Last reviewed 2026-04-22 · How we verify

CKD-331

CKD-331 is a selective estrogen receptor degrader (SERD) that binds to and degrades estrogen receptors, blocking estrogen-dependent signaling in hormone-sensitive cancers.

CKD-331 is a selective estrogen receptor degrader (SERD) that binds to and degrades estrogen receptors, blocking estrogen-dependent signaling in hormone-sensitive cancers. Used for Hormone receptor-positive, HER2-negative advanced or metastatic breast cancer.

At a glance

Mechanism of action

CKD-331 functions as a SERD by binding to the estrogen receptor with high affinity and promoting its proteasomal degradation, thereby eliminating both ligand-dependent and ligand-independent estrogen receptor signaling. This mechanism differs from selective estrogen receptor modulators (SERMs) by achieving complete receptor elimination rather than partial antagonism. The drug is designed to overcome resistance mechanisms that develop with standard endocrine therapies in hormone receptor-positive breast cancer.

Approved indications

• Hormone receptor-positive, HER2-negative advanced or metastatic breast cancer

Common side effects

• Hot flashes
• Nausea
• Fatigue
• Vaginal dryness

Key clinical trials

• A Clinical Trial to Compare and Evaluate the Safety and Pharmacokinetics of CKD-391(2) (PHASE1)
• A Clinical Trial to Compare and Evaluate the Safety and Pharmacokinetics of CKD-391 (PHASE1)
• Study to Evaluate the Safety and Pharmacokinetics of CKD-331 (PHASE1)
• A Clinical Trial to Evaluate the Efficacy and Safety of CKD-391 and CKD-331 in Patients With Primary Hypercholesterolemia (PHASE3)

Primary sources

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