Hiroji Iwata, MD, PhD
Long-term findings from a phase I study of trastuzumab deruxtecan (DS-8201a) showed that the investigational HER2-targeting antibody-drug conjugate had antitumor activity in multiple tumor types that expressed HER2 at varying levels. Lead author Hiroji Iwata, MD, PhD, said that the activity observed with DS-8201a may shift the definition of HER2expression in cancer.
, Iwata, vice director and chief of Breast Oncology at Aichi Cancer Center Hospital, discussed the promise of DS-8201a in breast cancer or other solid tumors with HER2 expression.
OncLive: Can you provide some background on DS-8201a?
: The HER2-positive population is sensitive to anti-HER2 therapies, and the activity is very promising in metastatic breast cancer. However, the HER2/low breast cancer population does not show as promising of results when using these anti-HER2 therapies. DS-8201a is a very promising drug, and a competitor to anti-HER2 antibody with a similar molecular payload. The characteristic of DS-8201a that is very promising is the bystander effect. Bystander effect permeates on the membrane, so the result is not only beneficial for HER2-overexpressing patients, but patients who are HER2/low.
The bystander effect is a very promising characteristic. Therefore, it is promising in HER2/neu or HER2-low breast cancer and gastric cancer.
What are the significance of the findings?
These phase I data are not only important for breast and gastric cancer, but also for any other cancer with HER2 overexpression or with a HER2-mutant cohort. Those patients can achieve good results using DS-8201a. The breast and gastric cancer population is a very heavily pretreated one and there is a high response here, which is important.
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