Trastuzumab Deruxtecan in First-line HER2-positive Locally Advanced/MBC Patients Resistant to Trastuzumab+Pertuzumab

Exclusion criteria

• ✕. Prior chemotherapy or HER2-targeted therapy for locally advanced or MBC (one prior endocrine therapy regimen for MBC without concurrent anti-HER2 therapy or radiotherapy is allowed).
• ✕. Ineligible for treatment with T-DXd.
• ✕. Any substance abuse or other medical conditions that, in the investigator's opinion, may interfere with patient's participation or study results.
• ✕. Patients with spinal cord compression, leptomeningeal disease or clinically active central nervous system (CNS) metastases. Participants with clinically inactive brain metastases or treated brain metastases that are no longer symptomatic, and no needing corticosteroids or anticonvulsants may be enrolled in the study.
• ✕. Active or prior documented interstitial lung disease (ILD)/pneumonitis or suspected ILD/pneumonitis that cannot be ruled out by imaging at screening.
• ✕. Lung criteria:
• ✕. Lung-specific intercurrent clinically significant illnesses including, but not limited to, any underlying pulmonary disorder (e.g. pulmonary emboli within three months of the study enrollment, severe asthma, severe Chronic obstructive pulmonary disease (COPD), restrictive lung disease, pleural effusion etc.).
• ✕. Any autoimmune, connective tissue or inflammatory disorders (e.g. Rheumatoid arthritis, Sjogren's, sarcoidosis etc.) where there is documented, or a suspicion of pulmonary involvement at the time of screening. Full details of the disorder should be recorded in the electronic Case Report Form (eCRF) for patients who are enrolled in the study.