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Faslodex (fulvestrant)

AstraZeneca · FDA-approved approved Quality 58/100

Faslodex works by binding to and degrading the estrogen receptor, preventing it from promoting the growth of cancer cells.

Faslodex (fulvestrant) is a small molecule estrogen receptor antagonist developed by AstraZeneca, targeting the progesterone receptor. It is used to treat metastatic breast cancer that has progressed after antiestrogen therapy. Faslodex was approved by the FDA in 2002 and is now off-patent with multiple generic manufacturers. The drug has a half-life of 16.0 hours and is administered via injection. As an off-patent medication, Faslodex is widely available in the market.

At a glance

Generic namefulvestrant
SponsorAstraZeneca
Drug classEstrogen Receptor Antagonist [EPC]
TargetProgesterone receptor
Therapeutic areaOncology
PhaseFDA-approved
First approval2002

Mechanism of action

Many breast cancers have estrogen receptors (ER) and the growth of these tumors can be stimulated by estrogen. Fulvestrant is an estrogen receptor antagonist that binds to the estrogen receptor in competitive manner with affinity comparable to that of estradiol and downregulates the ER protein in human breast cancer cells.In vitro studies demonstrated that fulvestrant is reversible inhibitor of the growth of tamoxifen-resistant, as well as estrogen-sensitive human breast cancer (MCF-7) cell lines. In in vivo tumor studies, fulvestrant delayed the establishment of tumors from xenografts of human breast cancer MCF-7 cells in nude mice. Fulvestrant inhibited the growth of established MCF-7 xenografts and of tamoxifen-resistant breast tumor xenografts.Fulvestrant showed no agonist-type effects in in vivo uterotrophic assays in immature or ovariectomized mice and rats. In in vivo studies in immature rats and ovariectomized monkeys, fulvestrant blocked the uterotrop

Approved indications

Common side effects

Key clinical trials

Patents

PatentExpiryType
92719902034-05-17Formulation
98334592034-02-14Formulation
101886632034-02-14Formulation

Primary sources

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

SourceUsed for
FDA labelMechanism, indications, dosing, boxed warnings, drug interactions
ClinicalTrials.govTrial enrolment, design, endpoints, results
FDA Orange BookPatents + exclusivity

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