ARV-471 is a novel therapeutic agent primarily developed for the treatment of estrogen receptor-positive (ER+) breast cancer. It functions as a PROTAC (PROteolysis TArgeting Chimera), a class of drugs designed to degrade specific proteins within cells. ARV-471 specifically targets the estrogen receptor for degradation, thereby inhibiting the growth and survival of cancer cells that rely on estrogen signaling. This approach offers a potential advantage over traditional hormone therapies, particularly in cases where resistance to standard treatments has developed. It is currently being evaluated in clinical trials to assess its efficacy and safety in patients with advanced or metastatic ER+ breast cancer, including those with ESR1 mutations. Its unique mechanism of action positions it as a promising option for overcoming resistance and improving outcomes in this patient population.