Is Fulvestrant/Fuxit an endocrine drug?

Fulvestrant (Fulvestrant) is an important endocrine drug, mainly used to treat hormone receptor-positive (ER-positive) breast cancer. There are many types of breast cancer treatments, among which endocrine therapy (hormone therapy) plays a central role in the treatment of hormone receptor-positive breast cancer. Fulvestrant, a selective estrogen receptor modulator (SERM), inhibits the growth and spread of cancer cells by inhibiting the effects of estrogen on breast cancer cells.

The mechanism of action of endocrine therapy drugs is mainly to inhibit the growth of hormone-dependent cancers by regulating hormone levels in the body or preventing the binding of hormones to their receptors. For many breast cancer patients, the growth and spread of cancer cells is affected by the presence of estrogen in the body. After estrogen binds to specific receptors on the surface of cancer cells, it can stimulate the proliferation of cancer cells, so blocking this effect becomes the key to treatment.

The mechanism of action of fulvestrant is different from traditional antiestrogens. Fulvestrant not only competitively binds to estrogen receptors and blocks their effects, but completely inhibits the effects of estrogen by directly degrading the receptors. Unlike other anti-estrogens such as tamoxifen, fulvestrant provides a stronger anti-estrogen effect. It fundamentally prevents cancer cells from responding to estrogen by completely "inactivating" estrogen receptors, so it has certain advantages in combating drug resistance during treatment.

In the treatment of hormone receptor-positive breast cancer, fulvestrant is often used in patients who have not responded to treatment with other endocrine drugs, such as tamoxifen or anastrozole, especially if the cancer has recurred or metastasized. In combination with other drugs, fulvestrant plays an important role in relieving symptoms and prolonging survival.

References: https://medlineplus.gov/druginfo/meds/a607031.html