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AZD9833

AstraZeneca · Phase 3 active Small molecule

AZD9833 is an oral selective estrogen receptor degrader (SERD) that binds to and degrades the estrogen receptor, blocking estrogen-driven cancer cell growth.

AZD9833 is an oral selective estrogen receptor degrader (SERD) that binds to and degrades the estrogen receptor, blocking estrogen-driven cancer cell growth. Used for Hormone receptor-positive, HER2-negative advanced or metastatic breast cancer, Hormone receptor-positive breast cancer in combination with CDK4/6 inhibitors.

At a glance

Generic nameAZD9833
SponsorAstraZeneca
Drug classSelective Estrogen Receptor Degrader (SERD)
TargetEstrogen Receptor Alpha (ESR1)
ModalitySmall molecule
Therapeutic areaOncology
PhasePhase 3

Mechanism of action

AZD9833 functions as a next-generation SERD that achieves rapid and sustained degradation of estrogen receptor alpha in hormone receptor-positive breast cancer cells. Unlike traditional selective estrogen receptor modulators (SERMs), SERDs eliminate the receptor protein entirely rather than simply blocking its activity, preventing both ligand-dependent and ligand-independent signaling. This mechanism overcomes some resistance mechanisms seen with aromatase inhibitors and tamoxifen.

Approved indications

Common side effects

Key clinical trials

Primary sources

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SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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