Gallium (68Ga) tezatabep matraxetan for Breast cancer|Metastatic breast cancer

Inclusion criteria

• {"criterion_text":"-Female age ≥18 years"}
• {"criterion_text":"-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"}
• {"criterion_text":"-The patient must be able and willing to provide written consent to participate in the study"}
• {"criterion_text":"-At least one metastatic lesion ≥ 10 mm is available for biopsy. o\tException 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)."}
• {"criterion_text":"-At least one additional metastatic index lesion ≥ 10 mm for evaluation of treatment effect (according to RECIST v1.1)"}
• {"criterion_text":"-WHO performance status ≤ 2"}
• {"criterion_text":"-Expected survival > 12 weeks"}
• {"criterion_text":"-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 test before [68Ga]Ga-ABY-025 administration. Pregnancy testing prior to each administration of the IMP is obligatory."}

Exclusion criteria

• {"criterion_text":"-Contra-indications for treatment for trastuzumab deruxtecan and inability to undergo this treatment as per local treatment routines"}
• {"criterion_text":"-A previously documented metastatic tumor biopsy that was HER2-positive (IHC 3+ and/or HER2 gene amplification)"}
• {"criterion_text":"-Other manifest malignancies except for basal cell carcinoma of the skin"}
• {"criterion_text":"-Inadequate cardiac, renal, bone marrow or liver function"}
• {"criterion_text":"-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 or any anticoagulants or antiplatelet treatment that cannot be temporarily paused"}

Primary endpoints

• {"endpoint_text":"-The mean SUVmax in up to five ABY-025 avid lesions at the baseline investigation will be used to assess the primary objective of the study, i.e. to relate HER2-status on PET to the response according to RECIST v1.1 after 3-4 treatment cycles with T-DXd.","definition_or_measurement_approach":"Mean SUVmax measured in up to five ABY-025 avid lesions at baseline; correlated with response assessed by RECIST v1.1 after 3-4 cycles of trastuzumab deruxtecan (T-DXd)."}

Secondary endpoints

• {"endpoint_text":"-Changes (deltaSUVmax) in HER2-status in up to five target lesions according to [68Ga ]Ga-ABY-025 uptake prior to and after 3-4 cycles of treatment with T-DXd.","definition_or_measurement_approach":"Change in SUVmax (deltaSUVmax) measured in up to five target lesions on [68Ga]Ga-ABY-025 PET before and after 3-4 cycles of T-DXd."}
• {"endpoint_text":"-Correlation between HER2-expressing total tumor volume (HER2-TTV; defined as proportion of ABY-025 avid lesions in relation to the total tumor volume (TTV, lesions ≥10 mm) defined on CT) at baseline and ORR, Progression Free and Overall Survival after treatment with T-DXd","definition_or_measurement_approach":"HER2-TTV defined as proportion of ABY-025 avid lesions relative to total tumor volume (lesions ≥10 mm) on CT at baseline; correlated with objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) following T-DXd treatment."}
• {"endpoint_text":"-Change in patient reported Health-Related Quality of Life (HR-QoL) as measured by the EQ-5D-5L questionnaire from baseline to the first treatment evaluation","definition_or_measurement_approach":"Change from baseline in EQ-5D-5L scores to first treatment evaluation (patient-reported HR-QoL)."}

Sweden

Earliest CTIS Part Ii Submission Date

03-12-2024

Latest Decision Or Authorization Date

08-01-2026

Processing Time Days

401

Number Of Sites

3

Number Of Participants

70

Primary sponsor

Full Name

Karolinska University Hospital

Organisation Type

Hospital/Clinic/Other health care facility

Country Of Registered Address

Sweden

Third parties

• {"country":"Sweden","full_name":"Affibody AB","duties_or_roles":"Creator of the precursor ABY-025","organisation_type":"Pharmaceutical company"}