Tested Dose Range Research Articles

Overview of the Clinical Pharmacology of Ertugliflozin, a Novel Sodium-Glucose Cotransporter 2 (SGLT2) Inhibitor.

Ertugliflozin, a selective inhibitor of sodium-glucose cotransporter 2 (SGLT2), is approved in the US, EU, and other regions for the treatment of adults with type 2 diabetes mellitus (T2DM). This review summarizes the ertugliflozin pharmacokinetic (PK) and pharmacodynamic data obtained during phase I clinical development, which supported the registration and labeling of this drug. The PK of ertugliflozin was similar in healthy subjects and patients with T2DM. Oral absorption was rapid, with time to peak plasma concentrations (Tmax) occurring at 1 h (fasted) and 2 h (fed) postdose. The terminal phase half-life ranged from 11 to 18 h and steady-state concentrations were achieved by 6 days after initiating once-daily dosing. Ertugliflozin exposure increased in a dose-proportional manner over the tested dose range of 0.5–300 mg. Ertugliflozin is categorized as a Biopharmaceutical Classification System Class I drug with an absolute bioavailability of ~ 100% under fasted conditions. Administration of the ertugliflozin 15 mg commercial tablet with food resulted in no meaningful effect on ertugliflozin area under the plasma concentration–time curve (AUC), but decreased peak concentrations (Cmax) by 29%. The effect on Cmax is not clinically relevant and ertugliflozin can be administered without regard to food. Mild, moderate, and severe renal impairment were associated with a ≤ 70% increase in ertugliflozin exposure relative to subjects with normal renal function, and no dose adjustment in renal impairment patients is needed based on PK results. Consistent with the mechanism of action of SGLT2 inhibitors, 24-h urinary glucose excretion decreased with worsening renal function. In subjects with moderate hepatic impairment, a decrease in AUC (13%) relative to subjects with normal hepatic function was observed and not considered clinically relevant. Concomitant administration of metformin, sitagliptin, glimepiride, or simvastatin with ertugliflozin did not have clinically meaningful effects on the PK of ertugliflozin or the coadministered medications. Coadministration of rifampin decreased ertugliflozin AUC and Cmax by 39% and 15%, respectively, and is not expected to affect efficacy in a clinically meaningful manner. This comprehensive evaluation supports administration to patients with T2DM without regard to prandial status and with no dose adjustments for coadministration with commonly prescribed drugs, or in patients with renal impairment or mild-to-moderate hepatic impairment based on ertugliflozin PK.

Magnetite-assisted in situ microbial oxidation of H2S to S0 during anaerobic digestion: A new potential for sulfide control

Direct interspecies electron transfer (DIET) between exoelectrogenic fatty acid-oxidizing bacteria and electrotrophic methanogens has recently been discovered, and studies have suggested that promoting DIET by adding electrically conductive material can effectively enhance the methanogenic performance and stability of anaerobic digestion (AD). This study investigated the effect of conductive magnetite (Fe3O4) addition on the AD of a sulfur-rich organic waste mixture, with an emphasis on the fate of sulfur and on H2S production. In contrast to previous findings, methanogenic performance under magnetite-added conditions was not significantly enhanced within the tested dose range of up to 20 mM Fe. When magnetite was added, H2S production decreased remarkably along with the extracellular accumulation of S0. Moreover, the H2S content in biogas was below 100 ppmv at magnetite doses of 8 mM Fe or higher (>6000 ppmv under control conditions, i.e., without magnetite). The reduced H2S production appears to be due to the anaerobic oxidation of sulfide to S0 because sulfate reduction remained active, whereas FeS was not produced under magnetite-added conditions. Based on microbial community analysis results and thermodynamic calculations, the electric syntrophy via DIET between exoelectrogenic anaerobic sulfide-oxidizing bacteria and electrotrophic methanogens is suggested to have been promoted by magnetite. To the best of our knowledge, this study is the first to propose an electro-syntrophic association that couples the oxidation of sulfide to S0 with the reduction of CO2 to CH4 in methanogenic environments. The present findings open a new possibility for in situ H2S control and sulfur recovery in AD processes for sulfur-rich waste treatment.

The effect of injected dose on localized tumor accumulation and cardiac uptake of doxorubicin in a Vx2 rabbit tumor model using MR-HIFU mild hyperthermia and thermosensitive liposomes

Purpose When doxorubicin (DOX) is administered via lyso-thermosensitive liposomes (LTLD), mild hyperthermia enhances localized delivery to heated vs. unheated tumors. The optimal LTLD dose and the impact of different doses on systemic drug distribution are unknown. Materials and methods: In this study, we evaluated local and systemic DOX delivery with three LTLD doses (0.1, 0.5, and 2.5 mg/kg) in a Vx2 rabbit tumor model. Temporally and spatially accurate controlled hyperthermia was achieved using a clinical MR-HIFU system for the intended heating duration (40 min). Results: DOX concentration in tissues delivered from LTLD combined with MR-HIFU mild hyperthermia are dose-dependent, including heated/unheated tumor, heart, and other healthy organs. Higher DOX accumulation and tumor-to-heart drug concentration ratio, defined as the ratio of DOX delivered into the tumor vs the heart, were observed in heated tumors compared to unheated tumors in all three tested doses. The DOX uptake efficiency for each mg/kg of LTLD injected IV of heated tumor was significantly higher than that of unheated tumor and heart within the tested dose range (0.1-2.5 mg/kg). The DOX uptake for the heart linearly scaled up as a function of dose while that for the heated tumor showed some evidence of saturation at the high dose of 2.5 mg/kg. Conclusions: These results provide guidance on clinical protocol design of hyperthermia-triggered drug delivery.

Caffeic Acid Phenethyl Ester and Its Fluorinated Derivative as Natural Anti-obesity Agents (P06-089-19)

ObjectivesCaffeic acid phenethyl ester (CAPE), an active component of propolis from honeybee hives, is well studied for its beneficial effects on cancer, inflammation and diabetes. There are however limited studies investigating the effects of CAPE on obesity. Currently, several natural products are under investigation for their effects on adipocyte life cycle. A multi-targeted approach for prevention and treatment of obesity includes targeting adipocytes at all the stages of life cycle by decreasing adipocyte differentiation, inducing lipolysis and/or by inducing adipocyte apoptosis. In this study, we examined the effects of CAPE on preadipocyte viability, adipogenesis and lipolysis. Earlier reports on CAPE indicate that CAPE is liable to enzymatic hydrolysis in vivo making this compound unstable for therapeutic applications. In the current study, we compared the anti-adipogenic effects of CAPE with its novel fluorinated derivative (FCAPE), a more stable compound. Methods3T3-L1 pre-adipocytes were differentiated using a cocktail consisting of insulin, dexamethasone, and isobutyl methyl xanthine in DMEM supplemented with 10% FBS following adipogeneic differentiation. Pre- and mature adipocytes were incubated with CAPE or FCAPE for 24–48 hours and their effects on viability, lipolysis, and adipogenesis was tested using Prestoblue, Lipolysis assay (Zen-Bio) and AdipoRed assay respectively. ResultsOur results indicate that neither CAPE nor FCAPE significantly altered preadipocyte viability within the tested dose range. Although both CAPE and FCAPE significantly decreased adipogenesis compared to control, FCAPE decreased lipid content by 73.6 ± 1.6% while CAPE reduced lipid content by only 36.8 ± 9.1% at 25 μM concentration. In contrast to adipogenesis data, our preliminary results with lipolysis assay indicate that only CAPE, but not FCAPE induces lipolysis in mature adipocytes. ConclusionsThese findings suggest that both CAPE and FCAPE possess anti-adipogenic properties. Further studies are needed to elucidate their differential effects on adipogenesis and lipolysis. Funding SourcesThis study was funded by the Department of Research, PCOM.

Carbaryl Modulates Chronobiological Behaviors via Melatonin Receptors

Humans are exposed to low levels of carbaryl and other carbamate insecticides found in household products, food, and water due to persistent and widespread use. Environmental and occupational exposure to carbamate pesticides is linked to metabolic disorders and sleep apnea, though it is not clear which biological targets contribute to disease pathology (Montgomery et al. 2008; James‐Todd et al., 2016; Baumert et al. 2017). Carbaryl binds to MT1 and MT2 G protein‐coupled receptors with varying efficacies and potencies as demonstrated by our team via in‐silico molecular modeling and in‐vitro bioassays (Popovska‐Gorevski et al. 2017; Jones et al. 2017 EB Abst; Glatfelter et al. 2017 EB Abst). We hypothesize that carbaryl may produce alterations in circadian rhythms through interactions with melatonin receptors that could contribute to the aforementioned disease symptomology, progression, and/or pathologies. Previous in‐vitro (1–100μM) and ex‐vivo (10 mg/kg, i.p.) experiments demonstrated specificity for competition of carbaryl for 2‐[125I]‐iodomelatonin binding to brain melatonin receptors and its ability to reach target brain areas controlling circadian rhythms in‐vivo (e.g. suprachiasmatic nucleus: SCN; Glatfelter et al. 2017 EB Abs). We tested the ability of carbaryl (10 mg/kg, i.p.) to phase shift onset of circadian running wheel activity when given at circadian time (CT) 10 (CT12 = onset of running wheel activity in constant dark) for 3 days in wild‐type C3H/HeN (C3H) mice. Our results indicate that carbaryl (0.81h ± 0.1; n=12; p<0.0001) and positive control melatonin (3mg/kg s.c.; 0.97h ± 0.2; n=4; p<0.001) significantly phase advance running wheel activity onset compared to vehicle (0.03h ± 0.04; n=7) treated controls (F2,20=18.46; p<0.05; Dunnet's Post Test). In the same paradigm, carbaryl (10 mg/kg i.p.) given 10 hrs before onset of running wheel activity in constant dark at CT 2 showed a phase delay (−1.2h ± 0.11; n=14; p<0.0001) similar to positive control melatonin (3mg/kg s.c. 1.3h ± 0.14; n=4; p<0.001) compared to vehicle (−0.12h ± 0.02; n=19) treated controls (F2,34=75.96; p<0.05; Dunnet's Post Test). These data demonstrate that carbaryl has the same periods of circadian sensitivity for phase shift at CT2 & CT10 as melatonin (Benloucif & Dubocovich 1996). A dose response curve for carbaryl (0.01 – 10 mg/kg i.p.) to phase advance circadian running wheel activity rhythms at CT10 reveals an ED50 value of 0.019 mg/kg, i.p. which is similar in magnitude to melatonin (ED50=0.024 mg/kg s.c. Dubocovich et al. 1998). Carbaryl (10 mg/kg i.p.) did not phase advance circadian running wheel activity rhythms in C3H MT1KO mice (−0.04h ± 0.04; n=18; n.s.) at CT10 compared to vehicle controls (−0.04h ± 0.03; n=19; t=0.12; n.s.) suggesting an MT1 dependent mechanism. We conclude that carbaryl phase shifts circadian activity rhythms via activation of MT1 melatonin receptors suggesting environmental or occupational exposure to this insecticide in the tested dose range could influence disease pathologies via modulation of circadian biology.Support or Funding InformationSupported by ES 023684 and UB Jacobs School of Medicine funds to MLD and RVR.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

The crosslinking behaviour of cellulose in gamma irradiated paper

The behaviour of cellulose-based materials in a relatively low gamma dose range (less than 10 kGy) is of interest for the application of ionizing radiation for the preservation of cultural heritage. Different relationships between the absorbed dose and number of scissions or degree of polymerization (DP) were established on a large dose range (over 100 kGy). The significant decrease of DP was confirmed for doses range of interest for cultural heritage preservation, for pure cellulose paper and other sorts of commercial paper. However, other physical properties of the paper have less or no change for irradiation at doses below 10 kGy.The purpose of this study is to evaluate the changes induced by gamma irradiation to the hydrogen bonds structure in cellulose, in a low dose interval, by thermal analysis and infrared spectroscopy.Our results confirm the crosslinking behaviour for Whatman paper at low irradiation doses. A similar behaviour was observed for copy paper but with reduced intensity and higher statistical errors. This behaviour can explain why mechanical resistance of irradiated paper remains unchanged below a certain dose, as previously reported in a number of studies. The carbonyl content shows a continuous increase over the tested dose range but the increase of carbonyl content in Whatman paper at doses lower than 10 kGy is lower than the initial carbonyl content of copy paper. The ionizing radiation treatment for cultural heritage is not nonintrusive in case of paper but the degradation risks are minimal for doses below 10 kGy.

Clinical Pharmacology of the Reversible and Potent P2Y12 Receptor Antagonist ACT‐246475 After Single Subcutaneous Administration in Healthy Male Subjects

ACT-246475 is a selective and reversible P2Y12 receptor antagonist inducing inhibition of platelet aggregation (IPA). A randomized, double-blind, placebo-controlled, parallel-design study was performed to investigate the safety, tolerability, pharmacokinetics, and pharmacodynamics of escalating single subcutaneous doses of ACT-246475 (1, 2, 4, 8, 16, or 32mg) in healthy male subjects (N=8 per dose, 3:1 active:placebo ratio). Pharmacodynamic effects were assessed based on maximum platelet aggregation and P2Y12 reaction units using light transmission aggregometry and VerifyNow® assays, respectively. ACT-246475 was safe and well tolerated up to 32mg based on adverse event data and absence of clinically relevant changes in hematology, biochemistry, vital signs, and electrocardiogram variables. Median time to reach maximum plasma concentration was 0.5-0.75hours, and geometric mean terminal half-life ranged from 1.3 to 9.2hours across the tested dose range. Exposure to ACT-246475 was dose proportional across all dose groups. The maximal %IPA was reached within 30minutes after subcutaneous administration of ACT-246475. A dose-dependent duration and extent of effect were observed based on area under the effect curve and maximum effect data. Similar results were observed for maximum platelet aggregation and P2Y12 reaction units. The %IPA was≥85% at doses≥2mg. This level of %IPA was extended to at least 12hours in the 32-mg dose group. The safety and pharmacokinetic/pharmacokinetic profile with quick onset and adequate duration of IPA support further investigation in patients with coronary artery disease.

The effect of pre-phototest sun exposure on minimal erythema dose and minimal melanogenic dose among skin phototypes III, IV and V.

Ethnicity, skin phototype and colour influenced minimal erythema dose (MED). Sun exposure has been postulated to increase MED. We determined immediate pigment darkening dose to UVA (IPDDA), MED and minimal melanogenic dose (MMD) for UVB and UVA, and investigated factors affecting these doses. Skin phototype was determined using Fitzpatrick phototype quiz, DSMII ColorMeter measured skin colours, sun exposure quantified using an index (SEI) and phototest performed with MEDlight-Multitester. A total of 167 healthy volunteers participated. There were 110 (66%) females and 56 (34%) males; 124 (74.7%) were Malay, 27 (16.3%) Chinese and 14 (8.4%) Indians. One hundred and nine (65.7%) skin phototype IV, 30 (18.1%) phototype III and 27 (16.3%) phototype V. IPDDA ranges from 6±1.5-5.7±1.4J/cm2 . MED-UVB were 96.9±17.6, 124±29.3 and 118.6±27.4mJ/cm2 for phototype III, IV and V, respectively. All MED-UVA were outside the tested dose range of 3.6-11J/cm2 . MMD-UVB were 106±18.2, 134±25.6 and 136±31.1mJ/cm2 while MMD-UVA were 4.1±4.1, 4.9±3.8 and 5.7±3.7J/cm2 respectively for phototypes III, IV and V. MED-UVB, MMD-UVB and MMD-UVA did not depend on skin phototype. Facultative skin whiteness (L*), erythema (E) and melanin content (M) correlated significantly with MED-UVB while constitutive skin colours were significant for L*, yellowness (b*), E and M. Sun exposure did not significantly correlate with MED-UVB and MMDs, however, an inverse relationship with MED-UVB was demonstrated. Minimal erythema doses in our cohort were slightly different from other regional countries. Constitutive and facultative skin whiteness, erythema and melanin content correlated with MED. There was no association between skin phototype and sun exposure with MED or MMD.

Gene Therapy with BMN 270 Results in Therapeutic Levels of FVIII in Mice and Primates and Normalization of Bleeding in Hemophilic Mice.

Hemophilia A is an X-linked bleeding disorder caused by mutations in the gene encoding the factor VIII (FVIII) coagulation protein. Bleeding episodes in patients are reduced by prophylactic therapy or treated acutely using recombinant or plasma-derived FVIII. We have made an adeno-associated virus 5 vector containing a B domain-deleted (BDD) FVIII gene (BMN 270) with a liver-specific promoter. BMN 270 injected into hemophilic mice resulted in a dose-dependent expression of BDD FVIII protein and a corresponding correction of bleeding time and blood loss. At the highest dose tested, complete correction was achieved. Similar corrections in bleeding were observed at approximately the same plasma levels of FVIII protein produced either endogenously by BMN 270 or following exogenous administration of recombinant BDD FVIII. No evidence of liver dysfunction or hepatocyte endoplasmic reticulum stress was observed. Comparable doses in primates produced similar levels of circulating FVIII. These preclinical data support evaluation of BMN 270 in hemophilia A patients.

Model-Based Assessment Using Conventional Bioequivalence Limits to Ensure Safety and Efficacy of Rivaroxaban in Patients Undergoing Hip or Knee Replacement.

We evaluated whether the current bioequivalence limit is adequate to ensure safety and efficacy of rivaroxabanin patients undertotal hip arthroplasty and total knee arthroplastybased on its model informed benefit/risk profile. Clinical data from a total of 7145 patients from 3 phase 2 and 4 phase 3 clinical trials were included in the current model-based exposure-response analysis. The relationships between rivaroxaban exposure measurements (ie,minimum or trough, maximum, average concentration, and area under the concentration-time curve [AUC] at steady state)and clinical outcomes (ie, the probabilities of major bleeding [MB] andvenous thromboembolism [VTE]) were modeled using NONMEM7.3.Model evaluation was performed using predictive checks and nonparametric bootstrap. Simulations were conducted to assess the study objectives.A shallow relationship was observed between explored exposure measurements within the tested dose range and the probability of VTE following rivaroxaban treatment.Trough concentrations were found to be a statistically significant predictor of the probability of MB. This relationship was better described using a power function. Model validation confirmed model adequacy. Based on the simulations results, the relative risk of MB of a hypothetical test product (with 20% change in AUC) will not statistically differ from the brand name drug.Twenty percentAUC variations do not change the relative risk of MB and is unlikely to compromise efficacy of therapy. A generic drug of rivaroxaban passing the typical bioequivalence assessment is expected to have similar safety and efficacy as the brand name drug.

Safety and in vivo immune assessment of escalating doses of oral laquinimod in patients with RRMS

BackgroundLaquinimod is an oral immunomodulator in clinical development to treat relapsing-remitting multiple sclerosis (RRMS). Laquinimod is in clinical development for the treatment of multiple sclerosis and Huntington Disease (HD). The objective of this study is to assess the safety, tolerability, pharmacokinetics (PK) and cytoimmunologic effects following escalating doses of laquinimod in patients with RRMS.MethodsOne hundred twelve patients were randomly assigned to laquinimod/placebo in a series of separate dose-escalating cohorts starting from a daily oral dose of 0.9 mg/1.2 mg escalating to 2.7 mg, in 0.3 mg increments.ResultsTwenty-eight patients received placebo and 84 received laquinimod ranging from 0.9 to 2.7 mg. No deaths occurred. One serious adverse event (SAE) of perichondritis was reported, which was unrelated to laquinimod (0.9 mg). There was no increased incidence of adverse events (AEs) with escalating doses. Laquinimod-treated patients showed more abnormal laboratory levels in liver enzymes, P-amylase, C-reactive protein (CRP), and fibrinogen, but most shifts were clinically non-significant. The exposure of laquinimod was dose proportional and linear in the tested dose range. An immunological substudy showed significant dose-dependent decreases in 6-sulpho LacNAc + dendritic cell (slanDC) frequency following laquinimod compared to placebo.ConclusionLaquinimod doses up to 2.7 mg were safely administered to patients with RRMS. An in vivo effect of laquinimod on the innate immune system was demonstrated.Trial registrationEudraCT Number: 2009-011234-99. Registered 23 June 2009.

Abstract CT092: Pharmacokinetics of a THIOMABTM antibody drug conjugate (TDC): DMUC4064A in a phase 1 study with platinum-resistant ovarian cancer

Abstract BACKGROUND: DMUC4064A is a TDC comprising a humanized anti-MUC16 IgG1 and a potent anti-mitotic agent, monomethyl auristatin E (MMAE) through a protease-labile linker through engineered cysteine at a Drug Antibody Ratio (DAR) of 2. The use of engineered cysteines is intended to allow more homogenous conjugation, which in turn can improve the overall performance of the TDC (i.e. slower clearance), compared to the conventional ADC (prepared by stochastic conjugation to interchain disulfide bond cysteines). MUC16 is a transmembrane glycoprotein overexpressed on ovarian cancer cells, which in its soluble form is known as Carbohydrate antigen 125 (CA125). A phase I study in PROC patients is ongoing to assess the safety, efficacy and PK of DMUC4064A given every 3 weeks (Q3W). METHODS: Serum/plasma samples at multiple time points were quantified for three analytes (unconjugated MMAE, DMUC4064A total antibody (tAb), and DMUC4064A conjugate (measured as antibody-conjugated MMAE, acMMAE)). The cycle 1 PK was assessed by standard non-compartmental analysis. The impact of serum CA125 on PK was investigated. RESULTS: Within the tested dose range (1.0-5.6 mg/kg), acMMAE and tAb showed nonlinear PK with more than dose-proportional exposure at the higher doses (4.8 mg/kg and 5.6 mg/kg). A clear correlation of acMMAE with tAb exposure was observed. The PK of DMUC4064A at the highest dose tested (5.6 mg/kg), as measured by acMMAE, showed a volume of distribution of approximately 52 mL/kg and a clearance of ~7 mL/day/kg with a terminal half-life of approximately 5.5 days. Unconjugated MMAE exposure was consistently lower than acMMAE with a mean Cmax approximately 150-300 fold lower than that of acMMAE. At higher doses (>4.0 mg/kg), unconjugated MMAE exposure was variable and overlapping across doses. Accumulation of all analytes was minimal after repeated dosing (Q3W). Based on preliminary data from this ongoing study, baseline CA125 levels have not shown any apparent impact on cycle 1 exposure. Compared to the conventional anti-MUC16 ADC (DMUC5754A, DAR 3.5) at 2.4 mg/kg (MTD), the TDC DMUC4604A at 5.6 mg/kg demonstrates a greater than 3 fold slower acMMAE clearance1. CONCLUSION: In this ongoing study of DMUC4604A, nonlinear PK of acMMAE and tAb were observed over the dose range studied, and exposures of acMMAE and tAb were highly correlated. This is the first report of clinical PK data of a TDC demonstrating slower clearance compared to a conventional ADC format. 1 Liu JF, et al. Annals of Oncology 27: 2124–2130, 2016 Citation Format: Amit Garg, Gaohong She, Ian Donatello, Matts Kagedal, Douglas D. Leipold, Ola Saad, Joyce Liu, Kathleen Moore, Erika Hamilton, Howard Burris, Judy Wang, Michael Birrer, Eric Humke, Sandhya Girish. Pharmacokinetics of a THIOMABTM antibody drug conjugate (TDC): DMUC4064A in a phase 1 study with platinum-resistant ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr CT092. doi:10.1158/1538-7445.AM2017-CT092

The effects of the concentration-dependent erythrocyte distribution of TAK-802, a potent acetylcholinesterase inhibitor, on rat pharmacokinetics.

The purpose of this study was to investigate the effect of the concentration-dependent erythrocyte distribution of TAK-802, a potent acetylcholinesterase inhibitor, on rat pharmacokinetics. In an ascending oral dose study, the maximum plasma concentration (Cmax ) of TAK-802 increased in a dose-dependent manner. The time to reach Cmax decreased as the dose increased, whereas the total clearance was independent of the tested dose range. In this intravenous (i.v.) ascending dose study in rats, the apparent distribution volumes at steady state decreased, and the apparent terminal elimination rate constants increased with TAK-802 dose escalation. A marked concentration dependency was observed in an associated in vitro erythrocyte distribution study. The in vitro erythrocyte distribution study results and a relationship analysis between the plasma and blood concentrations of TAK-802 after i.v. dosing revealed that the characteristics of the erythrocyte distribution could be expressed by Langmuir's adsorption formula. The concentration-time profiles of TAK-802 in plasma and whole blood calculated using a nonlinear pharmacokinetic model incorporating the concentration-dependent erythrocyte distribution with optimized parameters fit well to the observed plasma and blood concentration profiles obtained from the i.v. ascending dose study. These results indicate that the concentration-dependent erythrocyte distribution plays a major role in the nonlinear pharmacokinetics of TAK-802 in rats. Copyright © 2016 John Wiley & Sons, Ltd.

A novel cyclic dipeptide from deep marine-derived fungus Aspergillus sp. SCSIOW2

A novel cyclic dipeptide, 14-hydroxy-cyclopeptine (1), was purified from a deep sea derived fungal isolate identified as an Aspergillus sp. The structure was elucidated by detailed spectroscopic analyses using 1D and 2D NMR experiments and high resolution mass spectrometry. The absolute configuration of the amino acid was determined by Marfey's method. Two conformational isomers of 1 were established by ROE analyses. 1 inhibited nitric oxide production with IC50 values at 40.3 μg/mL in a lipopolysaccharide and recombinant mouse interferon-γ -activated macrophage-like cell line, RAW 264.7 and showed no cytotoxic effect in the tested dose range up to 100 μg/mL.

Mechanical hyperalgesia in rats with diabetic polyneuropathy is selectively inhibited by local peripheral nociceptin/orphanin FQ receptor and µ-opioid receptor agonism

Peripheral receptors may contribute to the effects of systemically administered centrally available analgesics. In the present study, we analysed the effect of local peripheral injection of the nociceptin/orphanin FQ peptide (NOP) receptor agonist Ro65-6570 and compared it to the µ-opioid peptide (MOP) receptor agonist morphine in streptozotocin-induced diabetic polyneuropathy in rats. Ro65-6570 and morphine were injected intraplantarly into the hind paw of diabetic rats, and mechanical withdrawal thresholds were determined in both paws (ipsi- and contralateral to the injection site). Ro65-6570 in the dose range of 7.1–71.4nmol/animal showed antihyperalgesic effects with maximal efficacy of 57.1±15.4% maximal possible effect (MPE) at the dose of 23.8nmol/animal. Intraplantar administration of morphine showed dose-dependent antihyperalgesic effects in the dose range of 25.8–257.8nmol/animal in a similar efficacy range with a maximal efficacy of 76.0±12.1% MPE at the dose of 257.8nmol/animal. Both compounds did not induce overt confounding side effects across the tested dose range. The NOP receptor antagonist J-113397 and the MOP receptor antagonist naloxone, intraplantarly co-administered with the respective agonists, selectively and completely prevented the antihyperalgesic action of the respective NOP and MOP receptor agonist. These results indicate that the activation of peripheral NOP and MOP receptors by Ro65-6570 and morphine, respectively, mediated antihyperalgesic effects in rats with diabetic polyneuropathy.

Dose-dependent establishment of Trichuris suis larvae in Göttingen minipigs

Embryonated eggs of the pig whipworm Trichuris suis (TSOee) constitute the active pharmaceutical ingredient (API) in a medicinal product explored in human clinical trials against several immune-mediated diseases. The measurement of TSO biological potency (hatchability and infectivity) is a requirement for the assessment of TSO's pharmacological potency in human clinical trials. The present study aims to validate the dose-dependent establishment of T. suis larvae in Göttingen minipigs and eventual clinical implication of a dose range (1000–10,000 TSO). Four groups of 5 minipigs were inoculated with doses of 1000, 2500, 7500, and 10,000 TSOee, respectively, to evaluate a range of concentrations of TSOee in a minipig infectivity model. Unembryonated eggs (TSOue) were added to keep the total egg number in the inoculum constant at 10,000 eggs. Two groups received 2500 and 7500 TSOee per pig without the addition of TSOue as controls. The intestinal larval establishment at 21 days post inoculation (dpi) demonstrated a clear positive linear dose–response relationship between numbers of inoculated TSOee and recovered larvae. There was a low level of variation in larval counts in all study groups. Thus, the infectivity model in minipigs within the tested dose range offers a reliable, sensitive and accurate assay for testing biological potency of TSO.

Effects of prostacyclin on cerebral blood flow and vasospasm after subarachnoid hemorrhage: randomized, pilot trial.

Delayed ischemic neurological deficits (DINDs) are a major contributing factor for poor outcome in patients with subarachnoid hemorrhage. In this trial, we investigated the therapeutic potential of prostacyclin, an endogen substance with known effect on vascular tone and blood flow regulation, on factors related to DIND. This trial is a single-center, randomized, blinded, clinical, pilot trial with 3 arms. Ninety patients were randomized to continuous infusion of prostacyclin 1 ng/kg per minute, prostacyclin 2 ng/kg per minute, or placebo. The intervention was initiated day 5 after subarachnoid hemorrhage and discontinued day 10. Primary outcome was the difference in change from baseline in global cerebral blood flow. Secondary outcome measures were occurrence of DIND, angiographic vasospasm, and clinical outcome at 3 months. No statistically significant difference in change of global cerebral blood flow was found between the intervention groups. The observed incidence of DIND and angiographic vasospasm was markedly higher in the placebo group, although this difference was not statistically significant. No statistically significant differences in safety parameters or clinical outcome were found between the 3 groups. Administration of prostacyclin to patients with subarachnoid hemorrhage may be safe and feasible. Global cerebral blood flow after subarachnoid hemorrhage is not markedly affected by administration of prostacyclin in the tested dose range. It may be possible that the observed reduction in the point estimates of DIND and vasospasm in the prostacyclin groups represents an effect of prostacyclin as this trial was not powered to investigate the effect of prostacyclin on these outcomes. http://www.clinicaltrials.gov. Unique identifier: NCT01447095.

Bayesian designs of phase II oncology trials to select maximum effective dose assuming monotonic dose-response relationship.

BackgroundFor many molecularly targeted agents, the probability of response may be assumed to either increase or increase and then plateau in the tested dose range. Therefore, identifying the maximum effective dose, defined as the lowest dose that achieves a pre-specified target response and beyond which improvement in the response is unlikely, becomes increasingly important. Recently, a class of Bayesian designs for single-arm phase II clinical trials based on hypothesis tests and nonlocal alternative prior densities has been proposed and shown to outperform common Bayesian designs based on posterior credible intervals and common frequentist designs. We extend this and related approaches to the design of phase II oncology trials, with the goal of identifying the maximum effective dose among a small number of pre-specified doses.MethodsWe propose two new Bayesian designs with continuous monitoring of response rates across doses to identify the maximum effective dose, assuming monotonicity of the response rate across doses. The first design is based on Bayesian hypothesis tests. To determine whether each dose level achieves a pre-specified target response rate and whether the response rates between doses are equal, multiple statistical hypotheses are defined using nonlocal alternative prior densities. The second design is based on Bayesian model averaging and also uses nonlocal alternative priors. We conduct simulation studies to evaluate the operating characteristics of the proposed designs, and compare them with three alternative designs.ResultsIn terms of the likelihood of drawing a correct conclusion using similar between-design average sample sizes, the performance of our proposed design based on Bayesian hypothesis tests and nonlocal alternative priors is more robust than that of the other designs. Specifically, the proposed Bayesian hypothesis test-based design has the largest probability of being the best design among all designs under comparison and the smallest probability of being an inadequate design, under sensible definitions of the best design and an inadequate design, respectively.ConclusionsThe use of Bayesian hypothesis tests and nonlocal alternative priors under ordering constraints between dose groups results in a robust performance of the design, which is thus superior to other common designs.

The Selective Glycine Uptake Inhibitor Org 25935 as an Adjunctive Treatment to Atypical Antipsychotics in Predominant Persistent Negative Symptoms of Schizophrenia

Using a selective glycine uptake inhibitor as adjunctive to second-generation antipsychotic (SGA) was hypothesized to ameliorate negative and/or cognitive symptoms in subjects with schizophrenia. Subjects with predominant persistent negative symptoms (previously stabilized ≥3 months on an SGA) were enrolled in a randomized, placebo-controlled trial to investigate adjunctive treatment with Org 25935, a selective inhibitor of type 1 glycine transporter, over 12 weeks in a flexible dose design. Org 25935 was tested at 4 to 8 mg twice daily and 12 to 16 mg twice daily versus placebo. Primary efficacy outcome was mean change from baseline in Scale for Assessment of Negative Symptoms composite score. Secondary efficacy end points were Positive and Negative Syndrome Scale total and subscale scores, depressive symptoms (Calgary Depression Scale for Schizophrenia), global functioning (Global Assessment of Functioning scale), and cognitive measures using a computerized battery (Central Nervous System Vital Signs). Responder rates were assessed post hoc. A total of 215 subjects were randomized, of which 187 (87%) completed the trial. Both dose groups of Org 25935 did not differ significantly from placebo on Scale for Assessment of Negative Symptoms, Positive and Negative Syndrome Scale (total or subscale scores), Global Assessment of Functioning, or the majority of tested cognitive domains. Org 25935 was generally well tolerated within the tested dose range, with no meaningful effects on extrapyramidal symptoms and some reports of reversible visual adverse effects. Org 25935 did not differ significantly from placebo in reducing negative symptoms or improving cognitive functioning when administered as adjunctive treatment to SGA. In our study population, Org 25935 appeared to be well tolerated in the tested dose ranges.

Phase I Study of Clofarabine in Adult Patients with Acute Myeloid Leukemia in Japan

There are limited treatment options for relapsed/refractory acute myeloid leukemia patients or previously untreated elderly (≥60 years) patients with acute myeloid leukemia. In Phase II studies from the USA and Europe, single-agent clofarabine demonstrated activity and acceptable toxicity in elderly patients with previously untreated acute myeloid leukemia. This Phase I, multicenter study assessed the maximum-tolerated dose, safety, pharmacokinetics and efficacy of clofarabine in Japanese adults with acute myeloid leukemia. Intravenous clofarabine (20, 30 and 40 mg/m(2)/day) was administered for 5 days to Japanese adult patients with relapsed or refractory acute myeloid leukemia or elderly patients with newly diagnosed acute myeloid leukemia. Fourteen patients, median age of 67.5 (59-72) years, were enrolled in this study. Eleven out of 14 patients had relapsed/refractory acute myeloid leukemia. Three patients received clofarabine at 20 mg/m(2), six at 30 mg/m(2) and five at 40 mg/m(2). Frequently reported treatment-related adverse events included thrombocytopenia (100%), anemia (93%), neutropenia (86%), nausea (86%), alanine aminotransferase increase (71%), headache (71%) and febrile neutropenia (57%). Three patients experienced reversible dose-limiting toxicities; two had increased alanine aminotransferase with 30 and 40 mg/m(2) and one had Grade 3 elevation of serum amylase with 40 mg/m(2). The maximum-tolerated dose was 30 mg/m(2)/day. Cmax and exposure area under the curve0-24h increased with increasing dose and were proportional to dose through the tested dose range. Among the 14 assessable patients, four (29%) achieved complete remission and two (14%) complete remission without platelet recovery. The overall remission rate was 43%. These results demonstrate safety and preliminary, promising activity of clofarabine in Japanese patients with acute myeloid leukemia. Further investigation is warranted.