9TBR | pdb_00009tbr

From KRASG12D to pan-KRAS inhibitors

• PDB DOI: https://doi.org/10.2210/pdb9TBR/pdb

• Classification: SIGNALING PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): Yes 


• Deposited: 2025-11-20 Released: 2026-04-22 
• Deposition Author(s): Cleasby, A., Day, P.
• Funding Organization(s): Not funded

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.65 Å
• R-Value Free: 
  0.212 (Depositor), 0.223 (DCC) 
• R-Value Work: 
  0.177 (Depositor), 0.188 (DCC) 
• R-Value Observed: 
  0.178 (Depositor) 

Literature

From KRAS G12D to Pan-KRAS Inhibitors─A Journey Enabled by Synthetic Innovation and Structure-Based Drug Design.

Ma, X., Sloman, D.L., Henderson, T.J., Bennett, D.J., Chessari, G., Day, P.J., Duggal, R., Edelstein, E., Gathiaka, S., Hoover, A., Howard, S., Kawamura, S., Kobayakawa, Y., Lacey, B.M., Lyons, T.W., Mansueto, M.S., Miller, R., Mizuarai, S., Munsell, E.V., O'Reilly, M., Oshima, T., Otte, R.D., Palani, A., Rees, D.C., Sagara, T., Sather, A., Schopf, P., Shibata, K., Shikata, Y., Solban, N., Venkataraman, S., Su, D., Swaminathan, U., Ye, Y., Stoeck, A., Han, Y.

(2026) J Med Chem 69: 9215-9241

• PubMed: 41954203 
• DOI: https://doi.org/10.1021/acs.jmedchem.5c03662
• Primary Citation Related Structures: 
  9TBM, 9TBR, 9TBW, 9TC0, 9TC2, 9TC5, 9TC6


• PubMed Abstract: 
  

  KRAS, a significant oncology target, has been challenging to develop drugs for until recent discoveries of KRAS ^G12C mutant-specific covalent inhibitors, including MK-1084. This article describes efforts toward the discovery of KRAS ^G12D mutant-specific inhibitors and how synthetic innovations and structure-based drug design were utilized to facilitate the discovery of pan-KRAS inhibitors.

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Organizational Affiliation: 
• Department of Discovery Chemistry, Merck & Co., Inc., 33 Ave. Louis Pasteur, Boston 02215, Massachusetts, United States.
Astex Pharmaceuticals, 436 Cambridge Science Park, Cambridge CB4 0QA, U.K.
Department of Pharmacokinetics, Dynamics, Metabolism and Bioanalytics, Merck & Co., Inc., 33 Ave. Louis Pasteur, Boston 02215, Massachusetts, United States.
Department of Process Research and Development, Merck & Co., Inc., 33 Ave. Louis Pasteur, Boston 02215, Massachusetts, United States.
Computational and Structural Chemistry, Merck & Co., Inc., Boston 02115, Massachusetts, United States.
Discovery and Preclinical Research Division, Taiho Pharmaceutical Co., Ltd., Tsukuba 300-2611, Ibaraki, Japan.
Department of Discovery Quantitative Biosciences, Merck & Co., Inc., 33 Ave. Louis Pasteur, Boston 02215, Massachusetts, United States.
Department of Discovery Pharmaceutical Sciences, Merck & Co., Inc., 33 Ave. Louis Pasteur, Boston 02215, Massachusetts, United States.
Department of Discovery Biology, Merck & Co., Inc., 33 Ave. Louis Pasteur, Boston 02215, Massachusetts, United States.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly Evidence: gel filtration

Macromolecule Content 

• Total Structure Weight: 22.27 kDa 
• Atom Count: 1,600 
• Modeled Residue Count: 170 
• Deposited Residue Count: 187 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Isoform 2B of GTPase KRas	A	187	Homo sapiens	Mutation(s): 4  Gene Names: KRAS, KRAS2, RASK2 EC: 3.6.5.2
UniProt & NIH Common Fund Data Resources
Find proteins for P01116 (Homo sapiens) Explore P01116  Go to UniProtKB:  P01116
PHAROS:  P01116 GTEx:  ENSG00000133703

Small Molecules

Ligands 3 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
A1JU6 (Subject of Investigation/LOI)	D [auth A]	4-[6,8-bis(fluoranyl)-2-[[(2~{R},8~{S})-2-fluoranyl-1,2,3,5,6,7-hexahydropyrrolizin-8-yl]methoxy]-4-[(1~{S},5~{R})-1-methyl-3,8-diazabicyclo[3.2.1]octan-3-yl]quinazolin-7-yl]naphthalen-2-ol C33 H34 F3 N5 O2 ZEFNVSLHYTUOEK-WGOBNMDOSA-N
GDP	B [auth A]	GUANOSINE-5'-DIPHOSPHATE C10 H15 N5 O11 P2 QGWNDRXFNXRZMB-UUOKFMHZSA-N
MG	C [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.65 Å
• R-Value Free:  0.212 (Depositor), 0.223 (DCC) 
• R-Value Work:  0.177 (Depositor), 0.188 (DCC) 
• R-Value Observed: 0.178 (Depositor) 

Space Group: H 3 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 94.683	α = 90
b = 94.683	β = 90
c = 120.648	γ = 120

Software Package:

Software Name	Purpose
REFMAC	refinement
PDB_EXTRACT	data extraction
XDS	data reduction
Aimless	data scaling
REFMAC	phasing

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-04-22 
Deposition Author(s): Cleasby, A., Day, P.

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Funding Organization	Location	Grant Number
Not funded		--

Revision History  

• Version 1.0: 2026-04-22
  Type: Initial release
  
• Version 1.1: 2026-05-06
  Changes: Database references