Showing papers by "Vertex Pharmaceuticals published in 2017"
TL;DR: CFTR modulator therapy with tezacaftor–ivacaftor or ivacaftors alone was efficacious in patients with cystic fibrosis who were heterozygous for the Phe508del deletion and a CFTR residual‐function mutation.
Abstract: Vertex Pharmaceuticals; NIHR Respiratory Disease Biomedical Research Unit at the Royal Brompton and Harefield NHS Foundation Trust; Imperial College London; Cystic Fibrosis Foundation Therapeutics Development Network; National Institutes of Health [P30DK072482, R35HL135816, U54TR001005]
377 citations
TL;DR: Patients, all site personnel including the investigator and the site monitor, and the study team were blinded, with the exception of site personnel needing this information in the event of medical emergency or pregnancy and patient safety and regulatory affairs personnel to meet serious adverse event reporting requirements.
243 citations
TL;DR: The annualised rate of ppFEV1 decline was reduced in lumacaftor/ivacaftar-treated patients compared with matched controls, and the estimated annual rate of decline in percent predicted FEV1 in treated patients was compared with that of a matched registry cohort.
231 citations
TL;DR: It is demonstrated BVD-523 holds promise as a treatment for ERK-dependent cancers, including those whose tumors have acquired resistance to other treatments targeting upstream nodes of the MAPK pathway.
Abstract: Aberrant activation of signaling through the RAS-RAF-MEK-ERK (MAPK) pathway is implicated in numerous cancers, making it an attractive therapeutic target. Although BRAF and MEK-targeted combination therapy has demonstrated significant benefit beyond single-agent options, the majority of patients develop resistance and disease progression after approximately 12 months. Reactivation of ERK signaling is a common driver of resistance in this setting. Here we report the discovery of BVD-523 (ulixertinib), a novel, reversible, ATP-competitive ERK1/2 inhibitor with high potency and ERK1/2 selectivity. In vitro BVD-523 treatment resulted in reduced proliferation and enhanced caspase activity in sensitive cells. Interestingly, BVD-523 inhibited phosphorylation of target substrates despite increased phosphorylation of ERK1/2. In in vivo xenograft studies, BVD-523 showed dose-dependent growth inhibition and tumor regression. BVD-523 yielded synergistic antiproliferative effects in a BRAFV600E-mutant melanoma cell line xenograft model when used in combination with BRAF inhibition. Antitumor activity was also demonstrated in in vitro and in vivo models of acquired resistance to single-agent and combination BRAF/MEK-targeted therapy. On the basis of these promising results, these studies demonstrate BVD-523 holds promise as a treatment for ERK-dependent cancers, including those whose tumors have acquired resistance to other treatments targeting upstream nodes of the MAPK pathway. Assessment of BVD-523 in clinical trials is underway (NCT01781429, NCT02296242, and NCT02608229). Mol Cancer Ther; 16(11); 2351-63. ©2017 AACR.
152 citations
TL;DR: Improvements in lung clearance index, sweat chloride, nutritional status, and health‐related quality of life were observed after 24 weeks of treatment; the safety profile was generally similar to that observed in larger lumacaftor/ivacaftors trials with older patients.
Abstract: Rationale: Combination lumacaftor/ivacaftor has been shown to improve lung function and other endpoints in patients aged 12 years and older with cystic fibrosis and homozygous for F508del-CFTR, but it has not been assessed in younger patients.Objectives: In this open-label phase III trial, we evaluated the safety, tolerability, pharmacodynamics, and efficacy of lumacaftor/ivacaftor combination therapy in patients aged 6–11 years with cystic fibrosis who were homozygous for F508del-CFTR.Methods: Patients (N = 58) received 200 mg lumacaftor/250 mg ivacaftor orally every 12 hours for 24 weeks in addition to their existing cystic fibrosis medications.Measurements and Main Results: Lumacaftor/ivacaftor was well tolerated; the safety profile was generally similar to that observed in larger lumacaftor/ivacaftor trials with older patients. Four patients discontinued (two because of drug-related adverse events: elevated liver transaminases, n = 1; rash, n = 1). No safety concerns were associated with spirometry. N...
138 citations
TL;DR: Opportunities for chemogenomic screening to considerably expedite the conversion of phenotypic screening projects into target-based drug discovery approaches are described and other applications are explored, including drug repositioning, predictive toxicology and the discovery of novel pharmacological modalities.
Abstract: The allure of phenotypic screening, combined with the industry preference for target-based approaches, has prompted the development of innovative chemical biology technologies that facilitate the identification of new therapeutic targets for accelerated drug discovery. A chemogenomic library is a collection of selective small-molecule pharmacological agents, and a hit from such a set in a phenotypic screen suggests that the annotated target or targets of that pharmacological agent may be involved in perturbing the observable phenotype. In this Review, we describe opportunities for chemogenomic screening to considerably expedite the conversion of phenotypic screening projects into target-based drug discovery approaches. Other applications are explored, including drug repositioning, predictive toxicology and the discovery of novel pharmacological modalities.
134 citations
TL;DR: This work suggests that incipient signaling in T cells initiates global cytoskeletal rearrangements across the whole cell, including a stiffening process for possibly mechanically supporting contact formation at the immunological synapse interface as well as a central ramified transportation network apparently directed at the consolidation of the contact and the delivery of effector functions.
Abstract: T cell activation and especially trafficking of T cell receptor microclusters during immunological synapse formation are widely thought to rely on cytoskeletal remodeling. However, important details on the involvement of actin in the latter transport processes are missing. Using a suite of advanced optical microscopes to analyze resting and activated T cells, we show that, following contact formation with activating surfaces, these cells sequentially rearrange their cortical actin across the entire cell, creating a previously unreported ramifying actin network above the immunological synapse. This network shows all the characteristics of an inward-growing transportation network and its dynamics correlating with T cell receptor rearrangements. This actin reorganization is accompanied by an increase in the nanoscale actin meshwork size and the dynamic adjustment of the turnover times and filament lengths of two differently sized filamentous actin populations, wherein formin-mediated long actin filaments support a very flat and stiff contact at the immunological synapse interface. The initiation of immunological synapse formation, as highlighted by calcium release, requires markedly little contact with activating surfaces and no cytoskeletal rearrangements. Our work suggests that incipient signaling in T cells initiates global cytoskeletal rearrangements across the whole cell, including a stiffening process for possibly mechanically supporting contact formation at the immunological synapse interface as well as a central ramified transportation network apparently directed at the consolidation of the contact and the delivery of effector functions.
132 citations
TL;DR: An overview on the benefits, caveats, and impact of in silico ADME-PK should serve as a resource for medicinal Chemists, computational chemists, and DMPK scientists working in drug design to increase their knowledge in the area.
Abstract: In silico tools to investigate absorption, distribution, metabolism, excretion, and pharmacokinetics (ADME-PK) properties of new chemical entities are an integral part of the current industrial drug discovery paradigm. While many companies are active in the field, scientists engaged in this area do not necessarily share the same background and have limited resources when seeking guidance on how to initiate and maintain an in silico ADME-PK infrastructure in an industrial setting. This work summarizes the views of a group of industrial in silico and experimental ADME scientists, participating in the In Silico ADME Working Group, a subgroup of the International Consortium for Innovation through Quality in Pharmaceutical Development (IQ) Drug Metabolism Leadership Group. This overview on the benefits, caveats, and impact of in silico ADME-PK should serve as a resource for medicinal chemists, computational chemists, and DMPK scientists working in drug design to increase their knowledge in the area.
92 citations
TL;DR: Sweat chloride and respiratory symptom scores improved with lumacaftor/ivacaftors, though no meaningful benefit was seen in ppFEV1 or body mass index in patients heterozygous for F508del‐CFTR.
Abstract: Rationale: In a prior study, lumacaftor/ivacaftor treatment (≤28 d) in patients with cystic fibrosis (CF) heterozygous for F508del-CFTR did not improve lung function.Objectives: To evaluate an optimized lumacaftor/ivacaftor dosing regimen with a longer duration in a cohort of patients heterozygous for F508del-CFTR.Methods: Patients aged 18 years or older with a confirmed CF diagnosis and percent predicted FEV1 (ppFEV1) of 40 to 90 were randomized to lumacaftor/ivacaftor (400 mg/250 mg every 12 h) or placebo daily for 56 days. Primary outcomes were change in ppFEV1 at Day 56 and safety. Other disease markers were evaluated.Measurements and Main Results: Of 126 patients, 119 (94.4%) completed the study. Lumacaftor/ivacaftor was well tolerated, although chest tightness and dyspnea occurred more frequently with active treatment than with placebo (27.4% vs. 14.3% and 14.5% vs. 6.3%, respectively). Mean (SD) ppFEV1 values at baseline were 62.9 (14.3) in the active treatment group and 60.1 (14.0) in the placebo ...
73 citations
TL;DR: Biological properties of LPS-degrading lyase derived from a Pseudomonas phage reveal a potential towards its applications in antimicrobial design and as a microbiological or biotechnological tool.
Abstract: Pseudomonas phage LKA1 of the subfamily Autographivirinae encodes a tailspike protein (LKA1gp49) which binds and cleaves B-band LPS (O-specific antigen, OSA) of Pseudomonas aeruginosa PAO1. The crystal structure of LKA1gp49 catalytic domain consists of a beta-helix, an insertion domain and a C-terminal discoidin-like domain. The putative substrate binding and processing site is located on the face of the beta-helix whereas the C-terminal domain is likely involved in carbohydrates binding. NMR spectroscopy and mass spectrometry analyses of degraded LPS (OSA) fragments show an O5 serotype-specific polysaccharide lyase specificity. LKA1gp49 reduces virulence in an in vivo Galleria mellonella infection model and sensitizes P. aeruginosa to serum complement activity. This enzyme causes biofilm degradation and does not affect the activity of ciprofloxacin and gentamicin. This is the first comprehensive report on LPS-degrading lyase derived from a Pseudomonas phage. Biological properties reveal a potential towards its applications in antimicrobial design and as a microbiological or biotechnological tool.
69 citations
TL;DR: 3He-MRI provides an individual quantification of disease burden that may be able to detect aspects of the disease missed by population-based spirometry metrics, as assessed by human reader and computer algorithm.
TL;DR: Sweat chloride level changes in response to potentiation of the CFTR protein by ivacaftor appear to be a predictive pharmacodynamic biomarker of lung function changes on a population basis but are unsuitable for the prediction of treatment benefits for individuals.
TL;DR: This work harnessed bioinformatics tools and a novel analytical framework to estimate mutation parameters for each STR in the human genome by correlating STR genotypes with local sequence heterozygosity and used these estimates to create a framework for measuring constraint at STRs by comparing observed versus expected mutation rates.
Abstract: Identifying regions of the genome that are depleted of mutations can distinguish potentially deleterious variants. Short tandem repeats (STRs), also known as microsatellites, are among the largest contributors of de novo mutations in humans. However, per-locus studies of STR mutations have been limited to highly ascertained panels of several dozen loci. Here we harnessed bioinformatics tools and a novel analytical framework to estimate mutation parameters for each STR in the human genome by correlating STR genotypes with local sequence heterozygosity. We applied our method to obtain robust estimates of the impact of local sequence features on mutation parameters and used these estimates to create a framework for measuring constraint at STRs by comparing observed versus expected mutation rates. Constraint scores identified known pathogenic variants with early-onset effects. Our metric will provide a valuable tool for prioritizing pathogenic STRs in medical genetics studies.
TL;DR: It is suggested that patients with ppFEV1<40 may benefit from treatment initiation at a lower dose with augmented monitoring before increasing to the full dose, as compared with patients with higher lung function.
TL;DR: It is shown here that adult T cells and hepatocytes can survive conditional inactivation of the Mad2l1 SAC gene and resulting CIN, suggesting differential selective pressures on the two tumor cell types.
Abstract: Chromosome instability (CIN) is deleterious to normal cells because of the burden of aneuploidy. However, most human solid tumors have an abnormal karyotype implying that gain and loss of chromosomes by cancer cells confers a selective advantage. CIN can be induced in the mouse by inactivating the spindle assembly checkpoint. This is lethal in the germline but we show here that adult T cells and hepatocytes can survive conditional inactivation of the Mad2l1 SAC gene and resulting CIN. This causes rapid onset of acute lymphoblastic leukemia (T-ALL) and progressive development of hepatocellular carcinoma (HCC), both lethal diseases. The resulting DNA copy number variation and patterns of chromosome loss and gain are tumor-type specific, suggesting differential selective pressures on the two tumor cell types.
TL;DR: It is shown that the long pharmacokinetic half-life of 15a combined with the high drug concentrations ensured prolonged CCR2 occupancy and rendered 15a a promising compound for drug development and confirms high receptor occupancy as a key parameter when targeting chemokine receptors.
Abstract: CC Chemokine Receptor 2 (CCR2) and its endogenous ligand CCL2 are involved in a number of diseases, including atherosclerosis. Several CCR2 antagonists have been developed as potential therapeutic agents, however their in vivo clinical efficacy was limited. In this report, we aimed to determine whether 15a, an antagonist with a long residence time on the human CCR2, is effective in inhibiting the development of atherosclerosis in a mouse disease model. First, radioligand binding assays were performed to determine affinity and binding kinetics of 15a on murine CCR2. To assess the in vivo efficacy, western-type diet fed apoE−/− mice were treated daily with 15a or vehicle as control. Treatment with 15a reduced the amount of circulating CCR2+ monocytes and the size of the atherosclerotic plaques in both the carotid artery and the aortic root. We then showed that the long pharmacokinetic half-life of 15a combined with the high drug concentrations ensured prolonged CCR2 occupancy. These data render 15a a promising compound for drug development and confirms high receptor occupancy as a key parameter when targeting chemokine receptors.
14 Jul 2017
TL;DR: In this article, the authors assess the current regulatory environment, relevant regulations and guidelines, and their impact on continuous manufacturing and identify regulatory gaps and challenges and propose a way forward to facilitate implementation.
Abstract: This paper assesses the current regulatory environment, relevant regulations and guidelines, and their impact on continuous manufacturing. It summarizes current regulatory experience and learnings from both review and inspection perspectives. It outlines key regulatory aspects, including continuous manufacturing process description and control strategy in regulatory files, process validation, and other key GMP requirements. In addition, the paper identifies regulatory gaps and challenges and proposes a way forward to facilitate implementation.
Amgen1, Princeton University2, Bristol-Myers Squibb3, Biogen Idec4, Genentech5, Regeneron6, Hoffmann-La Roche7, Merck & Co.8, Pfizer9, Silver Spring Networks10, Daiichi Sankyo11, National Institute for Biological Standards and Control12, Health Canada13, GlaxoSmithKline14, Merck Serono15, MedImmune16, Vertex Pharmaceuticals17, Durham University18, Novo Nordisk19, United States Military Academy20, Alnylam Pharmaceuticals21, Janssen Pharmaceutica22, Rafael Advanced Defense Systems23
TL;DR: This 2017 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance.
Abstract: The 2017 11th Workshop on Recent Issues in Bioanalysis took place in Los Angeles/Universal City, California, on 3-7 April 2017 with participation of close to 750 professionals from pharmaceutical/biopharmaceutical companies, biotechnology companies, contract research organizations and regulatory agencies worldwide. WRIB was once again a 5-day, week-long event - a full immersion week of bioanalysis, biomarkers and immunogenicity. As usual, it was specifically designed to facilitate sharing, reviewing, discussing and agreeing on approaches to address the most current issues of interest including both small- and large-molecule analysis involving LC-MS, hybrid ligand-binding assay (LBA)/LC-MS and LBA approaches. This 2017 White Paper encompasses recommendations emerging from the extensive discussions held during the workshop, and is aimed to provide the bioanalytical community with key information and practical solutions on topics and issues addressed, in an effort to enable advances in scientific excellence, improved quality and better regulatory compliance. Due to its length, the 2017 edition of this comprehensive White Paper has been divided into three parts for editorial reasons. This publication (Part 3) covers the recommendations for large-molecule bioanalysis, biomarkers and immunogenicity using LBA. Part 1 (LC-MS for small molecules, peptides and small molecule biomarkers) and Part 2 (hybrid LBA/LC-MS for biotherapeutics and regulatory agencies' inputs) are published in volume 9 of Bioanalysis, issues 22 and 23 (2017), respectively.
TL;DR: Pimodivir has potential to not only reduce viral load but to have a clinical impact on patients as a novel treatment for influenza A virus infection and further trials are therefore warranted to assess pimodivIR.
Abstract: BackgroundPimodivir (formerly JNJ-63623872) is a novel, non-nucleoside polymerase complex inhibitor with in vitro activity against influenza A virus, including pandemic 2009 H1N1, H7N9, H5N1 strain...
TL;DR: Ivacaftor treatment in prepubescent children may help to address short stature and altered GV in children with CF; results from these analyses support the existence of an intrinsic defect in the growth of children withCF that may be ameliorated by CFTR modulation.
Abstract: BACKGROUND AND OBJECTIVES: Cystic fibrosis (CF) is known for its impact on the lung and pancreas of individuals; however, impaired growth is also a common complication. We hypothesized that targeting the biological defect in the CF transmembrane conductance regulator (CFTR) protein may affect growth outcomes. METHODS: In this post hoc analysis, we assessed linear growth and weight in 83 children (aged 6–11 years) enrolled in 2 clinical trials, the longitudinal-observation GOAL study and the placebo-controlled ENVISION study, to evaluate the effects of ivacaftor, a CFTR potentiator. We calculated height and weight z scores and height and weight growth velocities (GVs). RESULTS: In ivacaftor-treated children in GOAL, height and weight z scores increased significantly from baseline to 6 months (increases of 0.1 [P CONCLUSIONS: Ivacaftor treatment in prepubescent children may help to address short stature and altered GV in children with CF; results from these analyses support the existence of an intrinsic defect in the growth of children with CF that may be ameliorated by CFTR modulation.
TL;DR: An organic solvent sample preparation approach was developed to optimize extraction recovery and minimize the HCT effect on the analysis of VAMS dried blood samples.
Abstract: Aim: Volumetric absorptive microsampler (VAMS) was designed to sample a fixed volume of blood regardless of the hematocrit (HCT) levels. Model compounds with a wide range of hydrophobicity were evaluated for their extraction recoveries from VAMS dried blood samples. Results: For the highly hydrophobic compounds, recoveries with methanol or methanol/acetonitrile extraction were higher compared with using the aqueous mixture of methanol or acetonitrile. Extraction with methanol/acetonitrile (1:1) yielded more consistent recovery across the HCT range of 20–70% than using methanol alone, with good linearity, accuracy and precision achieved from 1 to 2000 ng/ml. Conclusion: An organic solvent sample preparation approach was developed to optimize extraction recovery and minimize the HCT effect on the analysis of VAMS dried blood samples.
TL;DR: Reducing lipophilicity improved antimycobacterial activity with the most potent compounds achieving minimum inhibitory concentrations ranging from 3 to 5 μM (1-2 μg/mL) against the H37Ra isolate of M. tuberculosis.
Abstract: Drug resistant tuberculosis (TB) infections are on the rise and antibiotics that inhibit Mycobacterium tuberculosis through a novel mechanism could be an important component of evolving TB therapy. Protein kinase A (PknA) and protein kinase B (PknB) are both essential serine-threonine kinases in M. tuberculosis. Given the extensive knowledge base in kinase inhibition, these enzymes present an interesting opportunity for antimycobacterial drug discovery. This study focused on targeting both PknA and PknB while improving the selectivity window over related mammalian kinases. Compounds achieved potent inhibition (Ki ≈ 5 nM) of both PknA and PknB. A binding pocket unique to mycobacterial kinases was identified. Substitutions that filled this pocket resulted in a 100-fold differential against a broad selection of mammalian kinases. Reducing lipophilicity improved antimycobacterial activity with the most potent compounds achieving minimum inhibitory concentrations ranging from 3 to 5 μM (1–2 μg/mL) against the ...
TL;DR: A new and favorable nature of solubility-permeability interplay was revealed in this work: delivering high supersaturation level of the BCS class IV drug rifaximin via ASD, thereby saturating the drugs’ P-gp-mediated efflux transport, led to the favorable unique win-win situation, where both thesolubility and the permeability increased simultaneously.
Abstract: Rifaximin is a BCS class IV (low-solubility, low-permeability) drug and also a P-gp substrate. The aims of this work were to assess the efficiency of different rifaximin amorphous solid dispersion (ASDs) formulations in achieving and maintaining supersaturation and to investigate the consequent solubility-permeability interplay. Spray-dried rifaximin ASDs were prepared with different hydrophilic polymers and their ability to achieve and maintain supersaturation was assessed. Then, rifaximin’s apparent intestinal permeability was investigated as a function of increasing supersaturation both in vitro using the parallel artificial membrane permeability assay (PAMPA) and in vivo using the single-pass rat intestinal perfusion (SPIP) model. The efficiency of the different ASDs to achieve and maintain supersaturation of rifaximin was found to be highly polymer dependent, and the copovidone/HPC-SL formulation was found to be superior to the other two, allowing supersaturation of 200× that of the crystalline solubility for 20 h. In vitro, rifaximin flux was increased and the apparent permeability was constant as a function of increasing supersaturation level. In vivo, on the other hand, absorption rate coefficient (k
a) was first constant as a function of increasing supersaturation, but at 250×, the crystalline solubility k
a was doubled, similar to the k
a in the presence of the strong P-gp inhibitor GF120918. In conclusion, a new and favorable nature of solubility-permeability interplay was revealed in this work: delivering high supersaturation level of the BCS class IV drug rifaximin via ASD, thereby saturating the drugs’ P-gp-mediated efflux transport, led to the favorable unique win-win situation, where both the solubility and the permeability increased simultaneously.
TL;DR: This work explored two strategies to eliminate observed aldehyde oxidase (AO)-mediated metabolism at the 2-position of these 7-azaindole analogues and identified multiple 2-substituted 7-azerous analogues with enhanced AO stability and one such compound is presented that demonstrates a favorable oral pharmacokinetic profile in rodents.
Abstract: JNJ-63623872 (2) is a first-in-class, orally bioavailable compound that offers significant potential for the treatment of pandemic and seasonal influenza. Early lead optimization efforts in our 7-azaindole series focused on 1,3-diaminocyclohexyl amide and urea substitutions on the pyrimidine-7-azaindole motif. In this work, we explored two strategies to eliminate observed aldehyde oxidase (AO)-mediated metabolism at the 2-position of these 7-azaindole analogues. Substitution at the 2-position of the azaindole ring generated somewhat less potent analogues, but reduced AO-mediated metabolism. Incorporation of a ring nitrogen generated 7-azaindazole analogues that were equipotent to the parent 2-H-7-azaindole, but surprisingly, did not appear to improve AO-mediated metabolism. Overall, we identified multiple 2-substituted 7-azaindole analogues with enhanced AO stability and we present data for one such compound (12) that demonstrate a favorable oral pharmacokinetic profile in rodents. These analogues have th...
TL;DR: Most patients experience ≥1 PEx annually, and nearly half require IV antibiotics and/or inpatient stay at considerable cost, which is similar to the cost of pulmonary exacerbations among patients with cystic fibrosis in the United States.
Abstract: Background: Information is limited regarding the cost of pulmonary exacerbations (PEx) among patients with cystic fibrosis in the United States.Methods: To examine PEx costs, medical chart data wer...
TL;DR: Motion-artifact-free, high signal-to-noise ratio (SNR) images of lung ventilation were obtained; focal ventilation defects were found in patients with respiratory diseases.
TL;DR: The PBPK results suggest there is a potential for DDI between dasabuvir and clopidogrel, but the magnitude is not expected to be clinically relevant.
Abstract: Dasabuvir, a nonnucleoside NS5B polymerase inhibitor, is a sensitive substrate of cytochrome P450 (CYP) 2C8 with a potential for drug-drug interaction (DDI) with clopidogrel. A physiologically based pharmacokinetic (PBPK) model was developed for dasabuvir to evaluate the DDI potential with clopidogrel, the acyl-β-D glucuronide metabolite of which has been reported as a strong mechanism-based inhibitor of CYP2C8 based on an interaction with repaglinide. In addition, the PBPK model for clopidogrel and its metabolite were updated with additional in vitro data. Sensitivity analyses using these PBPK models suggested that CYP2C8 inhibition by clopidogrel acyl-β-D glucuronide may not be as potent as previously suggested. The dasabuvir and updated clopidogrel PBPK models predict a moderate increase of 1.5-1.9-fold for Cmax and 1.9-2.8-fold for AUC of dasabuvir when coadministered with clopidogrel. While the PBPK results suggest there is a potential for DDI between dasabuvir and clopidogrel, the magnitude is not expected to be clinically relevant.
TL;DR: The IWG conducted an anonymous survey among IQ member companies to query current practices, focusing specifically on the aforementioned key points, and presented consensus recommendations on downregulation, CYP2C induction, and CyP2B6 positive control.
Abstract: The European Medicines Agency (EMA), the Pharmaceutical and Medical Devices Agency (PMDA), and the Food and Drug Administration (FDA) have issued guidelines for the conduct of drug-drug interaction studies. To examine the applicability of these regulatory recommendations specifically for induction, a group of scientists, under the auspices of the Drug Metabolism Leadership Group of the Innovation and Quality (IQ) Consortium, formed the Induction Working Group (IWG). A team of 19 scientists, from 16 of the 39 pharmaceutical companies that are members of the IQ Consortium and two Contract Research Organizations reviewed the recommendations, focusing initially on the current EMA guidelines. Questions were collated from IQ member companies as to which aspects of the guidelines require further evaluation. The EMA was then approached to provide insights into their recommendations on the following: 1) evaluation of downregulation, 2) in vitro assessment of CYP2C induction, 3) the use of CITCO as the positive control for CYP2B6 induction by CAR, 4) data interpretation (a 2-fold increase in mRNA as evidence of induction), and 5) the duration of incubation of hepatocytes with test article. The IWG conducted an anonymous survey among IQ member companies to query current practices, focusing specifically on the aforementioned key points. Responses were received from 19 companies. All data and information were blinded before being shared with the IWG. The results of the survey are presented, together with consensus recommendations on downregulation, CYP2C induction, and CYP2B6 positive control. Results and recommendations related to data interpretation and induction time course will be reported in subsequent articles.
TL;DR: A sustained and significant role is confirmed for ZFHX3 in maintaining rhythmicity in the adult mammalian circadian system using tamoxifen treatment.
Abstract: The transcription factor zinc finger homeobox 3 (ZFHX3) plays a key role in coupling intracellular transcriptional-translational oscillations with intercellular synchrony in mouse suprachiasmatic nucleus (SCN). However, like many key players in central nervous system function, ZFHX3 serves an important role in neurulation and neuronal terminal differentiation while retaining discrete additional functions in the adult SCN. Recently, using a dominant missense mutation in mouse Zfhx3, we established that this gene can modify circadian period and sleep in adult animals. Nevertheless, we were still concerned that the neurodevelopmental consequences of ZFHX3 dysfunction in this mutant may interfere with, or confound, its critical adult-specific roles in SCN circadian function. To circumvent the developmental consequences of Zfhx3 deletion, we crossed a conditional null Zfhx3 mutant to an inducible, ubiquitously expressed Cre line (B6.Cg-Tg(UBC-cre/ERT2)1Ejb/J). This enabled us to assess circadian behavior in the same adult animals both before and after Cre-mediated excision of the critical Zfhx3 exons using tamoxifen treatment. Remarkably, we found a strong and significant alteration in circadian behavior in tamoxifen-treated homozygous animals with no phenotypic changes in heterozygous or control animals. Cre-mediated excision of Zfhx3 critical exons in adult animals resulted in shortening of the period of wheel-running in constant darkness by more than 1 h in the majority of homozygotes while, in 30% of animals, excision resulted in complete behavioral arrhythmicity. In addition, we found that homozygous animals reentrain almost immediately to 6-h phase advances in the light-dark cycle. No additional overt phenotypic changes were evident in treated homozygous animals. These findings confirm a sustained and significant role for ZFHX3 in maintaining rhythmicity in the adult mammalian circadian system.
TL;DR: Although the sweat test is considered a robust measure, sweat chloride measurements in patients with CF and a G551D mutation had an inherent biological variability that is higher than commonly considered.