We spoke with Dr. Leisha Emens, PhD, at the European Society for Medical Oncology Congress 2019, held in Barcelona, Spain from September 27, 2019 to October 1, 2019. Dr. Emens shared her thoughts on overall survival in the phase II KATE2 study. KATE2 is the study of the PDL-1 inhibitor atezolizumab (Tecentriq) and T-DM1(Kadcyla) vs a placebo and T-DM1 in previously treated HER2-positive advanced breast cancer.
"Currently, there is a large effort to develop effective immunotherapy combinations that can enhance the activity of single agent PD-1 or PDL-1 blockade. HER2-positive breast cancer is unique in that there are a number of HER2-targeted agents that could potentially be combined with immune checkpoint blockade. The main ones include trastuzamab and trastuzamab emtansine, an antibody-drug conjugate. Both of those have, as a backbone, the trastuzamab antibody which in and of itself has immune-modulating activity. The antibody drug conjugate also has a chemotherapeutic agent conjugated directly to the antibody and that could also potentially have immune-modulating activity.
So, the rationale underlining KATE2, which is a phase II randomized trial that explored the clinical activity of adding atezolizumab to TDM1, is that combining these 2 agents maybe additive or even synergistic relative to the clinical activity of the single agents alone."