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Nottingham, United Kingdom

Choy G.,Astex | Joshi-Hangal R.,Astex | Oganesian A.,Astex | Fine G.,Astex | And 6 more authors.
Cancer Chemotherapy and Pharmacology | Year: 2012

Purpose: Amuvatinib is a multi-targeted tyrosine kinase inhibitor with activity that also disrupts DNA damage repair through suppression of homologous recombination protein Rad51. Amuvatinib dry-powder capsules (DPC) showed evidence of activity in early Phase 1 cancer studies but low systemic exposure. The purposes of the studies were to investigate the cause of low exposure, develop, and test an alternative formulation with improved exposure, and establish the dose to be tested in future studies in cancer patients. Methods: Three studies were conducted in a total of 58 healthy subjects: a food-effect study using amuvatinib DPC, a single-dose pharmacokinetic study comparing amuvatinib DPC to a new lipid-suspension capsules (LSC), and a multiple-dose pharmacokinetic study using amuvatinib LSC. Results: A high-fat meal administered with amuvatinib DPC increased the rate and extent of absorption compared to the Fasted state, a 183 and 118% increase in the mean C max and AUC 0-∞ of amuvatinib, respectively. The single-dose pharmacokinetics of amuvatinib LSC resulted in an approximately two-third-fold increased exposure (AUC) compared with amuvatinib DPC. The multiple-dose pharmacokinetics of the amuvatinib LSC 300 mg administered every 8 h exhibited improved accumulation compared with the 12-h regimens and achieved presumed therapeutic level safely with no serious or severe adverse events reported. No subject discontinued treatment due to an adverse event. Conclusion: Amuvatinib LSC, 300 mg every 8 h, is being studied in cancer patients based on the improved exposure and similar safety profile to amuvatinib DPC. A lipid-based formulation approach may be a useful tool for other low aqueous soluble compounds. © 2012 Springer-Verlag. Source

Nakamaru Y.,Mitsubishi Group | Hayashi Y.,Mitsubishi Group | Ikegawa R.,Mitsubishi Group | Kinoshita S.,Mitsubishi Group | And 8 more authors.
Xenobiotica | Year: 2014

1. The absorption, metabolism and excretion of teneligliptin were investigated in healthy male subjects after a single oral dose of 20mg [ 14C]teneligliptin. 2. Total plasma radioactivity reached the peak concentration at 1.33h after administration and thereafter disappeared in a biphasic manner. By 216h after administration, 90% of the administered radioactivity was excreted, and the cumulative excretion in the urine and faeces was 45.4% and 46.5%, respectively. 3. The most abundant metabolite in plasma was a thiazolidine-1-oxide derivative (designated as M1), which accounted for 14.7% of the plasma AUC (area under the plasma concentration versus time curve) of the total radioactivity. The major components excreted in urine were teneligliptin and M1, accounting for 14.8% and 17.7% of the dose, respectively, by 120h, whereas in faeces, teneligliptin was the major component (26.1% of the dose), followed by M1 (4.0%). 4. CYP3A4 and FMO3 are the major enzymes responsible for the metabolism of teneligliptin in humans. 5. This study indicates the involvement of renal excretion and multiple metabolic pathways in the elimination of teneligliptin from the human body. Teneligliptin is unlikely to cause conspicuous drug interactions or changes in its pharmacokinetics patients with renal or hepatic impairment, due to a balance in the elimination pathways. © 2014 Informa UK Ltd. Source

Vishwanathan K.,Astrazeneca | Mair S.,Quotient Clinical Ltd. | Gupta A.,Astrazeneca | Atherton J.,Astrazeneca | And 3 more authors.
Drug Metabolism and Disposition | Year: 2014

Avibactam, a novel non-b-lactam b-lactamase inhibitor with activity against Ambler class A, class C, and some class D enzymes is being evaluated in combination with various β-lactam antibiotics to treat serious bacterial infections. The in vivo mass balance recovery and metabolite profile of [14C] avibactam (500 mg/1-h infusion) was assessed in six healthy male subjects, and a series of in vitro experiments evaluated the metabolism and drug-drug interaction potential of avibactam. In the mass balance study, measurement of plasma avibactam (using a validated liquid chromatography-tandem mass spectrometry method) and total radioactivity in plasma, whole blood, urine, and feces (using liquid scintillation counting) indicated that most of the avibactam was excreted unchanged in urine within 12 hours, with recovery complete (>97% of the administered dose) within 96 hours. Geometric mean avibactam renal clearance (158 ml/min) was greater than the product of unbound fraction of drug and glomerular filtration rate (109.5 ml/min), suggesting that active tubular secretion accounted for some renal elimination. There was no evidence of metabolism in plasma and urine, with unchanged avibactam the major component in both matrices. Avibactam demonstrated in vitro substrate potential for organic anion transporters 1 and 3 (OAT1 and OAT3) proteins expressed in human embryonic kidney 293 cells (Km > 1000 mM; >10-fold the Cmax of a therapeutic dose), which could account for the active tubular secretion observed in vivo. Avibactam uptake by OAT1 and OAT3 was inhibited by probenecid, a potent OAT1/OAT3 inhibitor. Avibactam did not interact with various other membrane transport proteins or cytochrome P450 enzymes in vitro, suggesting it has limited propensity for drug-drug interactions involving cytochrome P450 enzymes. © 2014 by The American Society for Pharmacology and Experimental Therapeutics. Source

Emanuel I.A.,San Francisco State University | Blaiss M.S.,Allergy and Asthma Care | Meltzer E.O.,Allergy and Asthma Medical Group and Research Center | Evans P.,Quotient Clinical Ltd. | Connor A.,Quotient Clinical Ltd.
American Journal of Rhinology and Allergy | Year: 2014

Background: Sensory attributes of intranasal corticosteroids, such as rundown to the back of the throat, may influence patient treatment preferences. This study compares the nasal deposition and nasal retention of a radiolabeled solution of ciclesonide nasal aerosol (CIC-hydrofluoroalkane [HFA]) with a radiolabeled suspension of mometasone furoate monohydrate aqueous nasal spray (MFNS) in subjects with either perennial allergic rhinitis (AR) or seasonal AR. Methods: In this open-label, single-dose, randomized, crossover scintigraphy study, 14 subjects with symptomatic AR received a single dose of radiolabeled 74-μg CIC-HFA (37 μg/spray, 1 spray/each nostril) via a nasal metered-dose inhaler or a single dose of radiolabeled 200-μg MFNS (50 μg/spray, 2 sprays/each nostril), with a minimum 5-day washout period between treatments. Initial deposition (2 minutes postdose) of radiolabeled CIC-HFA and MFNS in the nasal cavity, nasopharynx, and on nasal wipes, and retention of radioactivity in the nasal cavity and nasal run-out on nasal wipes at 2, 4, 6, 8, and 10 minutes postdose were quantified with scintigraphy. Results: At 2 and 10 minutes postdose, deposition of radiolabeled CIC-HFA was significantly higher in the nasal cavity versus radiolabeled MFNS (99.42% versus 86.50% at 2 minutes, p = 0.0046; and 81.10% versus 54.31% at 10 minutes, p < 0.0001, respectively; p values unadjusted for multiplicity). Deposition of radioactivity on nasal wipes was significantly higher with MFNS versus CIC-HFA at all five time points, and posterior losses of radiolabeled formulation were significantly higher with MFNS at 6, 8, and 10 minutes postdose. Conclusion: In this scintigraphic study, significantly higher nasal deposition and retention of radiolabeled aerosol CIC-HFA were observed versus radiolabeled aqueous MFNS in subjects with AR. Copyright © 2014, OceanSide Publications, Inc. Source

Benito-Gallo P.,University of Nottingham | Franceschetto A.,University of Nottingham | Franceschetto A.,University of Padua | Wong J.C.M.,University of Nottingham | And 4 more authors.
European Journal of Pharmaceutics and Biopharmaceutics | Year: 2015

Triglycerides (TG) are one of the most common excipients used in oral lipid-based formulations. The chain length of the TG plays an important role in the oral bioavailability of the co-administered drug. Fatty acid (FA) chain-length specificity of porcine pancreatic lipase was studied by means of an in vitro lipolysis model under bio-relevant conditions at pH 6.80. In order to determine the total extent of lipolysis, back-titration experiments at pH 11.50 were performed. Results suggest that there is a specific chain length range (C2-C8) for which pancreatic lipase shows higher activity. This specificity could result from a combination of physicochemical properties of TGs, 2-monoglycerides (2-MGs) and FAs, namely the droplet size of the TGs, the solubility of 2-MGs within mixed micelles, and the relative stability of the FAs as leaving groups in the hydrolysis reaction. During experimentation, it was evident that an optimisation of lipolysis conditions was needed for tighter control over pH levels so as to better mimic in vivo conditions. 1 M NaOH, 3.5 mL/min maximum dosing rate, and 3 μL/min minimum dosing rate were the optimised set of conditions that allowed better pH control, as well as the differentiation of the lipolysis of different lipid loads. © 2015 Elsevier B.V. All rights reserved. Source

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