Not yet recruiting

ImmunoPET with 89Zr‑trastuzumab to predict response to trastuzumab deruxtecan in patients with locally advanced or metastatic breast cancer

InvestigationalNo placebo

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

A plain-language summary of the goals, design and what participants do

A group of patients with confirmed breast cancer that has spread locally or to distant sites will receive an antibody‑drug conjugate called Trastuzumab Deruxtecan. Before starting this therapy, a small amount of a specially labeled antibody, identified as 89Zr‑Trastuzumab, will be given by injection to allow a picture of the tumor to be taken with a scanning technique.

The study’s purpose is to find out whether the picture obtained with the labeled antibody together with an early FDG PET/CT scan can predict how the cancer will respond to the antibody‑drug treatment after a few cycles. After the injection of the imaging agent, participants will have a scan using PET technology, then begin the standard course of the antibody‑drug. Additional scans will be performed after three treatment cycles and later in the follow‑up period to see how the disease is behaving.

Response will be checked by looking at changes in tumor activity on the PET images, called a metabolic response, and by measuring tumor size on standard pictures taken with CT or MRI, referred to as a radiological response. The study will also record how long patients go without the disease getting worse (progression‑free survival) and how long they live overall (overall survival). These measurements help researchers understand whether the early imaging can be a useful tool for guiding treatment decisions.

The research process

The trial runs in 8 steps – from screening to follow-up. Each step says what happens and what the team monitors.

Step 1
Initial imaging injection
After joining the study, receive a single intravenous injection of 89zr-trastuzumab. the dose is 37 mbq, administered as a solution for injection.
The injection is performed by a qualified health professional in a clinical setting.
Step 2
Baseline pet/ct scan
Within a few days of the injection, undergo a combined pet/ct scan. this imaging exam visualizes how the tracer distributes in the body and provides a baseline picture of the tumour activity.
Step 3
Start of antibody‑drug conjugate therapy
Begin treatment with trastuzumab deruxtecan (t‑dxd), an antibody‑drug conjugate approved for breast cancer. the medication is given intravenously according to the standard dosing schedule used in routine care.
T‑dxd is administered in repeated cycles; each cycle follows the timing recommended by the treating physician.
Step 4
Treatment cycles
Receive at least three consecutive cycles of trastuzumab deruxtecan. each cycle consists of one intravenous infusion, after which routine clinical monitoring is performed.
The interval between cycles follows the standard practice (typically several weeks), but exact timing is determined by the treating physician.
Step 5
Mid‑treatment pet/ct assessment
After completing three cycles of trastuzumab deruxtecan, undergo a second pet/ct scan to evaluate the metabolic response of the tumours.
The scan is compared with the baseline images to determine whether a complete or partial metabolic response has occurred.
Step 6
Six‑month follow‑up imaging
Approximately six months after the start of therapy, a third pet/ct scan may be performed to assess longer‑term metabolic response.
This imaging helps to confirm whether the tumour activity remains reduced.
Step 7
Radiological evaluations
Standard radiological imaging (such as ct or mri) is performed after three cycles and again at six months to evaluate the anatomical response of the tumours.
These assessments follow the criteria used in routine practice to classify complete or partial radiological responses.
Step 8
Long‑term follow‑up
Periodic clinical visits and imaging may continue for the duration of the study to monitor progression‑free survival, overall survival, and any new brain metastases that could be detected by 89zr-trastuzumab PET or standard brain imaging.

Who can join the trial?

6 criteria

Written informed consent: You must sign a consent form before any study procedures. If you cannot sign yourself, a trusted person you choose can sign for you.
You must already be enrolled in the OASIS study (the ongoing research group that is collecting data for this trial).
You must have locally advanced or metastatic breast cancer and be eligible to receive the medication Trastuzumab Deruxtecan (T‑Dxd) as part of your regular treatment.
At the start of the study, imaging (scans) must show at least two target lesions that meet two conditions:
- Each lesion is at least 1.5 cm in size and can be measured according to RECIST 1.1 (a standard set of rules doctors use to measure tumor size).
- Each lesion can be measured for activity using a PET scan, with a value called SUVmax (the highest uptake of the tracer) that is at least 1.5 times the average liver uptake plus two standard deviations. This means the lesion shows enough activity to be clearly seen on the scan.
- You must be willing and able to follow all study instructions and attend all required visits for the entire duration of the trial.

Who cannot join the trial?

6 criteria

Male patients cannot join the study because the trial is intended only for people assigned female at birth.
Anyone who has already received the study drug Trastuzumab deruxtecan (T‑DXd) is excluded, since the research is looking at the first use of this medication.
People who have a hypersensitivity (an allergic reaction) to the injection of the imaging substance called ImmunoPET radioligands cannot participate. ImmunoPET radioligands are tiny amounts of a radioactive material used to take special pictures of the tumor.
Individuals who are claustrophobic (fearful of small, enclosed spaces) or who cannot stay still for about 30 minutes are excluded, because the imaging scan requires the person to remain motion‑free.
Women who are pregnant, breastfeeding, or planning to become pregnant during the study or within 90 days after the last dose cannot take part, to protect the baby from any possible effects of the treatment.
People who are deprived of their liberty (e.g., in jail), under protective custody, or have a legal guardian are not eligible to enroll.

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not yet recruiting

Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

89Zr‑Trastuzumab is a special form of the breast‑cancer drug trastuzumab that has been attached to a tiny amount of a radioactive substance called zirconium‑89. It is given through an IV and then scanned with a PET camera. The radiation lets doctors see where the drug goes in the body and how much HER2‑positive cancer is present. In this study, the images from this scan are used to help predict how well patients will respond to the standard antibody‑drug treatment (T‑DXd) after a few cycles. The test is only for imaging and does not treat the cancer itself.

What is already known about the treatment

89Zr-Trastuzumab_IJB - The medication is given by intravenous injection as a sterile solution for injection, typically delivering a dose of 37 MBq of the radiolabeled antibody. It is an investigational diagnostic agent currently being studied in clinical trials and is not yet approved for routine medical use. The test is used to image HER2‑positive breast cancer patients who may later receive the antibody‑drug conjugate Trastuzumab Deruxtecan. The drug works by the antibody part (trastuzumab) binding to the HER2 protein on cancer cells, while the attached zirconium‑89 emits signals that a PET scanner can detect, and it is classified as a HER2‑targeted radiopharmaceutical for PET imaging.

Investigated diseases

HER2‑positive locally advanced or metastatic breast cancer - This is a form of breast cancer that produces high levels of the HER2 protein, which helps the tumor grow. In the locally advanced stage, the tumor has grown large or spread to nearby tissues and lymph nodes. When it becomes metastatic, cancer cells travel through the bloodstream or lymph system to distant organs such as bone, liver, lung, or brain. The disease typically progresses by increasing in size and establishing new tumor sites over time.