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Tamoxifen (Nolvadex)

AstraZeneca · Phase 3 active Small molecule

Tamoxifen acts as a selective estrogen receptor modulator (SERM) to inhibit estrogen's action on breast cancer cells.

Tamoxifen acts as a selective estrogen receptor modulator (SERM) to inhibit estrogen's action on breast cancer cells. Used for Adjuvant treatment of breast cancer in postmenopausal women with estrogen receptor-positive disease, Treatment of metastatic breast cancer in postmenopausal women with estrogen receptor-positive disease.

At a glance

Generic nameTamoxifen (Nolvadex)
Also known asNolvadex
SponsorAstraZeneca
Drug classSelective estrogen receptor modulator (SERM)
TargetEstrogen receptor
ModalitySmall molecule
Therapeutic areaOncology
PhasePhase 3

Mechanism of action

By binding to estrogen receptors, tamoxifen blocks estrogen's ability to promote the growth of estrogen receptor-positive breast cancer cells. This leads to a reduction in tumor size and slowing of disease progression. Additionally, tamoxifen has been shown to have some estrogen-agonist effects in other parts of the body, such as the uterus, where it can help prevent cancer.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

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

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