Question: what are estrogen receptor downregulators?
Answer: Estrogen receptor downregulators, called ERDs for short, block the effects of estrogen in breast tissue. ERDs work in a similar way to SERMs, such as tamoxifen. ERDs sit in the estrogen receptors in breast cells. If an ERD is in the estrogen receptor, there is no room for estrogen and it can't attach to the cell.