Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) ion channel are established as the primary causative factor in the devastating lung disease cystic fibrosis (CF). More recently, cigarette smoke exposure has been shown to be associated with dysfunctional airway epithelial ion transport, suggesting a role for CFTR in the pathogenesis of chronic obstructive pulmonary disease (COPD). Here, the identification and characterization of a high throughput screening hit 6 as a potentiator of mutant human F508del and wild-type CFTR channels is reported. The design, synthesis, and biological evaluation of compounds 7-33 to establish structure-activity relationships of the scaffold are described, leading to the identification of clinical development compound icenticaftor (QBW251) 33, which has subsequently progressed to deliver two positive clinical proofs of concept in patients with CF and COPD and is now being further developed as a novel therapeutic approach for COPD patients.
Optimization of a 7-azaindole-3-acetic acid CRTh2 receptor antagonist chemotype derived from high throughput screening furnished a highly selective compound NVP-QAV680 with low nM functional potency for inhibition of CRTh2 driven human eosinophil and Th2 lymphocyte activation in vitro. The molecule exhibited good oral bioavailability in the rat, combined with efficacy in rodent CRTh2-dependent mechanistic and allergic disease models and was suitable for clinical development.
A HPLC gradient methodology using immobilized human serum albumin (HSA) and rat serum albumin (RSA) has been used as a tool to investigate the protein binding trends of novel discovery compounds. These methods have been set up to support a high throughput approach and have been shown to be complementary to one another. Significant binding differences have been observed with some compounds when both methods have been employed. Discovery chemists are now also able to rank order molecules using these quick otrend analysiso albumin binding screens by submitting a 20l sample from the 10mM stock solution from the inhouse compound archive. Additionally, chemists have the opportunity to predict trends in albumin binding by use of an internal QSAR model based upon a diverse 1200 compound result set, which had been previously analyzed with the HSA methodology.
Genetic Engineering & Biotechnology NewsVol. 31, No. 12 TutorialLab Transport and Management SystemLAB2LAB Designed to Connect Remote Labs to a Central Instrument FacilityPublished Online:1 Sep 2011https://doi.org/10.1089/gen.31.12.10AboutSectionsView articleView Full TextPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View articleFiguresReferencesRelatedDetails Volume 31Issue 12Jun 2011 Information© 2011 by GEN PublishingTo cite this article:Wendy Gaisford, Brian Everatt.Lab Transport and Management System.Genetic Engineering & Biotechnology News.Jun 2011.28-29.http://doi.org/10.1089/gen.31.12.10Published in Volume: 31 Issue 12: September 1, 2011PDF download
High non-specific binding (NSB) is one of the most common reasons for candidate failure in potential positron emission tomography (PET) radiotracer development. It is of interest to develop high throughput in vitro methods for predicting non-specific binding prior to radiolabeling, which would help guide radiotracer candidate selection and assist decision making in new radiotracer discovery. We evaluated several electrokinetic chromatographic (EKC) systems to help identify PET ligands with low non-specific binding characteristics by mimicking the ligand–brain tissue interaction. The measured retention factors of tracers in clinical use or terminated candidates within AOT vesicle EKC systems were compared with literature in vitro or in vivo NSB data. We conclude that there is a statistical correlation between the chromatographic retention parameters of tested drugs and their NSB. The AOT vesicle EKC method can provide NSB in vitro trend analysis for a large number of drug candidates early in the novel radiotracer discovery process with minimal resources.
A novel porous zwitterionic monolith was prepared by thermal co-polymerisation of 2-methacryloyloxyethyl phosphorylcholine (MPC) and ethylene glycol dimethacrylate (EDMA) within 100 μm I.D. capillaries. Mercury intrusion porosimetry, scanning electron microscopy (SEM), micro-HPLC (μ-HPLC), elemental analysis and ζ-potential analysis were used to evaluate the monolithic structure. No evidence of swelling or shrinking of the monolith in different polarity solvents was observed. A typical hydrophilic liquid chromatography (HILIC) mechanism was observed at high organic solvent content (acetonitrile >60%). The phosphorylcholine (PC) functionality has both a positively charged quaternary ammonium and a negatively charged phosphate group. For charged analytes, a weak electrostatic interaction was also observed by studying the influence of mobile phase pH and salt concentration on their retentions on the poly(MPC-co-EDMA) monolithic column. The optimised poly(MPC-co-EDMA) monolith showed very good selectivities for a range of polar test analytes, especially small peptides. This might be ascribed to the good biocompatibility of PC functionality. At low organic solvent content, baseline separation was also observed for a test mixture of seven alkylphenones by a reversed-phase separation mechanism.
Lung tissue distribution of an inhaled drug is important for its potency in the airways and with minimum systemic effects within its dose range. As the lung has the smallest diffusion distance of all the organs in the body and negligible diffusion delays, the characteristics of drug distribution in the lung will mainly depend on drug binding to both tissue and plasma protein. This research aims to develop and evaluate surfactant vesicle electrokinetic chromatography (SEKC) methods for high throughput profile prediction of tissue distribution for inhaled drugs. Several electrokinetic chromatography methods reported in the literature, as well as immobilised artificial membrane chromatography, were compared and evaluated in respect to chromatographic characteristics and statistical correlations. Among these methods, the docusate sodium salt (AOT) SEKC system showed good reproducibility, short run time, and the highest selectivity for alkylphenone test compounds. It also showed a significant statistical correlation between the retention of inhaled drugs and their in vivo volume of distribution at steady-state (V(ss)) in whole human body neglecting the plasma protein-binding differences. Stronger correlations were observed between the AOT SEKC retention of a series of basic drugs and their rat lung tissue-to-plasma water partitioning coefficient (K(pu)), which is affected only by drug binding to the tissue constituent. Further, on comparing correlations between AOT SEKC retention and K(pu) at various rat tissues, it was observed that the strongest correlation was with lung tissue distribution, while the weakest was with brain tissue distribution.
A new procedure for the determination of novel discovery drug substance purity was developed using LC-MS coupled with charged aerosol detection (CAD) in a walk up open access system and chromatographic purity service. Chemists require an accurate high throughput methodology to monitor reactions and to provide good assurance of final compound quality. There is a need for detection methodologies, which are accurate and precise and offer rapid, inexpensive evaluation of research compound purity without the need for specific validated drug reference standards. This new approach resulted in a more accurate assessment of purity in comparison to the standard UV approach. This technique has been successful as an approach for a walk up service for chemists and also as a chromatographic purity service at low pH.
High throughput screening identified a phenoxyacetic acid scaffold as a novel CRTh2 receptor antagonist chemotype, which could be optimised to furnish a compound with functional potency for inhibition of human eosinophil shape change and oral bioavailability in the rat.
AbstractReaction of the macrocyclic polyamine (I) with formaldehyde (II) yields the N‐formyl‐N'‐methylhexahydropyrimidine (III) which is also obtained from 1,3‐diaminopropane (IV) and (II).