What is [18F]fluoroestradiol (FES) used for?

[18F]fluoroestradiol (FES) is indicated for Imaging of estrogen receptor-positive tumors.

Who makes [18F]fluoroestradiol (FES)?

[18F]fluoroestradiol (FES) is developed by Asan Medical Center.

What development phase is [18F]fluoroestradiol (FES) in?

[18F]fluoroestradiol (FES) is in Phase 3.

Last reviewed 2026-04-23 · How we verify

[18F]fluoroestradiol (FES)

Asan Medical Center · Phase 3 active Small molecule

FES is a radiolabeled estrogen receptor ligand used for imaging estrogen receptor-positive tumors.

FES is a radiolabeled estrogen receptor ligand used for imaging estrogen receptor-positive tumors. Used for Imaging of estrogen receptor-positive tumors.

At a glance

Generic name	[18F]fluoroestradiol (FES)
Sponsor	Asan Medical Center
Target	estrogen receptor
Modality	Small molecule
Therapeutic area	Oncology
Phase	Phase 3

Mechanism of action

FES binds to estrogen receptors on tumor cells, allowing for visualization of estrogen receptor-positive tumors in the body. This can aid in diagnosis and treatment planning for patients with breast cancer and other estrogen receptor-positive cancers.

Approved indications

Imaging of estrogen receptor-positive tumors

Common side effects

No common side effects on file.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

[18F]fluoroestradiol (FES) CI brief — competitive landscape report
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