Frontage Laboratories Inc.
Frontage Laboratories Inc.
Nallani G.C.,701 PrincetonSouth Corporate Center |
ElNaggar S.F.,701 PrincetonSouth Corporate Center |
Shen L.,Frontage Laboratories Inc. |
Chandrasekaran A.,701 PrincetonSouth Corporate Center
Regulatory Toxicology and Pharmacology | Year: 2017
The in vitro comparative animal metabolism study is now a data requirement under EU Directive 1107/2009 for registration of plant protection products. This type of study helps determine the extent of metabolism of a chemical in each surrogate species and whether any unique human metabolite(s) are formed. In the present study, metabolism of racemic [14C]-benalaxyl, a fungicide was investigated in cryopreserved rat, dog and human hepatocytes. The metabolites generated were identified/characterized by LC/MS/MS with radiometric detection and comparison with reference standards. [14C]-glucuronide conjugates of benalaxyl metabolites in rat, dog and human hepatocytes were confirmed via additional experiments in which known reference standards were incubated with dog liver microsomes in the presence of UDPGA. After 4 h of incubation, benalaxyl was extensively metabolized in all the species with the following trend: dog (100%) > human (86%) > rat (75%). In all species, the major metabolic pathways consisted of hydroxylation of the methyl group in the xylene moiety to 2-hydroxymethyl-benalaxyl, further oxidation to its carboxylic acid analogue (benalaxyl-2-benzoic acid), and hydrolysis of the methyl ester to yield benalaxyl acid or 2-hydroxymethyl benalaxyl acid. In addition, glucuronidation of phase I metabolites occurred in all species, to a higher extent in dog hepatocytes in which 2-hydroxymethyl-benalaxyl-glucuronide conjugate constituted the most significant metabolite. No major unique metabolite was observed in human hepatocytes. Also, benalaxyl did not undergo stereo-selective metabolism in rat or human hepatocytes. © 2016 Elsevier Inc.
Ma Y.,Scripps Research Institute |
Mcclatchy D.B.,Scripps Research Institute |
Barkallah S.,Frontage Laboratories Inc. |
Wood W.W.,Frontage Laboratories Inc. |
Yates J.R.,Scripps Research Institute
Journal of Proteome Research | Year: 2017
Here we describe a new strategy, HILAQ (Heavy Isotope Labeled Azidohomoalanine Quantification), to rapidly quantify the molecular vulnerability profile to oxytosis, which is an oxidative stress-induced programed cell death pathway that has been reported to be involved in aging and neurodegenerative diseases. HILAQ was able to quantify 1962 newly synthesized proteins (NSPs) after 1 h of pulse labeling in HEK293T cell line, while 353 proteins were quantified using the previously published QuaNCAT protocol. HILAQ was successfully applied to the HT22 oxytosis model. 226 proteins were found to have a two-fold change in abundance, and 108 proteins were enriched in the cell death pathway, demonstrating the utility of HT22 cells as a tool to study the molecular details of cell death involved in neurodegenerative diseases. The HILAQ strategy simplifies the analysis of newly synthesized proteomes through the use of isobaric labels and achieves higher sensitivity than previously published methods. © 2017 American Chemical Society.
Shah A.K.,Aurolife Pharma LLC |
Agnihotri S.A.,Frontage Laboratories Inc.
Journal of Controlled Release | Year: 2011
Preclinical profiling for a New Chemical Entity (NCE), if carried out carefully, can be a good predictor of human clinical outcome. Along with the pre-clinical study design a thorough understanding of the physico-chemical properties of the drug candidate and a careful selection of the formulation development strategy are of high importance. The study scientist can experience various challenges in executing a pre-clinical study. This review article provides an overview of the significance of pre-formulation study parameters and their relevance to preclinical studies. Various physico-chemical properties such as solubility, partition co-efficient, and permeability are attributes critical to the performance of the drug substance. This article presents unique formulation development strategies for the successful completion of pre-clinical studies. Formulation development approach for a pre-clinical study involves taking into consideration various important factors such as duration of the study, Biopharmaceutics Classification System (BCS) of the drug, intended duration of action and the desired route of administration. These parameters play key role in the selection of solubilizers, surfactants, co-solvents and optimum pH for the formulation. Two most common routes of administration in the early screening of pharmaceuticals viz., oral and intravenous are emphasized. The article also describes recent advances in preclinical formulation development including selected examples of in vivo preclinical models for anti-cancer, anti-viral, anti-diabetic and anti-hypertensive drugs. Adherence to the regulatory requirement is also the key to successful completion of the preclinical development. An overview of preclinical formulation development along with basic concepts and the recent studies conducted in the past decade are presented in this review. © 2011 Elsevier B.V. All rights reserved.
Liu W.,Jinan University |
Kulkarni K.,Frontage Laboratories Inc. |
Hu M.,University of Houston
Expert Opinion on Drug Metabolism and Toxicology | Year: 2013
Introduction: Gender differences have a significant impact on absorption, disposition and overall systemic bioavailability of various xenobiotics in rodents as well as humans. Over the past few years, significant research has explored and investigated the effects of gender differences on the expression profiles of uridine 5'-diphospho-glucuronosyltransferases (or UGTs) in rodents but no data is available that could effectively help predict the metabolic clearance or systemic bioavailability of xenobiotics predominantly metabolized by UGT enzymes in vivo. Areas covered: This review highlights and explains the unique features of the metabolic clearance reactions catalyzed by UGTs (metabolite formation) and its intricate interactions with the efflux transporters that will transport hydrophilic glucuronides out of cell in vivo. In addition, the article reviews the gender differences in hepatic and extrahepatic UGT isoforms and efflux transporter expression profiles in rodents. Furthermore, the article highlights the implications of sex hormone differences on metabolic clearance and thereby oral bioavailability of xenobiotics that are predominantly metabolized by UGTs in vivo. Finally, the article reviews the impact of plasma sex hormone level differences on UGT enzyme and efflux transporter expression profiles using in situ and in vivo models. Expert opinion: The authors believe that the article demonstrates that gender, and perhaps more importantly the differences in plasma sex hormone levels in female species, will drive the gender-dependent differences in expression profiles of UGT enzymes and efflux transporters. These differences significantly affect the metabolic clearance and the systemic bioavailability of compounds eliminated via this disposition pathway. © 2013 Informa UK, Ltd.
Huang M.-Q.,Janssen Pharmaceutical |
Lin Z.,Frontage Laboratories Inc. |
Weng N.,Janssen Pharmaceutical
Bioanalysis | Year: 2013
High-resolution MS (HRMS) in conjunction with LC (LC-HRMS) has become available to many laboratories in the pharmaceutical industry. Due to its enhanced, though sometime perceived, specificity using the high-resolution power and its capability of simultaneous quantitation and structural elucidation using the post-acquisition data mining feature, utilization of LC-HRMS for bioanalysis could lead to potential rapid and reliable method development as well as sample analysis, thus generating both cost and resource savings. Here, we would like to share our perspectives about several current and future applications of LC-HRMS in bioanalysis. We will also discuss the factors influencing the quality of method establishment and potential pitfalls that need to be considered for the utilization of LC-HRMS in the field of regulated bioanalysis. We believe when utilized appropriately, LC-HRMS will play a significant role in the future landscape of quantitative bioanalysis. © 2013 Future Science Ltd.
O'Shannessy D.J.,Morphotek Inc. |
Somers E.B.,Morphotek Inc. |
Palmer L.M.,Morphotek Inc. |
Thiel R.P.,Thiel Statistical Consultants |
And 3 more authors.
Journal of Ovarian Research | Year: 2013
Background: Evaluate and compare the utility of serum folate receptor alpha (FRA) and megakaryocyte potentiating factor (MPF) determinations relative to serum CA125, mesothelin (MSLN) and HE4 for the diagnosis of epithelial ovarian cancer (EOC). Methods. Electrochemiluminescent assays were developed for FRA, MSLN and MPF and used to assess the levels of these biomarkers in 258 serum samples from ovarian cancer patients. Commercial assays for CA125 and HE4 were run on a subset of 176 of these samples representing the serous histology. Data was analyzed by histotype, stage and grade of disease. A comparison of the levels of the FRA, MSLN and MPF biomarkers in serum, plasma and urine was also performed in a subset of 57 patients. Results: Serum and plasma levels of FRA, MSLN and MPF were shown to be highly correlated between the two matrices. Correlations between all pairs of markers in 318 serum samples were calculated and demonstrated the highest correlation between HE4 and MPF, and the lowest between FRA and MPF. Serum levels of all markers showed a dependence on both stage and grade of disease. A multi-marker logistic regression model was developed resulting in an AUC=0.91 for diagnosis of serous ovarian cancer, a significant improvement over the AUC for any of the individual markers, including CA125 (AUC=0.84). Conclusions: FRA has significant potential as a biomarker for ovarian cancer, both as a stand-alone marker and in combination with other known markers for EOC. The lack of correlation between the various markers analyzed in the present study suggests that a panel of markers can aid in the detection and/or monitoring of this disease. © 2013 O'Shannessy et al.; licensee BioMed Central Ltd.
Zhang W.,Frontage Laboratories Inc. |
Han F.,Frontage Laboratories Inc. |
Zhao H.,Frontage Laboratories Inc. |
Lin Z.J.,Frontage Laboratories Inc. |
And 2 more authors.
Biomedical Chromatography | Year: 2012
Metformin is a well-known oral antihyperglycemic drug used in treatment of type II diabetes. Analysis of metformin in biological fluids is a challenge owing to its high polarity and small molecular size, which lead to poor retention of metformin on reversed-phase liquid chromatographic columns. A high-throughput method was developed and validated for the determination of metformin in rat plasma in support of preclinical toxicology studies, using hydrophilic interaction liquid chromatography tandem mass spectrometry (HILIC-MS/MS) and Tecan automated sample preparation. Extracted samples were directly injected onto the unbounded silica column with an aqueous-organic mobile phase. This HILIC-MS/MS method was validated for accuracy, precision, sensitivity, stability, matrix effect, recovery and calibration range. Acceptable intra-run and inter-run assay precision (coefficient of variation≤3.9%) and accuracy (99.0-101.8%) were achieved over a linear range of 50-50,000ng/mL. Metformin is stable in rat plasma for at least 6h at room temperature, 147days at -70°C and through three freeze (-70°C) and thaw cycles. Metformin is also stable in rat whole blood for at least 2h at room temperature and in an ice-water bath. The validated method was successfully used in support of several preclinical studies where metformin is dosed together with an investigational drug substance. The ruggedness of the validated method was demonstrated by the incurred sample reproducibility test. Copyright © 2011 John Wiley & Sons, Ltd.
Modak A.S.,Frontage Laboratories Inc.
Journal of Breath Research | Year: 2011
Over the last decade noninvasive diagnostic phenotype [13C]- breath tests using suitably labeled 13C substrates as well as breath tests using endogenous/exogenous volatile organic compounds in breath have been extensively researched. Despite the potential benefits of these companion diagnostic tests and stand-alone diagnostic tests for patient/disease stratification and market segmentation to personalize medicine, the clinical and commercial development of these diagnostic tests will need to overcome a number of regulatory, financial and scientific hurdles prior to their acceptance into routine clinical practice. © 2011 IOP Publishing Ltd.
Lin Z.J.,Frontage Laboratories Inc. |
Li W.,Novartis |
Weng N.,Johnson and Johnson Pharmaceutical Research and Development LLC
Bioanalysis | Year: 2011
With the globalization of drug development activities, transferring a validated bioanalytical procedure to a different site within a pharmaceutical company, or to one or multiple contract research organizations has been dramatically increased in recent years. Undeniably, bioanalytical method transfer is the needed step prior to routine sample analysis at the receiving laboratory. It is clearly stated in the 2001 US FDA Guidance on Bioanalytical Method Validation that a partial validation is needed for method transfer between laboratories. In the current EMA draft guidelines on method validation, the necessity of a method transfer is also emphasized. However, the above guidelines do not give many details on how and when a method transfer validation should be conducted. There is a need for a step-by-step deliberation on the overall strategies, procedures and even technical details for a successful bioanalytical method transfer. In this article, we review the contemporary information available in the scientific literature on method transfer and illustrate various bioanalytical method transfer scenarios using case studies. A flexible and fit-for-purpose bioanalytical method transfer strategy is proposed. © 2011 Future Science Ltd.
Modak A.S.,Frontage Laboratories Inc.
Journal of Breath Research | Year: 2013
Over the last decade non invasive diagnostic phenotype [ 13C]-breath tests as well as tests using endogenous volatile organic compounds (VOCs) in breath have been researched extensively. However, only three breath tests have been approved by the FDA over the last 15 years. Despite the potential benefits of these companion diagnostic tests (CDx) for evaluation of drug metabolizing enzyme activities and standalone diagnostic tests for disease diagnosis to personalize medicine, the clinical and commercial development of breath tests will need to overcome a number of regulatory, financial and scientific hurdles prior to their acceptance into routine clinical practice. The regulatory agencies (FDA and EMEA) need to adapt and harmonize their approval process for companion diagnostic tests as well as standalone diagnostic breath tests for personalized medicine. The Center for Devices and Radiological Health has deemed any breath test that involves a labeled 13C substrate/drug and a device requires a Pre Market Approval (PMA), which is analogous to an approved New Drug Application. A PMA is in effect, a private license granted to the applicant for marketing a particular medical device. Any breath test with endogenous VOCs along with a device can be approved via the 510(k) application. A number of 13C breath tests with clinical applications have been researched recently and results have been published in reputed journals. Diagnostic companies will need to invest the necessary financial resources to develop and get regulatory approval for diagnostic breath tests capable of identifying responders/non responders for FDA approved drugs with narrow therapeutic indices (personalized medicine) or for evaluating the activity of drug metabolizing P450 polymorphic enzymes or for diagnosing diseases at an early stage or for monitoring the efficacy of medications. The financial success of these diagnostic breath tests will then depend entirely on how the test is marketed to physicians, healthcare organizations, payers (reimbursement), insurance companies and most importantly to patients, the eventual beneficiaries. © 2013 IOP Publishing Ltd.