Challenge #6

Hit Identification
Method type (check all that applies)
De novo design
High-throughput docking
Machine learning
Physics-based
Other (specify)
Scaffold Hopping, Bioisostere replacement, Pharmacophore Modeling, Molecular Fingerprints and Similarity/Analogs searching, Strain Fingerprints, Interaction Fingerprints, REOS, Lilly and other MedChem Filters
Description of your approach (min 200 and max 800 words)

Tailored Approach for CACHE Challenge Campaign 

Our CACHE challenge campaign integrates several advanced methodologies to create a comprehensive and dynamic drug discovery process. Here’s how we plan to execute this: 

  Molecular Dynamics (MD) Simulation 

We start with MD simulations to provide a detailed, atomic-level analysis of the target protein's behavior. By simulating the movements of atoms and molecules over time, MD reveals dynamic processes and conformational changes in different sites and sub-pockets of the protein structure. Unlike static methods such as X-ray crystallography, MD simulations illustrate how the protein evolves, interacts, and adapts, offering profound insights into stability, flexibility, and interaction patterns with candidate binders under physiological conditions. 

  Investigation of Critical Interactions 

Next, we focus on identifying crucial binding sites and interaction networks within the biological system. This step involves an in-depth analysis of pivotal interactions, essential for understanding the system's biological function. By mapping these interactions, we can pinpoint strategic sites for ligand binding and potential disruption, guiding the rational design of targeted therapies. 

  Machine Learning (ML) 

Leveraging ML techniques, we predict properties and activities of compounds using various molecular descriptors. We train ML models on extensive datasets to discern complex patterns and correlations, enhancing the efficiency and accuracy of the compound screening process. The ability of ML models to continuously learn and improve from new data provides a dynamic and robust tool for accelerating drug discovery and optimizing lead compounds. 

  Filtering with Selected Cutoffs 

We streamline the selection process by applying carefully chosen cutoffs for key parameters. This strategic filtering narrows down the pool of potential compounds, ensuring that only the most promising candidates progress. Setting precise thresholds for critical criteria prioritizes compounds with the highest likelihood of success while removing compounds with unwanted properties (i.e., PAINS, Lilly, BRENK, etc.)  

  High-Throughput Screening (Molecular Docking) 

We utilize high-throughput molecular docking to rapidly screen extensive libraries of compounds, predicting binding affinities and orientations within the target binding site. This approach allows for the efficient evaluation of large numbers of compounds, accelerating the discovery of promising candidates for further development. High-throughput screening quickly generates detailed insights into the interactions between potential drugs and their targets. Using docking scores and a set of other criteria, we select most promising candidate compounds for further forensic manual inspection (so called “cherry-picking party”)

  Scaffold Hopping and Bioisosteric Replacement 

To explore a broad spectrum of chemical scaffolds capable of binding to the target site, we employ scaffold hopping and bioisosteric replacement. Scaffold hopping explores alternative core structures, while bioisosteric replacement substitutes atoms or functional groups to maintain or enhance biological activity. These techniques enable the discovery of new leads with similar pharmacological profiles but distinct molecular architectures, fostering innovation and efficacy in drug discovery. 

  Hit-to-Lead Optimization 

Upon identifying initial hits, we refine compound properties such as potency, selectivity, and pharmacokinetic profiles through hit-to-lead optimization. This process involves iterative cycles of synthesis and testing, designed to enhance desired characteristics. By systematically modifying the molecular architecture and conducting structure-activity relationship studies, we aim to achieve optimal therapeutic efficacy and safety, transforming promising hits into lead compounds worth of subjecting to preclinical and clinical evaluation. 

  Next Stage of Molecular Docking in Conjunction and MD Simulation 

Our optimized leads would undergo rigorous validation through advanced molecular docking followed by MD simulations. This stage corroborates the binding interactions and structural stability of the leads, ensuring their robustness and desired biological activity. Computational scrutiny provides insights into binding affinities, conformational dynamics, and behavior within the biological milieu, validating the leads' potential and informing further optimization strategies. 

  Handling Massive Chemical Spaces 

Our expertise in handling large chemical spaces, including the REAL Database and REAL Space with over 39 billion molecules, positions us at the forefront of molecular exploration. Using cutting-edge computational methodologies and scalable infrastructure, we efficiently screen and analyze ultra-large compound libraries, accelerating drug discovery and innovation. 

  Rigorous Parameter Selection and Validation 

We meticulously evaluate and validate every parameter at each stage of our workflow against pertinent data. Our approach prioritizes robustness and reliability, ensuring each step is optimized for accurate and meaningful results. While adhering to established virtual screening protocols, we remain flexible and innovative, exploring novel strategies to push the boundaries of drug discovery.

What makes your approach stand out from the community? (<100 words)

Our approach offers individually tailored solutions with advanced techniques like MD simulations, machine learning, and molecular docking. We emphasize data-driven decision-making, validation, and iterative optimization for reliable results. Our expertise spans cheminformatics, combinatorial chemistry, and ultra-large datasets, exemplified by managing billions of molecules in our Enamine REAL Database and REAL Space collections. Our innovative, flexible workflow aligns precisely with contemporary CADD needs and challenges.

Method Name
EntelliMix (Enamine Intelligent Mix of CADD tools)
Commercial software packages used

Schrodinger Suite 2024-1 (Prime, Glide, Induced Fit Docking, Desmond, Phase, Canvas, QSAR, LigPrep, etc.)  

PyMOL

Chemaxon (JChem Engines) 

Free software packages used

RDKit Library

AutoDock

R

Python

Bash (shell)

Enamine in-house scripts

Relevant publications of previous uses by your group of this software/method

1. When yield prediction does not yield prediction: an overview of the current challenges. J. Chem. Inf. Model. 2024, 64, 1, 42–56 Publication Date:December 20, 2023. https://doi.org/10.1021/acs.jcim.3c01524&nbsp;

2. 2-Oxabicyclo[2.2.2]octane as a new bioisostere of the phenyl ring. Nat Commun 14, 5608 (2023). https://doi.org/10.1038/s41467-023-41298-3.

3. Creation of targeted compound libraries based on 3D shape recognition. Mol Divers 2022, 27, 939–949. DOI: 10.1007/s11030-022-10447-z 

4.Virtual Screening in Search for a Chemical Probe for Angiotensin-Converting Enzyme 2 (ACE2). Molecules. 2021 Dec 14;26(24):7584. doi: 10.3390/molecules26247584. PMID: 34946667; PMCID: PMC8707431. 

5. Pharmacological inhibition of syntenin PDZ2 domain impairs breast cancer cell activities and exosome loading with syndecan and EpCAM cargo. J of Extracellular Vesicle 2020, 10. DOI: 10.1002/jev2.12039 

6. Modelling of an autonomous Nav1.5 channel system as a part of in silico pharmacology study. J Mol Model 2021, 27. DOI: 10.1007/s00894-021-04799-w 

7. Integrated workflow for the identification of new GABA positive allosteric modulators based on the in silico screening with further in vitro validation. Molecular Informatics 2023. DOI: 10.1002/minf.202300156