Is Fulvestrant/Fushida a chemotherapy drug or a targeted drug?

Fulvestrant (Fulvestrant) is a selective estrogen receptor degrader (SERD), mainly used for the treatment of hormone receptor-positive (HR+), HER2-negative advanced or metastatic breast cancer. Many patients confuse the concepts of chemotherapy drugs and targeted drugs, so it is particularly important to understand the pharmacological properties of fulvestrant.

Chemotherapy drugs usually kill tumor cells by directly inhibiting cell division, damagingDNA or affecting cell metabolism. Their effects are broad-spectrum and non-selective, and are often accompanied by systemic side effects such as bone marrow suppression, hair loss, nausea and vomiting. Fulvestrant is different. It competitively binds to estrogen receptors and promotes receptor degradation, thereby blocking the proliferation of estrogen signals in breast cancer cells. This mechanism belongs to targeting the endocrine pathway, so fulvestrant is closer to the category of targeted drugs, but its target is hormone receptors rather than gene mutations or specific enzyme activities.

Clinically, fulvestrant can be used alone or in combination withCDK4/6 inhibitors (such as ribociclib, palbociclib) to enhance the anti-tumor effect. Its targeting is reflected in that it only acts on HR-positive breast cancer cells and has less impact on other types of cells. Therefore, the overall toxic and side effects are lower than traditional chemotherapy. Applications for fulvestrant include newly diagnosed advanced breast cancer, subsequent treatment of disease progression after prior endocrine therapy, and in combination with targeted agents in combination therapy regimens.

In general, fulvestrant is not a classic chemotherapy drug, but a targeted endocrine therapy drug targeting the hormone receptor pathway. It inhibits tumor growth by precisely blocking hormone signals, providing an important treatment option besides chemotherapy, especially suitable for postmenopausal patientsHR-positive breast cancer.

Reference materials:https://medlineplus.gov/druginfo/meds/a607031.html