XCancer

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

Description:

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. Focusing on a central visual "patient-based" classification that captures the entire disease burden, a side-by-side display will be used, comparing baseline FDG-PET/CT (which identifies all FDG-positive metastases regardless of their HER2-imaging status) and HER2-PET/CT. Subjects will be categorized into two HER2-PET/CT patterns (positive vs. negative) based on proportion of FDG-avid tumor load with significant 89Zr-trastuzumab uptake. Subjects classified as "positive" 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. FDG-PET/CT will be performed before cycle 2 of T-DM1 will serve as a research tool to correlate metabolic changes with clinical outcomes. Other FDG-PET/CT will be performed before cycle 4 of T-DM1 for assessment of response. Subjects who demonstrate a partial or complete response (responders) will continue treatment with T-DM1. Subjects who exhibit stable disease or disease progression (non-responders) will discontinue study treatment and enter the survival follow-up period. For responders, subsequent metabolic evaluations will be performed every 3 months, with FDG-PET/CT. Treatment response will be assessed according to metabolic response. For these subjects, mandatory blood samples will be obtained at all metabolic reassessments. Subjects with HER2-PET/CT classified as "negative" will receive treatment of physician's choice (TPC) as per the best local clinical practice and be out of the study. All enrolled subjects will undergo a mandatory biopsy during the pre-treatment period. 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.

Sponsor:

Jules Bordet Institute

Phase:

Phase 2

Contacts:

Martine Piccart, Md, PhD (STUDY_CHAIR)

Margot Morelle (CONTACT)

zephir02.ctsu@hubruxelles.be

+3225413976

Ikram El Idrissi (CONTACT)

zephir02.ctsu@hubruxelles.be

+3225413081

Government Study Link:

NCT06595563 - Click here to see study on

ClinicalTrials.gov

FDG

Isotope(s):
Target(s):
  • Glucose Transport
Ligand Class: Small Molecules

trastuzumab

Isotope(s):
Target(s):
  • HER2
Ligand Class: Antibodies
Chelator: DFO
Inclusion
  • Adequate Liver Function, including all the following parameters:
  • Multifocal unilateral or bilateral breast adenocarcinoma tumours are allowed if all tested HER2-positive, according to local testing
  • Must have histologically or cytologically confirmed progressive advanced/metastatic HER2-positive breast carcinoma as per the updated American Society of Clinical Oncology (ASCO) - College of American Pathologists (CAP) guidelines according to local testing. HER2 status may be determined in the primary breast cancer tumour or, when not available, in a metastatic lesion.
  • At screening FDG-PET at least two "target" lesions are required to fulfil the following criteria: (1) anatomically transaxial diameter ≥ 1.5 cm and (2) metabolically assessable with a maximum standard uptake value corrected for lean body mass (SUVmax) ≥ 1.5 x SUVmean + 2 standard deviations (SD) of the liver measured in a 3-cm-diameter spherical volume of interest (VOI) in normal liver parenchyma.In case of suspected liver metastasis, a lesion should have a SUVmax ≥ 2 x SUVmean + 3 SD of the blood pool measured in a 1 cm-diameter VOI within descending thoracic aorta. Lesions pre-treated with irradiation are not eligible for consideration as "target" lesions.
  • Prior treatment with taxane, trastuzumab and pertuzumab (early or advanced setting) and T-DXd (metastatic setting). In order to be eligible, patients subjects must have received T-DXd as the last systemic metastatic treatment line before inclusion, and presented disease progression on this drug.Prior therapy with tucatinib, trastuzumab, and capecitabine, in advanced setting, is permissible, provided that T-DXd serves as the last systemic metastatic treatment line before inclusion, and patient subject presented disease progression on this drug.
Exclusion
  • Brain metastasis as sole metastasis and/or symptomatic or requiring therapy to control symptoms.
  • Requirement for continuous oxygen therapy