<prompt> All of the following statements about Selective Estrogen Receptor Downregulator SERD, Fulvestrant are true, ExceptIt is a selective estrogen antagonistUsed in the treatment of breast cancerSlower acting, safer and less effective than SERMMay be administered as once a month dose  <response>: Ans is c i.e. Slower acting, safer and less effective than SERM Fulvestrant It is a selective estrogen receptor downregulator SERD or pure antiestrogenpure estrogen antagonist. o Fulverstrant is thought to have an improved safety profile, faster onset and longer duration of action than the SERMs due to its pure ER antagonistic activity. o Fulvestrant is used to treat post menopausal women with metastatic breast cancer that expresses the estrogen receptor hormone receptor positive and is used when first line treatments e.g. tamoxifen or an aromatase inhibitor have failed. Therapeutic uses o Fulverstrant typically is administered as a 250-gm intramuscular injection of monthly intervals. o It is used in post-menopausal women as antiestrogen theraphy of hormone receptor -- positive metastatic breast cancer after progression on first - line antiestrogen theraphy such as tamoxifen or aromatase inhibitors. 