Rethinking HER2-Positive Breast Cancer Treatment Regimens with T-DXd

Dr. VK Gadi and Dr. Jason Mouabbi examine the potential implications of the DESTINY-Breast09 (DB09) trial, which is reassessing treatment strategies for HER2-positive breast cancer. The Cleopatra regimen, which combines taxane chemotherapy with dual HER2 blockade using trastuzumab and pertuzumab, has been a standard treatment for years. Its distinctive structure involves chemotherapy for the initial six months, succeeded by a maintenance phase.

The DB09 study introduces T-DXd (trastuzumab deruxtecan), an antibody-drug conjugate, to evaluate its efficacy compared to the Cleopatra regimen, aiming to provide targeted chemotherapy to cancer cells while minimizing impact on healthy cells. In contrast to Cleopatra, T-DXd is administered continuously until disease progression, presenting a challenge in maintaining a balance between prolonged treatment and patients’ quality of life.

The physicians also examine the potential impact of the trial outcomes on the discipline. As this field advances with emerging combinations and maintenance therapies, such as CDK4/6 inhibitors and tucatinib, oncologists aim to optimize strategies that enhance efficacy while taking patient quality of life into account.