OASIS-ImmunoPET_Antibody-based PET imaging and treatment response in breast cancer treated with an antibody-drug conjugate according to current standard indications.

Condition studied

Patients with histologically confirmed or radiologically documented locally advanced or metastatic breast cancer who are eligible to receive the antibody-drug conjugate (ADC) Trastuzumab Deruxtecan (T-DXd) according to local approval.

Investigational medicinal product(s)

Eligibility

Primary endpoint

Metabolic objective response rate (ORR) is defined as the proportion of patients who achieved a complete metabolic response (CR) or partial metabolic response (PR) assessed by investigators according to PERCIST 1.0 after 3 cycles of T-DXd.

Endpoint detail

Metabolic ORR at 6 months is defined as the proportion of patients who achieved a metabolic CR or PR assessed by investigators according to PERCIST 1.0 at 6 months from treatment initiation., Radiological ORR is defined as the proportion of patients who achieved a confirmed complete radiological response (CR) or partial radiological response (PR) assessed by investigators according to RECIST 1.1 after 3 cycles and 6 months of treatment initiation., Progression-Free Survival (PFS) is defined as the time from treatment initiation to the first documented radiological or metabolic progression of disease or death, whatever the cause. Patients still alive at the cut-off time without documented progression (including lost to follow-up) will be censored at the time of the latest evaluable efficacy assessment., Radiological PFS defined as Time from treatment initiation to the first documented radiological or progression of disease or death, whatever the cause., Overall Survival (OS) is defined as the time from inclusion to death due to any cause. Patients still alive at the cut-off time (including lost to follow-up) will be censored at the last known alive date, Time to detection of brain metastases as identified by [⁸⁹Zr]-Trastuzumab PET vs standard modality (brain CT/MRI, patients’ symptoms, clinical examen: presence of new or progressive lesions in the brain, confirmed by radiological imaging. Detection is considered the first instance in which metastases are identified through either [⁸⁹Zr]-Trastuzumab PET or standard modality (brain CT/MRI, patients’ symptoms, clinical examen)., Proportion of patients with change in the pattern from baseline to progression or end of treatment. A positive pattern means that the entire or majority of the tumour load shows significant tracer uptake, whereas a negative pattern means the dominant part or all of the tumour load lacks significant tracer uptake.