Dr Chen on the Investigation of CDK4/6 Inhibitors in Early-Stage Breast Cancer

Nan Chen, MD, assistant professor, medicine, hematology and oncology (cancer), University of Chicago, UChicago Medicine, discusses the investigation of CDK4/6 inhibitors in patients with early-stage breast cancer.

At an OncLive® State of the Science Summit™ on breast cancer, Chen says she primarily focused on CDK4/6 inhibitors in breast cancer, as well as treatment developments beyond CDK4/6 inhibitors concerning other endocrine agents in estrogen receptor–positive breast cancer. Over the past few years, there have been significant changes in breast cancer treatment, particularly with the incorporation of CDK4/6 inhibitors into the early-stage breast cancer treatment arena, she says. These inhibitors are increasingly used for high-risk patients, reflecting a shift in treatment paradigms aimed at optimizing patient outcomes, Chen explains. Moreover, in the metastatic setting, the FDA approvals of several new agents in recent years has prompted clinicians to carefully evaluate trial data and contextual factors to determine the most suitable treatment options for their patients, she adds.

CDK4/6 inhibitors have become a standard of care in breast cancer treatment over the past decade, and their widespread adoption in clinical practice is evident, Chen continues. Additionally, in the metastatic setting, the proven progression-free survival benefits of CDK4/6 inhibitors are well established, and ribociclib (Kisqali) elicits an overall survival advantage in this patient population, she says. Notably, the phase 3 SONIA trial (NCT03425838) trial investigated the use of CDK4/6 inhibitors in combination with either an androgen inhibitor in the first-line setting or fulvestrant (Faslodex) in the second-line setting in patients with hormone receptor–positive advanced breast cancer, Chen reports. This trial provided valuable insights into patient-specific considerations, indicating potential benefits in terms of reduced toxicities when using CDK4/6 inhibitors in the second-line setting, according to Chen.

As new agents and treatment approaches continue to emerge, the optimization of breast cancer treatment will rely on a comprehensive understanding of the efficacy, safety, and patient-specific considerations associated with each therapeutic option, Chen concludes.