACC pts, preliminary median PFS was 21.7 weeks (95% confidence interval (CI) 13.7-22.4 weeks) and disease control rate (DCR) was 79% at week 8 and 58 % at week 20. Three pts with ACC harboring activating NOTCH alterations had radiologically confirmed stable disease (SD) &gt; 6 months. Importantly, in 3 pts with NOTCH positive disease a temporary stop of tumor growth was observed. One pt showed a reduction in size of a liver lesion up to 25% before progression due to new lesions. Mechanistically, strong on-treatment downregulation of NOTCH target genes was observed. The dose of 600mg CB-103 OD was declared the RP2D. Conclusions: CB-103 is the first drug to effectively control the CSL-NICD transcription complex. CB-103 is well tolerated in pts with advanced tumors and, as expected on the basis of mechanistic studies, in the absence of the typical toxicities associated with Notch targeting GSIs or mABs. The RP2D has been established for advancing clinical development into phase 2. Clinical trial information: NCT03422679.

Effects of Aleurone Supplementation on Glucose-Insulin Metabolism and Gut Microbiome in Untrained Healthy Horses.

Aleurone, a layer of the bran fraction, is deemed to be responsible for the positive health effects associated with the consumption of whole-grain products. Studies on rodents, pigs, and humans report beneficial effects of aleurone in five main areas: the reduction of oxidative stress, immunomodulatory effects, modulation of energy management, digestive health, and the storage of vitamins and minerals. Our study is the first aleurone supplementation study performed in horses. The aim of this study was to investigate the effect of an increase in the dose levels of aleurone on the postprandial glucose-insulin metabolism and the gut microbiome in untrained healthy horses. Seven adult Standardbred horses were supplemented with four different dose levels of aleurone (50, 100, 200, and 400 g/day for 1 week) by using a Latin square model with a 1-week wash out in between doses. On day 7 of each supplementation week, postprandial blood glucose-insulin was measured and fecal samples were collected. 16S ribosomal RNA (rRNA) gene sequencing was performed and QIIME2 software was used for microbiome analysis. Microbial community function was assessed by using the predictive metagenome analysis tool Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) and using the Metacyc database of metabolic pathways. The relative abundancies of a pathway were analyzed by using analysis of composition of microbiomes (ANCOM) in R. There was a significant dose-dependent increase in the postprandial time to peak of glucose (p = 0.030), a significant delay in the time to peak of insulin (p = 0.025), and a significant decrease in both the insulin peak level (p = 0.049) and insulin area under the curve (AUC) (p = 0.019) with increasing dose levels of aleurone, with a consideration of 200 g being the lowest significant dose. Alpha diversity and beta diversity of the fecal microbiome showed no significant changes. Aleurone significantly decreased the relative abundance of the genera Roseburia, Shuttleworthia, Anaerostipes, Faecalibacter, and Succinovibrionaceae. The most pronounced changes in the relative abundance at phyla level were seen in Firmicutes and Verrucomicrobia (downregulation) and Bacteroidetes and Spirochaetes (upregulation). The PICRUSt analysis shows that aleurone induces a downregulation of the degradation of L-glutamate and taurine and an upregulation of the three consecutive pathways of the phospholipid membrane synthesis of the Archaea domain. The results of this study suggest a multimodal effect of aleurone on glucose-insulin metabolism, which is most likely to be caused by its effect on feed texture and subsequent digestive processing; and a synergistic effect of individual aleurone components on the glucose-insulin metabolism and microbiome composition and function.

Influence of γ-ray exposure and dose dependent characteristics of (n)PbS–(p)Si hetero-structure

An (n)PbS–(p)Si hetero-structure was developed by preparing the lead sulfide (PbS) nanostructure thin films deposited on p-type Si wafer using the successive ionic layer adoption and reaction (SILAR) method. To investigate the radiation detection capability of (n)PbS–(p)Si hetero-structure. For this purpose, nanostructure, photoluminescence, optical bandgap and I–V characteristic have been examined with various γ-ray dose 0, 25, 50 and 75 kGy. X-ray diffraction of as deposited PbS comparing to the irradiated samples suggested that the crystalline is improved with the γ-ray up to 50 kGy dose. The morphology studies showed that the average sizes increased from 55 to 105 nm with increasing the incident γ-ray dose level and decreased with further increase of dose. Energy dispersive X-ray (EDX) analysis confirmed the elemental composition of the as deposited PbS thin films. The reflectance of the (n)PbS–(p)Si hetero-structure in the ultraviolent–visible–near infrared reflectance (UV–Vis–NIR) region reduced about 40% compared to as deposited sample. The band edge shifted to longer wavelengths with increasing dose level to 50 kGy, and the reverse trend is observed at 75 kGy dose. Photoluminescence (PL) spectra revealed that the (n)PbS–(p)Si hetero-structure received the lowest recombination rate at 50 kGy. The rectifying current–voltage (I–V) characteristics revealed impact of the γ-ray irradiation dose on the hetero-structure electrical parameters. The rectifying ratio and turn-on voltage reduced from 22.3 to 7.4 at 5 V, and 1.25–0.5 V with γ-ray irradiation, respectively. All ideality factors of as deposited and irradiated (n)PbS–(p)Si hetero-structure are greater than 4. The barrier height, series resistance exhibited minimum values (0.49 eV, 1.47 kΩ) and the largest saturation current 1.69 × 10–4 A, at 50 kGy.

Impact of dose reduction and the use of an advanced model-based iterative reconstruction algorithm on spectral performance of a dual-source CT system: A task-based image quality assessment

PurposeTo assess the impact of dose reduction and the use of an advanced modeled iterative reconstruction algorithm (ADMIRE) on image quality in low-energy monochromatic images from a dual-source dual energy computed tomography CT (DSCT) platform. Materials and methodsAcquisitions on an image-quality phantom were performed using DSCT equipment with 100/Sn150 kVp for four dose levels (CTDIvol: 20/11/8/5mGy). Raw data were reconstructed for six energy levels (40/50/60/70/80/100 keV) using filtered back projection and two levels of ADMIRE (A3/A5). Noise power spectrum (NPS) and task-based transfer function (TTF) were calculated on virtual monoenergetic images (VMIs). Detectability index (d′) was computed to model the detection task of two enhanced iodine lesions as function of keV. ResultsNoise-magnitude was significantly reduced between 40 to 70 keV by −56±0% (SD) (range: −56%–−55%) with FBP; −56±0% (SD) (−56%–−56%) with A3; and −57±1% (SD) (range: −57%–−56%) with A5. The average spatial frequency of the NPS peaked at 70 keV and decreased as ADMIRE level increased. TTF values at 50% were greatest at 40 keV and shifted towards lower frequencies as the keV increased. The detectability of both lesions increased with increasing dose level and ADMIRE level. For the simulated lesion with iodine at 2mg/mL, d’ values peaked at 70 keV for all reconstruction types, except for A3 at 20 mGy and A5 at 11 and 20 mGy, where d’ peaked at 60 keV. For the other simulated lesion, d’ values were highest at 40 keV and decreased beyond. ConclusionAt low keV on VMIs, this study confirms that iterative reconstruction reduces the noise magnitude, improves the spatial resolution and increases the detectability of enhanced iodine lesions.

Transfer of tropane alkaloids (atropine and scopolamine) into the milk of subclinically exposed dairy cows

Tropane alkaloids are toxic secondary metabolites found in agricultural weeds, like jimson weed (Datura stramonium) and henbane (Hyoscyamus niger). The intake of food and feed contaminated with tropane alkaloids led to several incidents of poisoning in humans and animals. Because data on the transfer of tropane alkaloids into the milk of exposed dairy cows were not available in scientific literature, the present study was carried out. Four cows received tropane alkaloids (atropine sulfate and scopolamine hydrobromide trihydrate) orally in three increasing dosage levels for five days each. The total doses of pharmacologically active alkaloids (sum of l-hyoscyamine and scopolamine) at the levels 1, 2, and 3 were 93, 186, and 279 μg/kg body weight/day, respectively. None of the applied dosage levels induced obvious clinical symptoms in the cows. The alkaloid content in composite milk of individual cows was measured for each milking time. Even though the maximum mean transfer rates (atropine: 0.037%, scopolamine: 0.007%) were very low, a transfer of tropane alkaloids into milk could already be proven at the lowest dosage level. At the highest dosage level, the biologically active substances were detected in milk at a mean level of 1.60 ± 0.07 μg/kg. The results obtained in this study indicate that under particular circumstances contaminated raw milk may contribute to the exposure of consumers to tropane alkaloids.

A phase I trial of chemoimmunotherapy combining bacillus Calmette-Guerin (BCG) and intravesical gemcitabine for patients with BCG-relapsing high-grade nonmuscle-invasive bladder cancer.

TPS509 Background: Intravesical BCG is the most effective treatment for high-grade non-muscle invasive bladder cancer (NMIBC), yet recurrences are common. Patients with BCG-relapsing NMIBC are often re-treated with BCG or BCG with interferon (IFN) with an expected response rate of only 40–60%. Several studies show that a major mechanism of resistance to BCG is high levels of myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs) in the pretreatment tumor microenvironment. Gemcitabine is a commonly used intravesical treatment for NMIBC that, in addition to direct anti-tumor cytotoxic effects, may also reduce MDSCs and Tregs. Prior trials combining BCG with intravesical mitomycin C have shown improved efficacy over BCG alone but with higher toxicity. While gemcitabine has been shown to be better tolerated than mitomycin as an intravesical treatment, no study has looked at combined BCG and intravesical gemcitabine. We hypothesize that combining BCG and intravesical gemcitabine will be well tolerated and result in higher response rates by reducing levels of MDSCs and Tregs. A novel aspect of our trial design is the use of a modified continual reassessment method to more accurately identify the maximum tolerated dose instead of the traditional 3 + 3 design used in most NMIBC phase I trials. Methods: This is an investigator-initiated phase I trial (NCT04179162) that will study the safety of alternating intravesical gemcitabine and BCG. Inclusion and exclusion criteria are designed so most patients who would ordinarily be re-treated with BCG or BCG/IFN would be eligible. Patients must have recurrent high-grade NMIBC within 24 months of their last BCG treatment without meeting the criteria for BCG-unresponsive NMIBC. Intravesical gemcitabine is given twice a week on weeks 1, 4, 7, and 10, for a total of 8 doses. BCG (50 mg) is given once a week on weeks 2, 3, 5, 6, 8, and 9, for a total of 6 doses. The trial is monitored using a modified continual reassessment method with increasing dose levels of gemcitabine (500 mg, 1,000 mg, 1,500 mg, and 2,000 mg) being evaluated. Adverse events are assessed using the Common Terminology Criteria for Adverse Events version 5.0. The primary objective is to determine the maximum tolerated dose of this combination to inform our planned phase II trial. Correlative studies will look at the immunomodulating effects of gemcitabine by evaluating changes in immune cell populations in serial blood and urine specimens. Tissue and urine will also be evaluated for molecular determinants of response and resistance to the combination. The trial is open to enrollment with 10 of 25 planned patients accrued to date. Clinical trial information: NCT04179162.

LOW DOSE IL-2 FOR THE TREATMENT OF MODERATE TO SEVERE ULCERATIVE COLITIS

Abstract Background A significant proportion of patients with ulcerative colitis (UC) have suboptimal responses to medical therapy. Expansion of regulatory T cells (Tregs), but not conventional T cells (Tcons), through the use of low doses (LD) of the T cell growth factor Interleukin-2 (IL-2, Proleukin®), has been a promising approach in other immune-mediated diseases and pre-clinical humanized UC mouse models. We performed a phase 1b/2a clinical trial in patients with moderate-to-severe UC to determine if subcutaneously (SC) administered LD IL-2 is safe and results in a biological response. Methods An open-label single arm phase 1b/2a trial of LD SC IL-2 in moderate-to-severe UC patients involving 2 phases: (1) dose escalation phase, in which three sequentially increasing dose levels were tested: 0.3x106 IU/m2/day (Dose A), 1x106 IU/m2/day (Dose B) or 1.5x106 IU/m2/day (Dose C); (2) treatment at the maximum tolerated dose (MTD) phase, defined as the highest tolerated dose level at which fewer than 2 evaluable subjects experienced a dose limiting toxicity (DLT). Adult patients with UC and a Mayo score of 6–12 were included and received a daily SC injection. The primary objectives were safety and determination of MTD. Clinical and laboratory assessments occurred pre-treatment and at weeks 1, 2, 4, 6, 8 and 12, with sigmoidoscopy at baseline and week 8. Peripheral Treg (pTreg) expansion was defined as &amp;gt;2X increase in % CD4+CD25+ cells. Tcon activation is measured by pSTAT5 in CD4+CD25- cells. Results 26 patients were enrolled. Baseline characteristics were similar among groups. There were no serious adverse events (AEs). Common (occuring in &amp;gt;10% of patients) AEs included injection site reactions and malaise across all doses. In the dose escalation phase, 4 patients received Dose A: pTreg expansion was noted in 2/4; 1 achieved clinical remission. 7 patients received Dose B: 1 developed a rash deemed a DLT; 2 achieved remission and 1 achieved response. pTreg expansion was noted in all patients at this dose. 5 patients received Dose C. No DLT was observed. pTreg expansion was seen in all patients in this group, but unwanted Tcon activation was also observed at this dose level. No patient achieved clinical response at this dose. Therefore, MTD was modified to maximum effective dose (MED) and Dose B was considered MED; 10 additional patients were enrolled: 2 achieved remission, 4 response, 2 had no response and 2 withdrew (headaches and worsening colitis). Overall, 38.4% (10/26) have achieved either response or remission including 53% in Dose B alone (9/17). Although all Dose B subjects had pTreg expansion, Treg expansion in the colonic mucosa was not necessary for clinical response. Conclusion LD SC IL-2 was well tolerated and associated with a biological response and pTreg expansion in patients with moderate-to-severe UC. 1x106 IU/m2 was found to be the MED.

A Novel Next-Generation FVIII Mimetic, Mim8, Has a Favourable Safety Profile. Results from a 26-Week Safety Study in Cynomolgus Monkeys

Introduction Mim8 is in clinical development as a novel, next generation FVIII mimetic for subcutaneous prophylactic treatment for people with Hemophilia A (HA) with and without inhibitors. Mim8 is a fully human bispecific antibody bridging FIXa and FX. Mim8 showed approximately 15-fold higher potency compared to a sequence identical analogue (SIA) of the FVIII mimetic emicizumab (Hemlibra®) in thrombin generation assays (TGAs) and in vivo in mouse bleeding models (Kjellev et al., 2019; Ley et al. 2020). Mim8 binds to cynomolgus monkey and human FIX and FX with comparable affinities, and the pharmacological activity of Mim8 in cynomolgus monkeys was demonstrated both in vitro in TGA and in vivo in a cynomolgus bleeding model (Ley et al., 2020). The present study examined the safety and ex vivo pharmacodynamic effects of Mim8 in cynomolgus monkeys after weekly dosing for 26 weeks. Material and Methods Sexually mature cynomolgus monkeys were dosed subcutaneously (SC) with Mim8 at dose-levels of 0, 0.3, 1 or 3 mg/kg/week (4 males and 4 females at each dose-level) for 26 weeks. These dose-levels were chosen based on a previous 13-week safety study showing histopathological changes consistent with exaggerated pharmacology in a few animals dosed ≥6 mg/kg/week. During the study, the animals were monitored clinically and blood was sampled for measurement of standard clinical pathology, Mim8 exposure, anti-drug antibodies (ADA). The pharmacodynamic activity was assessed by ex vivo TGA in plasma under antibody-induced HA-like conditions and measurement of activated partial thromboplastin time (aPTT). After 26 weeks of exposure, the animals were euthanised, followed by macroscopic and microscopic pathological examination on all major organ systems. Results Weekly dosing with Mim8 at dose-levels up to 3 mg/kg/week for 26 weeks was well tolerated and the macroscopic and microscopic pathological examinations revealed no thrombi or other signs of excessive coagulation activation. In accordance, no significant changes in platelet counts, fibrinogen concentration or prothrombin time were observed. A pharmacodynamic effect was observed in dosed animals as a dose-dependent increase in ex vivo thrombin generation (TG; Figure 1) and shortening of aPTT. The steady state exposure increased with increasing dose level in a dose-proportional manner, reaching concentrations at least 10-fold above the expected clinical concentrations. However, as expected when dosing a human antibody to monkeys, ADAs developed in approximately half of the animals at all dose levels, leading to lack of exposure and reversal of the aPTT and TG towards the predose levels. Conclusion In conclusion, administration of up to 3 mg/kg/week Mim8 to cynomolgus monkeys for 26 weeks showed relevant pharmacodynamic effect and was well tolerated with no observation of thrombi or other signs of excessive coagulation activation, providing a favourable safety ratio to expected clinical exposure levels. Mim8 is currently being evaluated in a clinical Phase 1/2 trial. References Kjellev SL et al. (2019) Mim8 - a next-generation FVIII mimetic bi-Specific antibody - potently restores the hemostatic capacity in hemophilia a settings in vitro and in vivo. Blood, 134 (Supplement 1): 96. Ley CD et al. (2020) Improved effect of Mim8, a next-generation FVIII mimetic, translates from human in vitro to humanized mouse and cynomolgus models. European Association for Haemophilia and Allied Disorders (EAHAD 2020). Haemophilia, 26 (S2), P028. Disclosures Kjalke: Novo Nordisk A/S: Current Employment, Current equity holder in publicly-traded company.

Vesatolimod, a Toll-like Receptor 7 Agonist, Induces Immune Activation in Virally Suppressed Adults Living With Human Immunodeficiency Virus–1

Treatment with vesatolimod, an investigational, oral, toll-like receptor 7 (TLR7) agonist, leads to sustained viral remission in some non-human primates when combined with anti-envelope antibodies or therapeutic vaccines. We report results of a Phase Ib study evaluating safety, pharmacokinetics, and pharmacodynamics of vesatolimod in adults living with human immunodeficiency virus (HIV)-1. In this double-blind, multicenter, placebo-controlled trial, participants on antiretroviral therapy with screening plasma HIV-1 RNA levels <50 copies/mL were randomized (6:2) to receive 6-10 doses of vesatolimod (1-12 mg) or matching placebo orally every other week in sequential dose-escalation cohorts. The primary study objectives included establishing the safety and virologic effects of vesatolimod (change from baseline in plasma HIV-1 RNA). Pharmacokinetics and pharmacodynamic/immunologic activity were assessed as secondary objectives. A total of 48 individuals were randomly assigned to vesatolimod (n = 36) or placebo (n = 12). Vesatolimod was generally well tolerated, with no study drug-related serious adverse events or adverse events leading to study drug discontinuation. There were no statistically significant changes from baseline in plasma HIV-1 RNA in the vesatolimod groups, compared to placebo.Vesatolimod plasma exposures increased dose proportionally; consistent responses in cytokines, interferon-stimulated gene expression, and lymphocyte activation were observed with increasing dose levels above 4 mg. Peak elevations 24 hours after receipt of a 6 mg dose were >3.9-fold higher for interferon gamma-induced protein 10 (IP-10), interleukin-1 receptor antagonist (IL-1RA), interferon-inducible T-cell alpha chemoattractant (ITAC) when compared to baseline values. Vesatolimod was well tolerated at doses ranging from 1 to 12 mg. Immune stimulation was observed at doses above 4 mg, providing rationale for future combination trials in people living with HIV. NCT02858401.