Clinical Trials Combining Aromatase Inhibitors with Other Targeted Treatments

Abstract

Aromatase inhibitors (AIs) play an important role in the treatment of both early and advanced hormone-receptor positive breast cancer. However, not all patients respond to first-line endocrine treatment due to primary de novo resistance, while others may initially respond but eventually progress with secondary acquired resistance. Strategies combining endocrine therapy with targeted inhibitors of growth factors or cell survival pathways to overcome AI resistance and enhance therapy are currently being investigated. This chapter will outline the clinical trials currently underway and will focus on whether AIs in combination with targeted therapies can translate into clinical benefit. Appropriate trial design and patient selection are important considerations for this approach to be successful. Enriching trial recruitment by molecular profiling of different ER+ subtypes will become increasingly important to maximize additional benefit that these new agents may bring to current AIs for breast cancer.