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Tamoxifen, Letrozole, Anastrozole or Exemestane

Institut Claudius Regaud · FDA-approved active Small molecule

Tamoxifen, Letrozole, Anastrozole or Exemestane is a Estrogen receptor antagonist (tamoxifen); Aromatase inhibitor (letrozole, anastrozole, exemestane) Small molecule drug developed by Institut Claudius Regaud. It is currently FDA-approved for Hormone receptor-positive breast cancer, adjuvant treatment, Hormone receptor-positive breast cancer, metastatic, Breast cancer prevention in high-risk women (tamoxifen).

These drugs block estrogen signaling in breast cancer cells, either by directly antagonizing the estrogen receptor (tamoxifen) or by inhibiting aromatase to reduce estrogen production (letrozole, anastrozole, exemestane).

These drugs block estrogen signaling in breast cancer cells, either by directly antagonizing the estrogen receptor (tamoxifen) or by inhibiting aromatase to reduce estrogen production (letrozole, anastrozole, exemestane). Used for Hormone receptor-positive breast cancer, adjuvant treatment, Hormone receptor-positive breast cancer, metastatic, Breast cancer prevention in high-risk women (tamoxifen).

At a glance

Generic nameTamoxifen, Letrozole, Anastrozole or Exemestane
SponsorInstitut Claudius Regaud
Drug classEstrogen receptor antagonist (tamoxifen); Aromatase inhibitor (letrozole, anastrozole, exemestane)
TargetEstrogen receptor alpha (tamoxifen); Aromatase/CYP19A1 (letrozole, anastrozole, exemestane)
ModalitySmall molecule
Therapeutic areaOncology
PhaseFDA-approved

Mechanism of action

Tamoxifen is a selective estrogen receptor modulator that competitively binds to estrogen receptors on hormone-responsive breast cancer cells, blocking estrogen-driven proliferation. Letrozole, anastrozole, and exemestane are aromatase inhibitors that suppress conversion of androgens to estrogen in postmenopausal women, thereby reducing circulating estrogen levels and tumor growth. These mechanisms are effective in estrogen receptor-positive breast cancers.

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

Competitive intelligence

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Frequently asked questions about Tamoxifen, Letrozole, Anastrozole or Exemestane

What is Tamoxifen, Letrozole, Anastrozole or Exemestane?

Tamoxifen, Letrozole, Anastrozole or Exemestane is a Estrogen receptor antagonist (tamoxifen); Aromatase inhibitor (letrozole, anastrozole, exemestane) drug developed by Institut Claudius Regaud, indicated for Hormone receptor-positive breast cancer, adjuvant treatment, Hormone receptor-positive breast cancer, metastatic, Breast cancer prevention in high-risk women (tamoxifen).

How does Tamoxifen, Letrozole, Anastrozole or Exemestane work?

These drugs block estrogen signaling in breast cancer cells, either by directly antagonizing the estrogen receptor (tamoxifen) or by inhibiting aromatase to reduce estrogen production (letrozole, anastrozole, exemestane).

What is Tamoxifen, Letrozole, Anastrozole or Exemestane used for?

Tamoxifen, Letrozole, Anastrozole or Exemestane is indicated for Hormone receptor-positive breast cancer, adjuvant treatment, Hormone receptor-positive breast cancer, metastatic, Breast cancer prevention in high-risk women (tamoxifen).

Who makes Tamoxifen, Letrozole, Anastrozole or Exemestane?

Tamoxifen, Letrozole, Anastrozole or Exemestane is developed and marketed by Institut Claudius Regaud (see full Institut Claudius Regaud pipeline at /company/institut-claudius-regaud).

What drug class is Tamoxifen, Letrozole, Anastrozole or Exemestane in?

Tamoxifen, Letrozole, Anastrozole or Exemestane belongs to the Estrogen receptor antagonist (tamoxifen); Aromatase inhibitor (letrozole, anastrozole, exemestane) class. See all Estrogen receptor antagonist (tamoxifen); Aromatase inhibitor (letrozole, anastrozole, exemestane) drugs at /class/estrogen-receptor-antagonist-tamoxifen-aromatase-inhibitor-letrozole-anastrozole-exemestane.

What development phase is Tamoxifen, Letrozole, Anastrozole or Exemestane in?

Tamoxifen, Letrozole, Anastrozole or Exemestane is FDA-approved (marketed).

What are the side effects of Tamoxifen, Letrozole, Anastrozole or Exemestane?

Common side effects of Tamoxifen, Letrozole, Anastrozole or Exemestane include Hot flashes, Vaginal dryness or discharge, Arthralgia/myalgia, Fatigue, Nausea, Thromboembolic events (tamoxifen).

What does Tamoxifen, Letrozole, Anastrozole or Exemestane target?

Tamoxifen, Letrozole, Anastrozole or Exemestane targets Estrogen receptor alpha (tamoxifen); Aromatase/CYP19A1 (letrozole, anastrozole, exemestane) and is a Estrogen receptor antagonist (tamoxifen); Aromatase inhibitor (letrozole, anastrozole, exemestane).

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