Dr. Ellis on Adjuvant CDK4/6 Inhibition in HR-Positive Breast Cancer

Matthew J. Ellis, MD, PhD, professor and director, Lester and Sue Smith Breast Center, associate director of precision medicine, Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, discusses adjuvant CDK4/6 inhibition in hormone receptor (HR)-positive breast cancer.

Physicians do not yet know how effective CDK4/6 inhibitors are going to be in the adjuvant setting, only that they will show some degree of efficacy, says Ellis. Ellis notes that no one could have predicted the effectiveness of tamoxifen in the adjuvant setting from the metastatic data. Now, physicians know that it is very effective against micrometastatic disease with lasting survival benefit.

Physicians hope that CDK4/6 inhibitors produce similar responses. Ellis explains that there is good evidence that CDK4/6 inhibitors perturb the immune system in viable ways and may even alter the immunogenicity of estrogen receptor-positive tumors in favor of T-cell responses. Still, physicians have to understand why these drugs eventually fail and how that failure might be avoided with other agents, says Ellis.