SpeedScreen: The “Missing Link” between Genomics and Lead Discovery

Abstract

SpeedScreen is a novel, label-free, in-solution, affinity-based selection methodology for high-throughput screening (HTS) developed at Novartis Pharma. The SpeedScreen protocol comprises in-solution affinity selection, followed by size exclusion chromatography in combination with microbore-liquid-chromatography/electrospray-ionization mass spectrometry (micro-LC/ESI-MS). The authors describe the basic concept behind assay development, HTS, and data analysis with the SpeedScreen technology. Advantages and limitations of SpeedScreen compared to alternative screening technologies are discussed, and an example is given from a SpeedScreen campaign applying this innovative affinity selection concept in HTS.

Multiple ligand detection and affinity measurement by ultrafiltration and mass spectrometry analysis applied to fragment mixture screening

“…Techniques that assess the binding of candidate molecules to immobilized or soluble targets (often proteins) are gaining wide acceptance in high-throughput screening (HTS) laboratories as valuable complements to traditional drug discovery technologies [1][2][3]. A variety of protein targets have been evaluated by affinity-based HTS campaign, including those receptor-type targets that are difficult to screen using traditional biochemical assays or lack functional assays [4][5][6][7]. Commonly used techniques for ligand binding measurement in the drug discovery and development program include nuclear magnetic resonance (NMR) [8], surface plasmon resonance (SPR) [9], fluorescence monitoring [10], isothermal titration calorimetry (ITC) [11] and differential scanning calorimetry (DSC) [12].…”

A Chemoinformatics Analysis of Hit Lists Obtained from High-Throughput Affinity-Selection Screening

“…1,2 SpeedScreen has become one of the most frequently used HTS platforms at Novartis, especially when genomic targets with an unknown function (orphan targets) or targets with a known function but nontractable to a functional HTS have to be addressed. To achieve HTS performance despite the sequential MS readout, a primary SpeedScreen campaign is performed with pools of 400 compounds per well of the 96-well microplates.…”

“…Finally, the protein-ligand complex is disintegrated under the conditions used during a reversed-phase chromatography step, and the column effluent is directed to the ion trap MS detector with electrospray ionization. 2 A software program enables fully automated comparison of the observed m/z values with the known molecular masses of the pooled compounds to identify binder molecules.…”

High-Throughput Affinity-Based Technologies for Small-Molecule Drug Discovery

“…39 In size exclusion separation, a size exclusion chromatography (SEC) column is used to separate bound from unbound compounds. Two technologies are well established for high-throughput SEC-MS: SpeedScreen (Novartis, Basel, Switzerland), which can handle 400 compounds per mixture, 36 and ALIS (Automated Ligand Identification System; Schering-Plough, Kenilworth, NJ), which can handle 2500 per mixture. 37 There are slight differences between the two technologies: spin columns in plate format are used in SpeedScreen versus an array of continuous-flow SEC columns used in ALIS; in addition, ion trap MS is used in SpeedScreen versus time-of-flight MS used in ALIS.…”

“…[36][37][38] Generally, a separation step before MS detection is used to remove unbound compounds. The separation can be achieved by several means: affinity based, size exclusion, or ultrafiltration.…”