An interview with Dr. Beverly Moy from Massachusetts General Hospital in Boston, MA, lead author on "Chemotherapy and Targeted Therapy for HER2-Negative Metastatic Breast Cancer That is Either Endocrine-Pretreated or Hormone Receptor-Negative: ASCO Guideline Rapid Recommendation Update." Dr. Moy reviews data from the recently published DESTINY-Breast04 study, and the ASCO Expert Panel's updated recommendation on the use of trastuzumab deruxtecan. For more information, visit www.asco.org/breast-cancer-guidelines.   TRANSCRIPT Brittany Harvey: Hello, and welcome to the ASCO Guideline podcast series brought to you by the ASCO podcast network, a collection of nine programs covering a range of educational and scientific content, and offering enriching insight into the world of cancer care. You can find all the shows, including this one, at asco.org/podcasts. My name is Brittany Harvey, and today I’m interviewing Dr. Beverly Moy from Massachusetts General Hospital in Boston, Massachusetts, lead author on 'Chemotherapy and Targeted Therapy for HER2-Negative Metastatic Breast Cancer That is Either Endocrine-Pretreated or Hormone Receptor-Negative: ASCO Guideline Rapid Recommendation Update'. Thank you for being here, Dr. Moy. Dr. Beverly Moy: It’s my pleasure. Thank you for having me. Brittany Harvey: Great. First, I’d like to note that ASCO takes great care in the development of its guidelines and ensuring that the ASCO Conflict of Interest Policy is followed for each guideline. The full conflict of interest information for this guideline panel is available online with the publication of the guideline in the Journal of Clinical Oncology. Dr. Moy, do you have any relevant disclosures that are directly related to this guideline topic? Dr. Beverly Moy: I do not have any relevant disclosures that are directly relevant to this guideline topic. Brittany Harvey: Thank you. Then let’s talk about this rapid update. So first, what prompted a rapid update to this guideline on chemotherapy and targeted therapy for patients with HER2-negative metastatic breast cancer that is either endocrine-pretreated or hormone receptor-negative, which was last updated in 2021? Dr. Beverly Moy: First, I would state that ASCO issues rapid guideline recommendation updates when really important advances in the treatment and management of cancer have been presented. This mechanism really allows clinicians to keep up with the rapid advances in cancer management. The fact that a rapid update had to be issued just one year after the full updated guideline that was published in 2021, as you just mentioned, is really a testament to the advances in cancer research and clinical trials that have been made recently. But I will state that the reason why this rapid update was done was because the result of the DESTINY-Breast04 study were so strong and compelling and showed such a large degree of benefit to a large group of metastatic breast cancer patients that we felt as the guideline panel that this rapid update had to be out there. We really wanted to make sure that the oncology community was aware of these results. That’s based on the strength of the trial. The DESTINY-Breast04 trial was a very large randomized study that showed that trastuzumab deruxtecan significantly improved progression-free survival and overall survival compared to treatment of physician’s choice in patients with metastatic, “HER2-low” breast cancer. Brittany Harvey: So then based off this new data from the DESTINY-Breast04 trial that you just mentioned, what is the updated recommendation from the guideline expert panel? Dr. Beverly Moy: So the updated recommendation is that patients with HER2-low, or to be specific, HER2 IHC1+ or 2+ and ISH negative metastatic breast cancer who have received at least one prior chemotherapy for metastatic disease, if they’re hormone receptor-positive, are refractory to endocrine therapy, those patients should be offered treatment with trastuzumab deruxtecan. Brittany