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NOLVADEX (tamoxifen)

AstraZeneca · Phase 3 active Small molecule

NOLVADEX (tamoxifen) is a Selective estrogen receptor modulator (SERM) Small molecule drug developed by AstraZeneca. It is currently in Phase 3 development for Metastatic breast cancer (estrogen receptor-positive), Adjuvant treatment of early-stage breast cancer, Breast cancer risk reduction in high-risk women.

Tamoxifen is a selective estrogen receptor modulator (SERM) that blocks estrogen signaling in breast tissue by competitively binding to estrogen receptors.

Tamoxifen is a selective estrogen receptor modulator (SERM) that blocks estrogen signaling in breast tissue by competitively binding to estrogen receptors. Used for Metastatic breast cancer (estrogen receptor-positive), Adjuvant treatment of early-stage breast cancer, Breast cancer risk reduction in high-risk women.

At a glance

Generic nameNOLVADEX (tamoxifen)
SponsorAstraZeneca
Drug classSelective estrogen receptor modulator (SERM)
TargetEstrogen receptor alpha (ERα)
ModalitySmall molecule
Therapeutic areaOncology
PhasePhase 3

Mechanism of action

Tamoxifen acts as an antagonist at estrogen receptors in breast cancer cells, preventing estrogen-driven proliferation. In other tissues such as bone and endometrium, it can exhibit partial agonist activity. This selective modulation makes it effective for both treatment and prevention of estrogen receptor-positive breast 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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Frequently asked questions about NOLVADEX (tamoxifen)

What is NOLVADEX (tamoxifen)?

NOLVADEX (tamoxifen) is a Selective estrogen receptor modulator (SERM) drug developed by AstraZeneca, indicated for Metastatic breast cancer (estrogen receptor-positive), Adjuvant treatment of early-stage breast cancer, Breast cancer risk reduction in high-risk women.

How does NOLVADEX (tamoxifen) work?

Tamoxifen is a selective estrogen receptor modulator (SERM) that blocks estrogen signaling in breast tissue by competitively binding to estrogen receptors.

What is NOLVADEX (tamoxifen) used for?

NOLVADEX (tamoxifen) is indicated for Metastatic breast cancer (estrogen receptor-positive), Adjuvant treatment of early-stage breast cancer, Breast cancer risk reduction in high-risk women.

Who makes NOLVADEX (tamoxifen)?

NOLVADEX (tamoxifen) is developed by AstraZeneca (see full AstraZeneca pipeline at /company/astrazeneca).

What drug class is NOLVADEX (tamoxifen) in?

NOLVADEX (tamoxifen) belongs to the Selective estrogen receptor modulator (SERM) class. See all Selective estrogen receptor modulator (SERM) drugs at /class/selective-estrogen-receptor-modulator-serm.

What development phase is NOLVADEX (tamoxifen) in?

NOLVADEX (tamoxifen) is in Phase 3.

What are the side effects of NOLVADEX (tamoxifen)?

Common side effects of NOLVADEX (tamoxifen) include Hot flashes, Vaginal discharge, Nausea, Vaginal bleeding, Endometrial cancer (rare), Thromboembolic events.

What does NOLVADEX (tamoxifen) target?

NOLVADEX (tamoxifen) targets Estrogen receptor alpha (ERα) and is a Selective estrogen receptor modulator (SERM).

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