scholarly journals In VitroandIn VivoPharmacokinetics of Aminoalkylated Diarylpropanes NP085 and NP102

2016 ◽  
Vol 60 (5) ◽  
pp. 3065-3069 ◽  
Author(s):  
Liezl Gibhard ◽  
Kendrekar Pravin ◽  
Efrem Abay ◽  
Anke Wilhelm ◽  
Kenneth Swart ◽  
...  
Keyword(s):  
Liver Microsomes ◽  
Hepatic Metabolism ◽  
Pharmacokinetic Studies ◽  
Time Intervals ◽  
Content Type ◽  
Drug Concentrations ◽  
Elimination Half ◽  
Liquid Chromatography Tandem Mass ◽  
The University

ABSTRACTMalaria remains a great burden on humanity. Although significant advances have been made in the prevention and treatment of malaria, malaria control is now hindered by an increasing tolerance of the parasite to one or more drugs within artemisinin combination therapies; therefore, an urgent need exists for development of novel and improved therapies. The University of the Free State Chemistry Department previously synthesized an antimalarial compound, NP046.In vitrostudies illustrated an enhanced efficacy againstPlasmodium falciparum. However, NP046 showed low bioavailability. Efforts to enhance the bioavailability of NP046 have resulted in the synthesis of a number of aminoalkylated diarylpropanes, including NP085 and NP102. Pharmacokinetic studies were conducted in C57BL/6 mice, with 15 mg/kg NP085 or NP102 administered orally and the 5 mg/kg NP085 or NP102 administered intravenously. Blood samples were collected by means of tail bleeding at predetermined time intervals. Drug concentrations were determined using a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, and subsequently pharmacokinetic modeling was done for both compounds. NP085 and NP102 were incubatedin vitrowith human and mouse liver microsomes. Both compounds were also subjected to a parallel artificial membrane permeation assay.In vitrostudies of NP085 and NP102 illustrated that both of the compounds are rapidly absorbed and undergo rapid hepatic metabolism. The maximum concentration of drug (Cmax) obtained following oral administration of NP085 and NP102 was 0.2 ± 0.4 and 0.7 ± 0.3 μM, respectively; the elimination half-life of both compounds was 6.1 h. NP085 and NP102 showed bioavailability levels of 8% and 22%, respectively.

scholarly journals In Vitro Human Onychopharmacokinetic and Pharmacodynamic Analyses of ME1111, a New Topical Agent for Onychomycosis

2017 ◽  
Vol 62 (1) ◽  
Author(s):  
Natsuki Kubota-Ishida ◽  
Naomi Takei-Masuda ◽  
Kaori Kaneda ◽  
Yu Nagira ◽  
Tsubasa Chikada ◽  
...  
Keyword(s):  
Antifungal Agent ◽  
Antifungal Agents ◽  
Nail Plate ◽  
Free Drug ◽  
Content Type ◽  
Clinical Dose ◽  
Drug Concentrations ◽  
Liquid Chromatography Tandem Mass ◽  
Human Nails

ABSTRACT ME1111 is a novel antifungal agent currently under clinical development as a topical onychomycosis treatment. A major challenge in the application of topical onychomycotics is penetration and dissemination of antifungal agent into the infected nail plate and bed. In this study, pharmacokinetic/pharmacodynamic parameters of ME1111 that potentially correlate with clinical efficacy were compared with those of marketed topical onychomycosis antifungal agents: efinaconazole, tavaborole, ciclopirox, and amorolfine. An ME1111 solution and other launched topical formulations were applied to an in vitro dose model for 14 days based on their clinical dose and administration. Drug concentrations in the deep layer of the nail and within the cotton pads beneath the nails were measured using liquid chromatography-tandem mass spectrometry. Concentrations of ME1111 in the nail and cotton pads were much higher than those of efinaconazole, ciclopirox, and amorolfine. Free drug concentrations of ME1111 in deep nail layers and cotton pads were orders of magnitude higher than the MIC90 value against Trichophyton rubrum (n = 30). Unlike other drugs, the in vitro antifungal activity of ME1111 was not affected by 5% human keratin and under a mild acidic condition (pH 5.0). The in vitro antidermatophytic efficacy coefficients (ratio of free drug concentration to MIC90s against T. rubrum) of ME1111, as measured in deep nail layers, were significantly higher than those of efinaconazole, tavaborole, ciclopirox, and amorolfine (P < 0.05). This suggests that ME1111 has excellent permeation of human nails and, consequently, the potential to be an effective topical onychomycosis treatment.

scholarly journals Characterization of the Preclinical Pharmacology of the New 2-Aminomethylphenol, JPC-3210, for Malaria Treatment and Prevention

2018 ◽  
Vol 62 (4) ◽  
Author(s):  
Geoffrey W. Birrell ◽  
Gavin D. Heffernan ◽  
Guy A. Schiehser ◽  
John Anderson ◽  
Arba L. Ager ◽  
...  
Keyword(s):  
Oral Bioavailability ◽  
Half Life ◽  
Antimalarial Activity ◽  
Dose Range ◽  
Liver Microsomes ◽  
Content Type ◽  
Elimination Half Life ◽  
Elimination Half

ABSTRACTThe new 2-aminomethylphenol, JPC-3210, has potentin vitroantimalarial activity against multidrug-resistantPlasmodium falciparumlines, low cytotoxicity, and highin vivoefficacy against murine malaria. Here we report on the pharmacokinetics of JPC-3210 in mice and monkeys and the results ofin vitroscreening assays, including the inhibition of cytochrome P450 (CYP450) isozymes. In mice, JPC-3210 was rapidly absorbed and had an extensive tissue distribution, with a brain tissue-to-plasma concentration ratio of about 5.4. JPC-3210 had a lengthy plasma elimination half-life of about 4.5 days in mice and 11.8 days in monkeys. JPC-3210 exhibited linear single-oral-dose pharmacokinetics across the dose range of 5 to 40 mg/kg of body weight with high oral bioavailability (∼86%) in mice. Systemic blood exposure of JPC-3210 was 16.6% higher inP. berghei-infected mice than in healthy mice.In vitrostudies with mice and human hepatocytes revealed little metabolism and the high metabolic stability of JPC-3210. The abundance of human metabolites from oxidation and glucuronidation was 2.0% and 2.5%, respectively. CYP450 studies in human liver microsomes showed JPC-3210 to be an inhibitor of CYP2D6 and, to a lesser extent, CYP3A4 isozymes, suggesting the possibility of a metabolic drug-drug interaction with drugs that are metabolized by these isozymes.In vitrostudies showed that JPC-3210 is highly protein bound to human plasma (97%). These desirable pharmacological findings of a lengthy blood elimination half-life, high oral bioavailability, and low metabolism as well as highin vivopotency have led the Medicines for Malaria Venture to select JPC-3210 (MMV892646) for further advanced preclinical development.

scholarly journals Evaluation of Ceftaroline Alone and in Combination against Biofilm-Producing Methicillin-Resistant Staphylococcus aureus with Reduced Susceptibility to Daptomycin and Vancomycin in anIn VitroPharmacokinetic/Pharmacodynamic Model

2015 ◽  
Vol 59 (8) ◽  
pp. 4497-4503 ◽  
Author(s):  
Katie E. Barber ◽  
Jordan R. Smith ◽  
Cortney E. Ireland ◽  
Blaise R. Boles ◽  
Warren E. Rose ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Medical Device ◽  
Bloodstream Infections ◽  
Methicillin Resistant ◽  
Content Type ◽  
Elimination Half ◽  
Antimicrobial Protection ◽  
Mrsa Strains ◽  
Post Hoc

ABSTRACTAnnually, medical device infections are associated with >250,000 catheter-associated bloodstream infections (CLABSI), with up to 25% mortality.Staphylococcus aureus, a primary pathogen in these infections, is capable of biofilm production, allowing organism persistence in harsh environments, offering antimicrobial protection. With increases inS. aureusisolates with reduced susceptibility to current agents, ceftaroline (CPT) offers a therapeutic alternative. Therefore, we evaluated whether CPT would have a role against biofilm-producing methicillin-resistantS. aureus(MRSA), including those with decreased susceptibilities to alternative agents. In this study, we investigated CPT activity alone or combined with daptomycin (DAP) or rifampin (RIF) against 3 clinical biofilm-producing MRSA strains in anin vitrobiofilm pharmacokinetic/pharmacodynamic (PK/PD) model. Simulated antimicrobial regimens were as follows: 600 mg of CPT every 8 h (q8h) (free maximum concentration of drug [fCmax], 17.04 mg/liter; elimination half-life [t1/2], 2.66 h), 12 mg/kg of body weight/day of DAP (fCmax, 14.7 mg/liter;t1/2, 8 h), and 450 mg of RIF q12h (fCmax, 3.5 mg/liter;t1/2, 3.4 h), CPT plus DAP, and CPT plus RIF. Samples were obtained and plated to determine colony counts. Differences in log10CFU/cm2were evaluated by analysis of variance with Tukey'spost hoctest. The strains were CPT and vancomycin susceptible and DAP nonsusceptible (DNS). CPT displayed activity throughout the experiment. DAP demonstrated initial activity with regrowth at 24 h in all strains. RIF was comparable to the drug-free control, and little benefit was observed when combined with CPT. CPT plus DAP displayed potent activity, with an average log10CFU/cm2reduction of 3.33 ± 1.01 from baseline. CPT demonstrated activity against biofilm-producing DNS MRSA. CPT plus DAP displayed therapeutic enhancement over monotherapy, providing a potential option for difficult-to-treat medical device infections.

Hepatic metabolism of vitamin D3 in streptozotocin-induced diabetic rat

1980 ◽  
Vol 93 (3) ◽  
pp. 346-350 ◽  
Author(s):  
Sorel Sulimovici ◽  
Martin S. Roginsky
Keyword(s):  
Vitamin D ◽  
Liver Microsomes ◽  
Hepatic Metabolism ◽  
Enzymic Activity ◽  
Diabetic Rat ◽  
Hydroxyvitamin D ◽  
Streptozotocin Induced Diabetes ◽  
25 Hydroxyvitamin D ◽  
Isolated Liver

Abstract. The effect of streptozotocin-induced diabetes on the in vitro conversion of vitamin D3 to 25-hydroxyvitamin D3 (25-OHD3) by isolated liver microsomes from rachitic rats was examined. Enzymic activity was significantly less than that observed in control animals (P< 0.001). Administration of insulin restored activity almost to control values. These findings provide evidence that diabetes in this animal model produces alterations in the metabolism of vitamin D.

NITD-688, a pan-serotype inhibitor of the dengue virus NS4B protein, shows favorable pharmacokinetics and efficacy in preclinical animal models

2021 ◽  
Vol 13 (579) ◽  
pp. eabb2181
Author(s):  
Stephanie A. Moquin ◽  
Oliver Simon ◽  
Ratna Karuna ◽  
Suresh B. Lakshminarayana ◽  
Fumiaki Yokokawa ◽  
...  
Keyword(s):  
Dengue Virus ◽  
Nonstructural Protein ◽  
Antiviral Drug ◽  
Pharmacokinetic Studies ◽  
Resistance Mutations ◽  
Binding Studies ◽  
Log Reduction ◽  
Elimination Half ◽  
Preclinical Animal Models

Dengue virus (DENV) is a mosquito-borne flavivirus that poses a threat to public health, yet no antiviral drug is available. We performed a high-throughput phenotypic screen using the Novartis compound library and identified candidate chemical inhibitors of DENV. This chemical series was optimized to improve properties such as anti-DENV potency and solubility. The lead compound, NITD-688, showed strong potency against all four serotypes of DENV and demonstrated excellent oral efficacy in infected AG129 mice. There was a 1.44-log reduction in viremia when mice were treated orally at 30 milligrams per kilogram twice daily for 3 days starting at the time of infection. NITD-688 treatment also resulted in a 1.16-log reduction in viremia when mice were treated 48 hours after infection. Selection of resistance mutations and binding studies with recombinant proteins indicated that the nonstructural protein 4B is the target of NITD-688. Pharmacokinetic studies in rats and dogs showed a long elimination half-life and good oral bioavailability. Extensive in vitro safety profiling along with exploratory rat and dog toxicology studies showed that NITD-688 was well tolerated after 7-day repeat dosing, demonstrating that NITD-688 may be a promising preclinical candidate for the treatment of dengue.

scholarly journals Predicting Intestinal and Hepatic First-Pass Metabolism of Orally Administered Testosterone Undecanoate

2020 ◽  
Vol 10 (20) ◽  
pp. 7283 ◽  
Author(s):  
Atheer Zgair ◽  
Yousaf Dawood ◽  
Suhaib M. Ibrahem ◽  
Hyun-moon Back ◽  
Leonid Kagan ◽  
...  
Keyword(s):  
Liver Microsomes ◽  
Hepatic Metabolism ◽  
Hydrolysis Time ◽  
Testosterone Undecanoate ◽  
Main Site ◽  
Cell Homogenate ◽  
First Pass Metabolism ◽  
First Pass ◽  
Pass Metabolism

The bioavailability of orally administered drugs could be impacted by intestinal and hepatic first-pass metabolism. Testosterone undecanoate (TU), an orally administered ester prodrug of testosterone, is significantly subjected to first-pass metabolism. However, the individual contribution of intestinal and hepatic first-pass metabolism is not well determined. Therefore, the aim of the current study was to predict the metabolic contribution of each site. The hydrolysis–time profiles of TU incubation in human liver microsomes and Caco-2 cell homogenate were used to predict hepatic and intestinal first-pass metabolism, respectively. The in vitro half-life (t1/2 inv) for the hydrolysis of TU in microsomal mixtures was 28.31 ± 3.51 min. By applying the “well-stirred” model, the fraction of TU that could escape hepatic first-pass metabolism (FH) was predicted as 0.915 ± 0.009. The incubation of TU in Caco-2 cell homogenate yielded t1/2 inv of 109.28 ± 21.42 min, which was applied in a “Q gut” model to estimate the fraction of TU that would escape intestinal first-pass metabolism (FG) as 0.114 ± 0.02. Accordingly, only 11% of the absorbed fraction of TU could escape intestinal metabolism, while 91% can pass through hepatic metabolism. Hence, compared to the liver, the intestinal wall is the main site where TU is significantly metabolised during first-pass effect.

scholarly journals Characterization and pharmacokinetic parameters of recombinant soluble interleukin-4 receptor

Blood ◽  
1991 ◽  
Vol 77 (11) ◽  
pp. 2396-2403 ◽  
Author(s):  
CA Jacobs ◽  
DH Lynch ◽  
ER Roux ◽  
R Miller ◽  
B Davis ◽  
...  
Keyword(s):  
Half Life ◽  
Integral Membrane Protein ◽  
Interleukin 4 ◽  
Soluble Form ◽  
Pharmacokinetic Parameters ◽  
Pharmacokinetic Studies ◽  
Cdna Clones ◽  
Elimination Half ◽  
Interleukin 4 Receptor

Abstract The interleukin-4 receptor (IL-4R) is expressed as a 140-Kd membrane glycoprotein that binds IL-4 with high affinity. Recently, cDNA clones for the murine IL-4R have been isolated. One clone encodes an integral membrane protein, while another encodes a protein in which translation is terminated before the transmembrane region, thus producing a soluble form of the IL-4R (sIL-4R). HeLa cell clones overexpressing sIL-4R were isolated using a novel filter-overlay and 125I-IL-4 ligand binding technique. Quantitative analysis demonstrated that the kinetics and affinity of IL-4 binding to the recombinant sIL-4R were similar to the native membrane-bound IL-4R. As low doses of sIL-4R specifically inhibited IL-4-induced proliferative responses in vitro, sIL-4R biodistribution and elimination parameters were evaluated to assess the pharmacokinetic potential of sIL-4R as a therapeutic agent. Pharmacokinetic studies demonstrated that radiolabeled sIL-4R had a distribution half-life of 9 minutes and an elimination half-life of 2.3 hours following intravenous (IV) administration. When administered by intraperitoneal or subcutaneous (SC) injection, the elimination half- lives were prolonged to 4.2 hours and 6.2 hours, respectively. Although the initial blood level of sIL-4R was reduced if administered by SC injection, the bioavailability was comparable with IV administration. The main sites of sIL-4R elimination were the liver and kidney.

scholarly journals Investigation on the metabolic characteristics of isobavachin in Psoralea corylifolia L. (Bu-gu-zhi) and its potential inhibition against human cytochrome P450s and UDP-glucuronosyltransferases

2020 ◽  
Author(s):  
Han Xing ◽  
Jing Yang ◽  
Kaidi Ren ◽  
Zifei Qin ◽  
Peile Wang ◽  
...  
Keyword(s):  
Correlation Analysis ◽  
Kinetic Modelling ◽  
Liver Microsomes ◽  
Hepatic Metabolism ◽  
Relative Activity ◽  
Metabolic Characteristics ◽  
Activity Factor ◽  
Human Cytochrome

Abstract Objectives Isobavachin is a phenolic with anti-osteoporosis activity. This study aimed to explore its metabolic fates in vivo and in vitro, and to investigate the potential drug–drug interactions involving CYPs and UGTs. Methods Metabolites of isobavachin in mice were first identified and characterized. Oxidation and glucuronidation study were performed using liver and intestine microsomes. Reaction phenotyping, activity correlation analysis and relative activity factor approaches were employed to identify the main CYPs and UGTs involved in isobavachin metabolism. Through kinetic modelling, inhibition mechanisms towards CYPs and UGTs were also explored. Key findings Two glucuronides (G1 - G2) and three oxidated metabolites (M1 - M3) were identified in mice. Additionally, isobavachin underwent efficient oxidation and glucuronidation by human liver microsomes and HIM with CLint values from 5.53 to 148.79 μl/min per mg. CYP1A2, 2C19 contributed 11.3% and 17.1% to hepatic metabolism of isobavachin, respectively, with CLint values from 8.75 to 77.33 μl/min per mg. UGT1As displayed CLint values from 10.73 to 202.62 μl/min per mg for glucuronidation. Besides, significant correlation analysis also proved that CYP1A2, 2C19 and UGT1A1, 1A9 were main contributors for the metabolism of isobavachin. Furthermore, mice may be the appropriate animal model for predicting its metabolism in human. Moreover, isobavachin exhibited broad inhibition against CYP2B6, 2C9, 2C19, UGT1A1, 1A9, 2B7 with Ki values from 0.05 to 3.05 μm. Conclusions CYP1A2, 2C19 and UGT1As play an important role in isobavachin metabolism. Isobavachin demonstrated broad-spectrum inhibition of CYPs and UGTs.

Assessment of Inhibition of Bovine Hepatic Cytochrome P450 by 43 Commercial Bovine Medicines Using a Combination of In Vitro Assays and Pharmacokinetic Data from the Literature

2020 ◽  
Vol 13 (2) ◽  
pp. 123-131
Author(s):  
Steven X. Hu ◽  
Chase A. Mazur ◽  
Kenneth L. Feenstra
Keyword(s):  
Liver Microsomes ◽  
In Vitro Assay ◽  
In Vitro Assays ◽  
Pharmacokinetic Studies ◽  
Pharmacokinetic Data ◽  
Vitro Assay ◽  
Administration Routes ◽  
Ic50 Values

Background: There has been a lack of information about the inhibition of bovine medicines on bovine hepatic CYP450 at their commercial doses and dosing routes. Objective: The aim of this work was to assess the inhibition of 43 bovine medicines on bovine hepatic CYP450 using a combination of in vitro assay and Cmax values from pharmacokinetic studies with their commercial doses and dosing routes in the literature. Methods: Those drugs were first evaluated through a single point inhibitory assay at 3 μM in bovine liver microsomes for six specific CYP450 metabolisms, phenacetin o-deethylation, coumarin 7- hydroxylation, tolbutamide 4-hydroxylation, bufuralol 1-hydroxylation, chlorzoxazone 6-hydroxylation and midazolam 1’-hydroxylation. When the inhibition was greater than 20% in the assay, IC50 values were then determined. The potential in vivo bovine hepatic CYP450 inhibition by those drugs was assessed using a combination of the IC50 values and in vivo Cmax values from pharmacokinetic studies at their commercial doses and administration routes in the literature. Results: Fifteen bovine medicines or metabolites showed in vitro inhibition on one or more bovine hepatic CYP450 metabolisms with different IC50 values. Desfuroylceftiour (active metabolite of ceftiofur), nitroxinil and flunixin have the potential to inhibit one of the bovine hepatic CYP450 isoforms in vivo at their commercial doses and administration routes. The rest of the bovine medicines had low risks of in vivo bovine hepatic CYP450 inhibition. Conclusion: This combination of in vitro assay and in vivo Cmax data provides a good approach to assess the inhibition of bovine medicines on bovine hepatic CYP450.

scholarly journals PHARMACOKINETIC STUDIES OF A CHRONOTHERAPEUTIC DRUG DELIVERY SYSTEM OF LORNOXICAM BY LC-MS/MS METHOD

2018 ◽  
Vol 10 (6) ◽  
pp. 88
Author(s):  
Sindhu Abraham ◽  
Rajamanickam Deveswaran ◽  
Jayaraman Anbu ◽  
Sharon Furtado ◽  
Bharath Srinivasan
Keyword(s):  
Drug Delivery ◽  
Drug Release ◽  
Maximum Concentration ◽  
Area Under The Curve ◽  
Immediate Release ◽  
Pharmacokinetic Parameters ◽  
Pharmacokinetic Studies ◽  
Elimination Half ◽  
Coated Tablet ◽  
Liquid Chromatography Tandem Mass

Objective: The objective of this study was to investigate differences in pharmacokinetic patterns of immediate release tablet (IR) and compression coated tablet (CCT) of lornoxicam, proposed for the chronotherapeutic treatment of rheumatoid arthritis.Methods: The dosage forms were administered to two groups of white New Zealand rabbits (n=3), and the plasma drug levels were measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Pharmacokinetic parameters like maximum concentration (Cmax), time is taken to reach maximum concentration (Tmax), area under the curve (AUC), elimination half-life (t1/2) and Mean Residence Time (MRT) were determined.Results: In the case of IR tablets, the drug was detected within 15 min after oral administration and a Cmax of 1269.57±4.04 ng/ml were attained at 2±0.15 h. With CCT, the drug was detected only after 5 h and a Cmax of 1279.24±12.76 ng/ml were attained at 8±0.10 h. The CCT showed maximum drug release at the eighth hour in comparison to IR tablet which showed maximum release at the second hour of study.Conclusion: The predominant lag time prior to drug release from CCT is an indication that it is consistent with the requirements of chronopharmaceutical drug delivery. The results suggest that the compression coated tablet is a promising approach for chronotherapeutic management of rheumatoid arthritis.

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