CDK4/6 Inhibitors in Early Breast Cancer: Different Trial Results Means Good Science

This transcript has been edited for clarity.

Hi. It's Dr Kathy Miller from Indiana University. I just finished a phenomenal science weekend at the European Society for Medical Oncology (ESMO) virtual congress, and I want to share some of the breast cancer data with you.

I remember being taught early in my career that a hallmark of good science, whether it's conducted in a laboratory or in the clinic, is that it forces you to ask more questions than it answers. And if that is the case, we saw some really good science this weekend. I want to review two sets of studies with you that have seemingly similar study designs but came to dramatically different conclusions.

First, let's think about the cyclin-dependent kinase (CDK) inhibitors in the adjuvant setting.

We saw the results of the PALLAS trialthat studied over 4000 largely stage II and III patients (about 1000 had stage IIA disease, so lymph node–negative patients were allowed to enroll) who were randomized to 2 years of palbociclib or not. It was stopped for futility at the second interim analysis. To be clear, the study was not stopped, but the data monitoring committee suggested that all patients still on palbociclib should stop therapy and enter follow-up.