ARV-471 is an investigational targeted protein degrader designed to treat certain types of breast cancer, particularly estrogen receptor-positive (ER+) metastatic breast cancer. It functions by selectively degrading the estrogen receptor, a key driver in the growth of ER+ breast tumors. Unlike traditional hormone therapies that merely block the receptor, ARV-471 tags the receptor for destruction within the cell, potentially offering a more complete suppression of tumor growth signals. This mechanism may be effective in patients who have developed resistance to standard endocrine therapies, including those with ESR1 mutations commonly associated with disease progression. Clinical trials are evaluating its efficacy both as a monotherapy and in combination with other agents like CDK4/6 inhibitors, aiming to improve outcomes for patients with advanced disease. Due to its targeted approach and favorable early safety profile, ARV-471 represents a promising next-generation therapy in the evolving landscape of breast cancer treatment.