Using HER2-PET imaging to guide HER2-ADC treatment in metastatic HER2-expressing breast cancer

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a prospective, multi-center, open-label, exploratory diagnostic phase II imaging trial using the HER2-specific PET tracer [68Ga]Ga-ABY-025. Participants undergo a baseline HER2-PET scan and a tumour biopsy, and treatment allocation is determined by HER2 status on PET and biopsy. Patients with HER2-expressing lesions on biopsy (fresh or archived) will be treated with the antibody‑drug conjugate T‑DXd. The study tests whether PET-guided selection improves identification of patients likely to benefit from T‑DXd, aiming to improve responses and reduce unnecessary toxicity.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Female patients age ≥18 years.
* Metastatic or locally advanced breast cancer with disease progression after ≥ 1 line of chemotherapy in the palliative setting, or with disease relapse within six months after completion of (neo-) adjuvant chemotherapy.
* The patient must be able and willing to provide written consent to participate in the study.
* At least one metastatic lesion ≥ 10 mm is available for biopsy

  o Exception can be made when a recent biopsy is available (no more than 12 months old and without exposition to HER2-targeted therapy or local radiotherapy to the specific lesion).
* At least one additional metastatic index lesion ≥ 10 mm for evaluation of treatment effect (according to RECIST v1.1)
* WHO performance status ≤ 2.
* Expected survival \> 12 weeks.
* Contraceptives: Females of child-bearing potential must agree to use adequate contraception prior to study entry, for the duration of the study treatment phase and for six months after the last dose of \[68Ga\]Ga-ABY-025. Examples of contraceptive methods with a failure rate of \< 1% per year include bilateral tubal ligation, male sterilization, established, proper use of hormonal contraceptives that inhibit ovulation, hormone- releasing intrauterine devices (IUDs), and copper IUDs. Periodic abstinence (e.g., calendar, ovulation, symptothermal, or postovulation methods) and withdrawal are not acceptable methods of contraception. Women must refrain from donating eggs during this same period. Should a female become pregnant or suspect she is pregnant while participating in this study, she should inform her study physician immediately. If a female participant is of child-bearing potential (females are considered not of childbearing potential if they are at least one year postmenopausal and/or surgically sterile), she must have a documented negative serum Pregnancy testing prior to each administration of the IMP is obligatory.

Exclusion Criteria:

* Contra-indications for treatment for trastuzumab deruxtecan and inability to undergo this treatment as per local treatment routines.
* A previously documented metastatic tumor biopsy that was HER2-positive (IHC 3+ and/or HER2 gene amplification).
* Other manifest malignancies except for basal cell carcinoma of the skin.
* Inadequate cardiac, renal, bone marrow or liver function
* Patients with increased risk of complications from biopsies, i.e. increased risk of bleeding, defined as

  * prothrombin time test (INR value) \>1.4, platelet count \<70 (109/l), activated partial thromboplastin time (APTT) \>30s.
  * known bleeding disorders such as haemophilia, von Willebrand disease or platelet disorders.
  * any anticoagulants or antiplatelet treatment that cannot be temporarily paused

Where it's running

• Karolinska University hospital
  Solna, Sweden Recruiting

Study contacts

• Study coordinator: Thuy Tran, Associate Prof, PharmD, PhD
• Email: thuy.tran@regionstockholm.se
• Phone: +46812377777

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

• Delayed PSMA PET/CT to improve detection of significant prostate cancer before biopsy

  This study tests whether adding a delayed (2–3 hour) PSMA PET/CT scan improves detection of clinically significant prostate cancer in treatment‑naïve men who are awaiting biopsy compared with the standard 60‑minute scan.

  Recruiting at 9 sites Xijing Hospital · Lanzhou, Gansu and 8 other locations · NCT07531329

• ctDNA-guided sequential anti-HER2 therapy with CNS prophylaxis for HER2-positive metastatic breast cancer

  This trial will test whether using regular ctDNA blood tests to guide stepping up or down sequential anti-HER2 treatments, together with local therapies and measures to protect the brain and spinal cord, can produce long-lasting remission for people with HER2-positive stage IV breast cancer.

  Recruiting at 7 sites Phase 2 Memorial Sloan Kettering Cancer Center · Basking Ridge, New Jersey and 6 other locations · NCT07459673

• Disitamab vedotin plus bevacizumab for HER2-low metastatic breast cancer after T‑DxD failure

  This study will try disitamab vedotin combined with bevacizumab in adults with HER2‑low metastatic breast cancer whose disease progressed after trastuzumab deruxtecan.

  Recruiting Phase 2 The First Affiliated Hospital with Nanjing Medical University · Nanjing, Jiangsu · NCT07446452

• Mutant-selective inhibitor CGT6297 in advanced solid tumors with PIK3CA mutations

  This phase 1 study tests CGT6297 to see if it is safe and tolerable, and to get an early sense of activity, in adults with advanced solid tumors that have PIK3CA mutations.

  Recruiting at 12 sites Phase 1 Cogent Biosciences, Inc. · Scottsdale, Arizona and 11 other locations · NCT07383506

• Trastuzumab deruxtecan plus pertuzumab with proactive side-effect monitoring for first-line HER2-positive metastatic breast cancer

  This trial will try trastuzumab deruxtecan together with pertuzumab and digital tools to catch and manage side effects early in people starting first-line treatment for HER2-positive metastatic breast cancer.

  Recruiting at 12 sites Phase 2 SOLTI Breast Cancer Research Group · Villejuif and 26 other locations · NCT07371585

• Trastuzumab-rezetecan for HER2-positive and HER2-low breast cancer

  This project will test Trastuzumab-rezetecan in adults with HER2-positive or HER2-low breast cancer who are receiving it as part of routine care to see if it works and is safe.

  Recruiting Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University · Guangzhou, Guangdong · NCT07358182

How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.