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Visser M.R.,University of Groningen | Baert L.,Chemical Pharm Development | Klooster G.v.'.,Preclinical Development | Schueller L.,Chemical Pharm Development | And 7 more authors.
European Journal of Pharmaceutics and Biopharmaceutics | Year: 2010

TMC240 is a very poorly soluble and poorly permeating HIV protease inhibitor. In order to enhance its oral bioavailability, a fast dissolving inulin-based solid dispersion tablet was developed. During the dissolution test in water (0.5% or 1.0% SLS), this tablet released at least 80% of TMC240 within 30 min, while a tablet with the same composition, but manufactured as physical mixture, released only 6% after 2 h. In a subsequent single-dose study in dogs (200 mg of TMC240), plasma concentrations of TMC240 remained below the lower limit of quantification (<1.00 ng/mL) in all animals (n = 3 per tested formulation), except in one dog receiving the inulin solid dispersion tablet (Cmax = 1.8 ng/mL, AUC0-7 h = 3.0 ng h/mL). In the latter treatment group, ritonavir co-administration (10 mg/kg b.i.d.) increased TMC240 exposure more than 30-fold (mean AUC0-7 h = 108 ng h/mL; Frel = 3588%). Exposure was also 16-fold higher than after TMC240 administration as PEG400 suspension in the presence of ritonavir (AUC0-7 h = 6.7 ng h/mL). The current data demonstrate that a solid dispersion of TMC240 in an inulin matrix allows considerable improvement in the release of poorly water-soluble TMC240, both in vitro in the presence of a surfactant and in vivo upon oral administration. © 2009 Elsevier B.V. All rights reserved. Source

Le Bars G.,Preclinical Development | Dion S.,Preclinical Development | Gauthier B.,Preclinical Development | Mhedhbi S.,Preclinical Development | And 4 more authors.
Regulatory Toxicology and Pharmacology | Year: 2015

Miglyol 812®, a mixture of medium-chain triglycerides, has been identified as an oral vehicle that could improve the solubility and possibly the bioavailability of orally administered drugs during the non-clinical safety assessment. The toxicity of Miglyol was assessed in Göttingen® minipigs upon daily oral administration (gavage) for six weeks, at dosing-volumes of 0.5 and 2 mL/kg/day, compared to controls receiving 0.5% CarboxyMethylCellulose/0.1% Tween® 80 in water at 2 mL/kg/day. The control vehicle did not induce any findings. Miglyol at 0.5 and 2 mL/kg/day induced transient tremors, abnormal color of feces and increase in triglycerides. Miglyol at 2 ml/kg/day also induced reduced motor activity, decreased food intake, respiratory signs (2/6 animals) and increased total and LDL-cholesterol. At necropsy, the lung of 3/6 animals treated at 2 mL/kg/day presented abnormal color and/or irregular surface correlated with a chronic bronchiolo-alveolar inflammation. This finding is probably due to aspiration pneumonia in relation to the administration method and the high viscosity of Miglyol. Overall, the oral administration of pure Miglyol 812® for six weeks up to 2 mL/kg was less tolerated than that of the control vehicle. Miglyol as vehicle for sub-chronic oral toxicity studies in minipigs should be used with a limited dosing-volume. © 2015 Elsevier Inc. Source

Losada C.,Preclinical Development | Alberti J.J.,Preclinical Development | Saurina J.,University of Barcelona | Sentellas S.,Preclinical Development
Analytical and Bioanalytical Chemistry | Year: 2012

Recently, liquid chromatography coupled to inductively coupled plasma mass spectrometry (LC-ICP/MS) has been introduced to deal with some applications in the field of pharmaceutical, biomedical, and clinical analysis. In the case of drug research, the number of drugs and their metabolites containing detectable elements is quite limited. In this paper, LC-ICP/MS has been demonstrated to be suitable for the determination of S-containing drugs and their metabolites. In order to minimize the interference of polyatomic oxygen (m/z 32), the indirect detection of S, by means of the SO+ ion (m/z 48), was optimized. For quantification purposes, it has been encountered that the percentage of organic solvent in the mobile phase strongly affects the sensitivity. Here, corrective strategies based on calibration curves established at different solvent concentrations (solvent-zone quantification) and post-column gradient compensation have been proposed to circumvent sensitivity variations. Results obtained have shown that suitable calibration models have been built for any compound regardless of the solvent percentage at which it is eluted from the chromatographic column. To prove the applicability of this methodology, the metabolism of ethacrynic acid and tiotropium bromide has been studied in vitro and in vivo. In the first case, ethacrynic acid does not contain S in its structure, however, the major route of metabolism for this compound consists of the formation of glutathione adduct and its further degradation. In the second case, tiotropium bromide contains two S atoms in its structure. © Springer-Verlag 2012. Source

Hayes G.M.,Preclinical Development | Cairns B.,Preclinical Development | Levashova Z.,Preclinical Development | Chinn L.,Preclinical Development | And 7 more authors.
American Journal of Translational Research | Year: 2015

Soft tissue sarcoma (STS) is a heterogenous tumor arising from the embryonic mesoderm represented by approximately 50 histological subtypes. Effective therapeutic intervention is lacking for recurrent, late stage and metastatic disease. CD39, a cell-surface ectonucleotidase, has previously been shown to be upregulated in hematological malignancies and various epithelial tumors, but not in STS. Here, we show by mass spectrometry and immunohistochemistry that CD39 is highly expressed in primary patient sarcoma samples. Moreover, CD39 nucleotidase activity is enhanced in fibrosarcoma compared with normal control cells. We demonstrate that an inhibitory monoclonal anti-CD39 antibody, abrogates CD39 enzymatic activity significantly and prolongs survival in a lethal metastatic patient-derived sarcoma model. Taken together, the data suggest CD39 is a novel therapeutic target for the treatment of STS. © 2015 E-Century Publishing Corporation. All rights reserved. Source

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