8EXV image
Entry Detail
PDB ID:
8EXV
Keywords:
Title:
Crystal structure of PI3K-alpha in complex with compound 32
Biological Source:
Source Organism:
Host Organism:
PDB Version:
Deposition Date:
2022-10-25
Release Date:
2022-11-30
Method Details:
Experimental Method:
Resolution:
2.48 Å
R-Value Free:
0.25
R-Value Work:
0.20
R-Value Observed:
0.20
Space Group:
P 21 21 21
Macromolecular Entities
Polymer Type:polypeptide(L)
Description:Phosphatidylinositol 4,5-bisphosphate 3-kinase catalytic subunit alpha isoform
Chain IDs:A
Chain Length:1080
Number of Molecules:1
Biological Source:Homo sapiens
Ligand Molecules
Primary Citation

Abstact

Small molecule inhibitors that target the phosphatidylinositol 3-kinase (PI3K) signaling pathway have received significant interest for the treatment of cancers. The class I isoform PI3Kα is most commonly associated with solid tumors via gene amplification or activating mutations. However, inhibitors demonstrating both PI3K isoform and mutant specificity have remained elusive. Herein, we describe the optimization and characterization of a series of benzoxazepin-oxazolidinone ATP-competitive inhibitors of PI3Kα which also induce the selective degradation of the mutant p110α protein, the catalytic subunit of PI3Kα. Structure-based design informed isoform-specific interactions within the binding site, leading to potent inhibitors with greater than 300-fold selectivity over the other Class I PI3K isoforms. Further optimization of pharmacokinetic properties led to excellent in vivo exposure and efficacy and the identification of clinical candidate GDC-0077 (inavolisib, 32), which is now under evaluation in a Phase III clinical trial as a treatment for patients with PIK3CA-mutant breast cancer.

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Primary Citation of related structures