the trend to outsource computational chemistry€¦ · > cresset has been offering computational...
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The trend to outsource computational chemistry Dr Martin Slater Director of Consulting
© 2013 Cresset Group Ltd.
> Unprecedented change over the last 5 years > Turbulent times for the pharma industry > Trend for outsourcing chemistry – 2007-2012
A historical perspective on drug R&D
Areas / companies benefiting: Asia/US AMRI WuXi EU Evotec BioFocus/Argenta
© 2013 Cresset Group Ltd.
R&D budgets in decline
> R&D spend for pharmaceutical companies historically a larger proportion of sales than any other industry – including high tec - software, Aerospace
> Limited protection for the ROI > Patent cliff for several high earning drugs > Revenue swallowed up by the generics market
> ROI, now low hanging fruit gone, poor prospect for investors – perceived innovation deficit
> …….something had to give…………
© 2013 Cresset Group Ltd.
Drug discovery must continue…but…...how? > Further fragmentation of the drug the discovery process: > More focus given to collaborative working
> Open innovation - Eli Lilly > Virtual company models > Outsourcing / Offshoring – eg. ASIA
> Drug discovery elsewhere …..
> Not-for-profit organisations / Academia/ government sponsored ……..Quicker?……. Cheaper?..........Smarter!!
New opportunities - New models
© 2013 Cresset Group Ltd. 5
Where is comp. chem. useful in the DD process?
Drugability Lit.
precedence
Sequence analysis
chemogenomics
Protein modelling
3DQSAR target
3DQSAR off target Tox target
Optimisation selectivity properties
De-novo Ligand design
scaffold hopping
Bioisosteres Patent scope
Bioactive conformation Binding mode
Library design
Compound selection
Virtual screening
FBDD Fragment
joining
Peptide mimetic design
HTS rescue hit
expansion Thematic Analysis™: a chemogenomic approach to GPCR drug discovery. Crossley R , Macritchie JA , SlaterMJ . Current topics in medicinal chemistry 2011 ;11(15):1925-43
Sequence alignments
animal-human
De-novo Ligand design scaffold
hopping
Virtual screening
© 2013 Cresset Group Ltd. 6
Working with Cresset BMD
> Cresset has been offering computational chemistry as a service for a decade!
> Over a100 projects completed for customers.
> Enzymes, Channels, Receptors, Anti-infective
> We are now expanding this service and are offering an extremely flexible ‘Comp. Chem. On-Demand’ service
> Powerful combination > Unique software > Software infrastructure > Expertise
> scientists with frontline experience in drug discovery
© 2013 Cresset Group Ltd. 7
PDE5
11bHSD
CDK2
HIV NNRTI
CCK2
> Drug Discovery Projects • 100+ projects • 80%+ success rate • Wide range of targets
– GPCRs – Ion Channels – Kinases – Proteases – Protein-Protein Interactions – etc.
> Software Sales • Top 20 pharma comps • 20+ Biotechs • Top academics
Cresset’s Track Record
© 2013 Cresset Group Ltd. 9
Work in 2012
Completed 14 projects:
> Protease X2 Virtual screen /de-novo design > Nuclear hormone Patent protection Receptor > Antibacterial X3 3DQSAR/modelling Med.Chem.Support > Oncology target X2 Virtual screen/Med.Chem. Support > Antiviral Med. Chem Support > GPCR X3 Virtual screen / SAR field mapping > Antifungal 3D QSAR / prop. optimisation > Ion channel Virtual screen
© 2013 Cresset Group Ltd. 10
Typical tasks – 3D overlays of actives
© 2013 Cresset Group Ltd. 11
Typical tasks – de novo design / scaffold hop
© 2013 Cresset Group Ltd. 12
Typical tasks – de novo design / scaffold hop
© 2013 Cresset Group Ltd. 13
An Opportunity & a Challenge
> Provide a small diverse screening library 10K for a small biotech company > Diversity in potential biological targets to be hit
> Minimum redundancy in the set
> Maximum chance of success in finding a lead within
available budget and screening resources
© 2013 Cresset Group Ltd.
Initial thoughts
> Compare 3D and 2D similarities for compound collections - are we wasting our time?
> Take a small compound collection > Full NxN calculation > 3D method = Fields & Shape > 2D method = atom pairs
> Compare and Contrast
© 2013 Cresset Group Ltd.
Compound Collection
> BIONET 'Rule of Three' ('Ro3') Fragment Library: “7,907 'Ro3'-compliant fragments”
> Conformation hunt on every fragment Maximum of 5 conformations (!)
> Full N x N similarity matrix, 3D & 2D (60 Million data points)
> ~30 compounds failed conformation hunting
© 2013 Cresset Group Ltd.
Problems
> 400Mb of data > Tedious to use and examine Pilot study just using the first 500 compounds
> Some chemical families in this area
> Still a large dataset to deal with (250,000 data points)
> 2D similarities and fragments > Small changes cause disproportionately high changes
> Atom pairs particularly bad
> Switch to KNIME fingerprints
All 2D values lower than ‘normal’
© 2013 Cresset Group Ltd.
Comparing 2D and 3D metrics
Agreement
© 2013 Cresset Group Ltd.
N NHO
O
Cl
Example - Similar Scores
N NHO
O Cl
Cl
101 104 2D sim = 0.9
3D field sim = 0.87
© 2013 Cresset Group Ltd. 19
Example - Higher 3D Sim
2D sim = 0.1 (other methods=0.3)
3D field sim = 0.82
SO Br
N
HNO
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O
O
O
O
HN
Example - Higher 3D Sim
141
2D sim = 0.2
3D sim = 0.7
454
© 2013 Cresset Group Ltd.
So…
> Pilot study suggests some added value > Full matrix painful even if we could calculate it
> What about a reduced matrix?
> Use ‘Probe’ compounds to tease out molecules that are different in Field space
How many probes?
Across how many molecules
> We were running out of time…
© 2013 Cresset Group Ltd. 22
Compound selection by Field Diversity
> Proposed workflow for generation of a field diverse library:
9M
commercial compounds
Calc. 200 X 200 2D similarity
matrix
Pick 20K sub-set
Pick 100 Diverse
Field probes
Calc. Shape Diversity by
PMI
Pick 200 sub-set
Property Filters
Calc. 20K X 100
Field similarity matrix
Pick 12K Field
Diverse set
3D PCA on Field matrix
1.2M
© 2013 Cresset Group Ltd. 23
Field Diverse library: Outcome
12K ‘Field Diverse’ library mapped by 3D PCA on the 100 x 20,000 ‘Field Similarity Fingerprint’
Distinct separation of charged species within this space
Ammoniums Piperidines
….so what!!
Benzoic and aliphatic acids
© 2013 Cresset Group Ltd. 24
Field Diverse library: Outcome
12K ‘Field Diverse’ library mapped by 3D PCA
Distinct separation of by molecules by size within this space
….so what!!
Decreasing Size
© 2013 Cresset Group Ltd. 25
Deeper - Moderate ‘Field Similarity’
Alignment to ‘template1’
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Deeper - Moderate ‘Field Similarity’
Alignment to ‘template1’ Random selection of mols
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Deeper - Moderate ‘Field Similarity’
Alignment to ‘template’
© 2013 Cresset Group Ltd. 28
Is the chemical space sensible?
Small sulphonamides
Large esters
Two example clusters
© 2013 Cresset Group Ltd.
Conclusions
> Work in progress > Full similarity matrix shows potential of 3D sim to add value > Full matrix difficult to handle and possibly unnecessary > Using probes looks like a possible solution
> But how many – 100 arbitrary? Should they be field diverse?
> PMI – binned by mwt?
> Not a panacea - still need to play the numbers game > All methods have bias – strongly field distinct compounds are
discriminated well but…the rest? > Major issue not enough breadth to sample conformations
© 2013 Cresset Group Ltd.
> We have excellent software > An excellent team of modellers > We are extremely flexible > We can deliver on diverse projects > Integrity
> If we don’t think we can help you we wont try and sell you a solution we don’t believe in
Conclusions – comp. chem. solutions
© 2013 Cresset Group Ltd.
Acknowledgements
> Cresset > Tim Cheeseright
> Rob Scoffin
> Mark Mackey
> James Melville
> Mission Therapeutics > Keith Menear, Mark Kemp