Trastuzumab Deruxtecan Versus Standard Neoadjuvant Treatment for HER2-positive Breast Cancer

The goal of this clinical trial is to compare trastuzumab deruxtecan (T-DXd) to standard preoperative treatment in patients with non-metastatic HER2-positive breast cancer. The main questions it aims to answer are: * is T-DXd more effective than standard preoperative treatment? * are there markers in the tumor or blood of patients with HER2-positive breast cancer that can help us predict response to treatment? Participants will be divided into two groups, where one group will be treated with three courses of T-DXd and the other group will be treated with three courses standard of care treatment. Thereafter, further treatment will be decided by the tumor's molecular subtype.

NCT Number	NCT05900206
Lead Sponsor	Karolinska University Hospital
Conditions	Breast Cancer
Enrollment	370 participants
Start Date	2023-10-26
Primary Completion	2027-04-30 (estimated)
Study Completion	2032-04-30 (estimated)
Updated on ClinicalTrials.gov	2025-09-02