HER2 Molecular Imaging With 89Zr-trastuzumab PET/CT as a Predictive Biomarker for Antibody-drug Conjugate Sequencing in Patients With Advanced HER2-positive Breast Cancer

• Status: NOT_YET_RECRUITING
• Trial end date: 2029-09-01

Summary

ZEPHIR-02 is a multicentre, open-label phase II study that will enroll subjects with HER2-positive advanced/metastatic breast cancer (mBC) who have experienced disease progression under trastuzumab deruxtecan (T-DXd) in the metastatic setting.

All subjects will undergo baseline biopsy, blood collection, FDG-PET/CT and 89Zr-trastuzumab PET/CT (HER2-PET/CT) and will be classified as HER2-PET/CT positive or negative, as previously described in the ZEPHIR trial. Subjects classified as "positive" (cohort A) will receive T-DM1 as monotherapy, IV 3.6mg/kg every 3 weeks (21 days +- 3 days) until disease progression, unacceptable toxicity or request of the subject to withdraw from the study. Early FDG PET/CT will be performed before cycle 2 of T-DM1 to assess the response to the treatment. Routine tumour assessments will be performed with FDG-PET/CT until efficacy follow-up is completed. After 2 years of treatment with T-DM1 received by the subject, physician can consider to space the cycles up to 6 weeks.

Subjects classified as HER2-PET/CT negative (cohort B) will receive treatment of physician's choice as per the best local clinical practice.

The study also includes mandatory translational procedures (i.e. collection of tumour biopsy during pre-treatment period and blood samples at pre-specified time points) for exploratory molecular analyses.

• Phase: PHASE2

Details

• Lead Sponsor: Jules Bordet Institute
• Collaborator: Hoffmann-La Roche
• Treatments: Ado-Trastuzumab Emtansine