Post on 14-Jul-2015
The Shape of Cures to Come™
Cubist Pharmaceuticals
A chemistry friendly system integrating drug design tools and a consistent visual interface
Xin Zhang, Christian Baber
Outline
Introduction to drug metabolism
Introduction to Cubist Discovery Informatics group
The DT workbench
Case study
Outline
Introduction to drug metabolism
Introduction to Cubist Discovery Informatics group
The DT workbench
Case study
Drug metabolism
Convert drugs into other products (metabolites) within the body
Controls the duration and intensity of the action of many drugs
Over 50% of drug development failures can be associated with metabolic effects
In general metabolites are more easily excreted than the original drug
Secondary pharmacological implications
– Normally pharmacologically inert
– Sometime they are pharmacologically active.
• similar activity to the drug
• or a different activity
• or be toxic
Ticrynafen
A diuretic drug to treat hypertension
Withdrawn in 1980 only a few months after launched
Several hundred cases of liver injury reported, 25 deaths
Covalent binding of metabolites to human liver microsomes reported
Cytochrome P450 isozyme 2C9(CYP2C9)
Thiophene epoxide Thiophene sulfoxide
Reactive
Reactive
RS Predictor – A SOM Prediction Model
Models predict site of metabolism (SOM) for given structures
A QSAR model developed by Prof. Breneman’s group in Rensselaer Polytechnic Institute *
Isozyme specific, 9 available
– Cytochrome P450 isozymes 1A2, 2A6, 2B6, 2C19, 2C8, 2C9, 2D6, 2E1, and 3A4
Academic scientific project with technical limitations
– Command line only, no graphic interface
– Structure files input/output – bad for chemists
– Single user only, not capable of running predictions simultaneously
– Dependencies on MOE and MatLab
* Jed Zaretzki, Patrik Rydberg, Charles Bergeron, Kristin P. Bennett, Lars Olsen, and Curt M. Breneman, J. Chem. Inf. Model. 2012, 52, 1637−1659
RS Predictor at Cubist
Modify the run scripts to manage
– MOE floating licenses
– Matlab license
– Multiple users, not overwrite results
– Simultaneous runs
– Output result folders
Allow input structure from a drawing package
– MarvinSketch
Visualize the prediction results
– MarvinView (customized to display atom label and highlight)
More details on integration later
Outline
Introduction to drug metabolism
Introduction to Cubist Discovery Informatics group
The DT workbench
Case study
Discovery Informatics
Not a software development team– involved in bringing in new technologies
Part of Discovery Technologies (DT) - a hybrid group consisting of– chemo- and bio- informatics– molecular modeling– compound management– High Throughput Screening – NMR / Biophysics
Every cheminformatician supports at least one research project– Driving project SAR– Generating ideas using computational technologies– Ensuring the availability & integration of data– Chemical and biological data management
Outline
Introduction to drug metabolism
Introduction to Cubist Discovery Informatics group
The DT workbench
Case study
DT Workbench - background
Used to publish models for access by chemists
– User friendly, web based instead of script based
– Many expert tools are command line only
– Created, maintained, and expanded by DT scientists, not IT
Feedback has been very positive
– Started as a prototype in 2008
– Lead to substantial update in 2012
• ChemOffice replaced by ChemAxon Marvin
• Increased usage since updates
Low maintainence: 3tier web-based system
– Thin client that utilize existing servers and storage disks
– No installation at the user end
Templates: Consistent but customizable front end
– Apps have different fields depends on inputs parameters
– Templates allow reuse of existing forms
– Common components reduces training requirement
Scalability: Re-designed system architecture to incorporate new technologies, such as Marvin suite for both input and visualization
DT workbench – main user interface
Tree menu organizes tools/models
Consistent layout
Option to retrieve result by email – for big jobs
• Customizable input form depends on run parameters
• Templates based system allow reuse of existing forms
Integrated Marvin Sketch Applet, no end user software installation- especially important for end users without admin privileges
ChemAxon components in Pipeline Pilot used to calculate some properties
System Architecture- the design for DT workbench
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DT Workbench
MarvinSketch AppletMarvinView Applet
System Architecture- the design for DT workbench
MarvinSketch AppletMarvinView Applet
• Communicate back to Tomcat server to send the structure data• Compatible with Cubist supported browser and platform• Better fit within W3C standard HTML than ActiveX (ChemDraw)• Communication between Javascript and Java - enable interactive view
Outline
Introduction to drug metabolism
Introduction to Cubist Discovery Informatics group
The DT workbench
Case study
Case study
Identify potential liability of Ticrynafen by predicting its SOM
Lead hopping – searching new ideas
Evaluating the new structure – overlay with Ticrynafen
Start with Ticrynafen’s structure
Integrated with Marvin Sketch for structure drawing
Cytochrome P450 isozymemodel to use
Running prediction on the server
Change your mind after job submitted? You can still get the results by email
Information about the Job: task name, and status
Predicted results – identified site of metabolism
Customized MarvinView to visualize predicted results- Critical information is directly displayed on
the structure- Thanks to Marvin API, difficult to do this
with ChemDraw
Predicted result is from scripts in sdf file format – no interface
Thiophene is the main site of
metabolism
Part of MarvinView, automatically display relevant properties based on model run
Highlight the primary SOM
Label the SOM atoms
Predicted results – identified site of metabolism
SOM_viewer.jsp
• Simple coding with Marvin API• Self-taught by reading ChemAxon Documents
Case studies
Identify potential liability of Ticrynafen by predicting its SOM
Lead hopping – searching new ideas
Evaluating the new structure – overlay with Ticrynafen
Thiophene replacement – Lead hopping
Take the output of current run into the next job
Thiophene was identified as primary site
of metabolism so we want to replace it
Thiophene replacement – Lead hopping
Find replacement with similar biological activity
Similar Template
2D Structure View – Multiple compounds
Customized interface
Integrated with Knime– Knime pre-processes the SDF file
• Standardize structures / tidy file
• Chunk file for multiple page display
MarvinView API used
– Table layout
– Structure display parameters
– Event listener, etc.
Switch view types Display by pages
Toggle to display/hide properties
Thiophenereplacements
Case studies - continue
Identify potential liability of Ticrynafen by predicting its SOM
Lead hopping – searching new ideas
Evaluating the new structure – overlay with Ticrynafen
3D structure overlay
3D structure viewer – jmolNeeds improvement
MarvinSpace evaluated, but not adopted due to slow loading of pdbfiles in our server environment
2D structure viewer – not relevant here
Drug metabolism prediction and drug design
Ticrynafen(withdrawn in 1980)
TertiaryCPrimary
O
O
OH
O
SSecondary
Cl
Cl
Predicted primary SOM
non-standard bioisostere
Edecrin by Merck(approved in 1999)
bioisostere
Summary
Metabolism Plays Central Role in Drug Discovery– Computational models can help
Integrated Web-based Applications Reduce Learning Curves– Standard components and templates
Technologies such as Marvin enable Quick, Inexpensive, Simple Solutions– 6 month develop by a co/op student from North Eastern university
– Low maintenance - requires no additional IT support
Marvin Sketch Applet is Consistent but Flexible– Easily implemented in web pages - no end user installation
– Wide range of file formats allows common interface for different Workbench models
Marvin View/Structure Renderer is Adaptable to Various Needs – Highlight specified atoms & bonds
– Add labeling and captioning text
– Interactive Spreadsheet and Grid formats available
Don’t be Limited by the Out of Box Interfaces– Marvin customization is easy