Defining response is key to de-escalation
In the IMpassion031 trial, “what we saw is a tendency to better outcomes for those patients who received atezolizumab,” said Matteo Lambertini, MD, of the University of Genova (Italy), who served as discussant for the two studies. The IMpassion031 study raises the question of where we are in the use of immuno-oncology for eTNBC. The study is now one of five neoadjuvant trials in this population.
Dr. Lambertini cited the KEYNOTE-522 study, which showed significant results in EFS. However, sample sizes and statistical design were different between these studies. “I think we need large studies of data in the adjuvant and postneoadjuvant setting for patients with triple-negative breast cancer.”
Postneoadjuvant considerations from the IMpassion031 trial showed good outcomes with no additional benefit of an immune checkpoint inhibitors.
For those patients with a pCR, it is definitely time to de-escalate treatment,” he said. In patients without pCR, escalation is needed, but an improved definition of pCR is also needed.
With regard to the ATHENE study, “it may be considered a positive study because the threshold of 40% was reached,” he said. The question is what is the optimum chemotherapy backbone. There appears to be no added benefit to adding an immune checkpoint inhibitor.
There are needs for defining the role of immunotherapy in HER2-positive breast cancer and more biomarker research to inform patient selection and study design, he said.
Finally, “I am not sure that the addition of an immune checkpoint inhibitor can be considered a de-escalation,” he noted.
IMpassion031 was supported by F. Hoffmann–La Roche. Dr. Barrio disclosed financial relationships with numerous companies. ABSCG-52/ATHENE was supported by the Austrian Breast and Colorectal Cancer Study Group and Roche Austria. Dr. Rinnerthaler disclosed relationships with multiple companies including Amgen, Daiichi Sankyo, Lilly, Gilead, MSD, Novartis, Pfizer, Roche, Seagen, and Pierre Fabre. Dr. Lambertini disclosed relationships with multiple companies including Roche, Novartis, AstraZeneca, Lilly, Exact Sciences, Pfizer, MSD, Seagen, Gilead, Takeda, Sandoz, Ipsen, Libbs, Knight, and Daiichi Sankyo.