A Study of Disitamab Vedotin for HER2-Expressing Advanced Breast Cancer
This study is looking into the safety and effects of a medicine called disitamab vedotin for adults with advanced breast cancer that has spread and is hard to treat. You might be able to join if your breast cancer has a specific marker called HER2 and you've already had treatment for your advanced cancer. The main goal is to see how many people respond to the treatment (objective response) over about two years. All participants will receive disitamab vedotin through an IV (into a vein) every two weeks until you or your doctor decide to stop.
- Study design
- This is an interventional study with a planned enrollment of 100 participants. It is studying the effects of disitamab vedotin.
- What's involved
- You will receive disitamab vedotin through an IV every two weeks at the study clinic. You will continue treatment until you or your doctor decides to stop.
- Compensation
- Not stated in the trial record.
- Follow-up
- Your response to treatment will be measured from the start of treatment until your disease gets worse or you pass away, for up to approximately two years.
AI-generated from the public study record. Only the study team can confirm whether you're eligible — confirm details with them before making decisions.
NCT06966453
A Study of Disitamab Vedotin in Adults With HER2 Expressing Advanced Breast Cancer
Recruiting
PHASE1Ages 18+InterventionalTreatmentPfizer
~100 participants
Updated 2026-04-21 on ClinicalTrials.gov
What's tested:Disitamab vedotin
At a glance
Recruiting sites
134 of 166 listed sites are recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Objective response (OR) by investigator assessment
Measured over From Cycle 1 Day 1 until disease progression by investigator assessment per RECIST version 1.1, or death due to any cause, whichever is earlier; up to approximately 2 years
Conditions
Where it's being run
166 sites across 39 statesTexas26
Florida25
Connecticut16
Virginia14
California13
Colorado13
Pennsylvania7
Georgia4
Study leadership
- Pfizer CT.gov Call Center · STUDY_DIRECTOR · Pfizer
Who to contact
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Do you actually qualify for this trial?
Add a private profile and we'll compare every criterion below against your situation — and tell you which ones are met, uncertain, or excluding.
Eligibility criteria
Inclusion
Histologically or cytologically confirmed diagnosis of locally-advanced, unresectable, or metastatic breast carcinoma.
Human epidermal growth factor receptor 2 (HER2) and hormone receptor (HR) status appropriate for enrollment in cohort.
HER2 status determined by most recent local assessment based on American Society of Clinical Oncology (ASCO) and College of American Pathologists (CAP) guidelines for assessment of HER2 in BC for interpretation of HER2 expression and amplification
HER2+: immunohistochemistry (IHC) 3+ or IHC 2+/in situ hybridization (ISH)+
HER2-low: IHC 1+/ISH-negative or untested or IHC 2+/ISH-negative
HER2-ultralow: IHC 0 with membrane staining (any staining of the membrane in \>0 and ≤10% of cancer cells) o HR+ disease is determined as either estrogen receptor (ER) and/or progesterone receptor (PgR) positive \[ER or PgR ≥1%\]) and HR negative disease is determined as both ER and PR negative \[ER and PgR \<1%\]) per ASCO/CAP guidelines in the advanced disease setting. If a patient has had multiple ER/PgR results for advanced disease, the most recent test result will be used to confirm eligibility.
Received prior trastuzumab, pertuzumab and a taxane if available as local first line standard of care therapy for advanced disease.
Prior tucatinib based therapy is allowed.
Must have progression on or after, or be intolerant to, T-DXd in any line advanced disease setting.
No more than 3 prior systemic cytotoxic therapy regimens (including antibody drug conjugates \[ADCs\]) for Locally Advanced (LA)/metastatic breast cancer (mBC). Participants previously treated with (neo)adjuvant cytotoxic therapy and have disease relapsed within 6 months of cytotoxic treatment is considered to have received 1 line of cytotoxic therapy for LA/mBC.
No more than 3 prior systemic cytotoxic therapy regimens (including ADCs) for LA/mBC. Participants previously treated with (neo)adjuvant cytotoxic therapy and have disease relapsed within 6 months of cytotoxic treatment is considered to have received 1 line of cytotoxic therapy for LA/mBC.
Participants with known germline breast cancer gene (BRCA) mutation must have received a poly-ADP ribose polymerase (PARP) inhibitor, where available and not medically contraindicated.
Must have progression on or after, or be intolerant to, trastuzumab deruxtecan (T-DXd) in any line advanced disease setting.
Must have intolerance to endocrine therapy (ET) or ET refractory disease:
Progressed on ≥2 lines of ET for LA/mBC AND had received a cyclin-dependent kinase (CDK)4/6 inhibitor in the adjuvant or metastatic setting if available as local standard of care and not contraindicated.
No more than 4 prior systemic cytotoxic chemotherapy regimens (including ADCs) for advanced or mBC. Participants previously treated with (neo)adjuvant cytotoxic therapy and have disease relapsed within 6 months of cytotoxic treatment is considered to have received 1 line of cytotoxic therapy for LA/mBC.
Known germline BRCA mutation must have received a PARP-inhibitor if available as local standard of care therapy and not medically contraindicated.
Prior sacituzumab govitecan is allowed.
Prior T-DXd is allowed.
Participants with HR negative (TNBC), HER2-low and programmed cell death receptor ligand 1 (PD-L1)-positive (combined positive score \[CPS\] ≥10) tumors must have received pembrolizumab (or other PD-L1 inhibitor) with chemotherapy if available as local standard of care therapy and not medically contraindicated.
Participants with HR+/HER2-ultra low tumors must have received at least 1 antihormonal therapy in any setting or be ineligible for ET.
Participants with HR+/HER2-ultra low tumors must have had prior therapy with a CDK4/6 inhibitor in the adjuvant or advanced setting.
Exclusion
Known hypersensitivity to any excipient contained in the drug formulation of disitamab vedotin.
Active central nervous system (CNS) and/or leptomeningeal metastasis.
Participants with a history of other invasive malignancy within 3 years before the Cycle 1 Day 1 (C1D1) of study intervention, or any evidence of residual disease from a previously diagnosed malignancy.
Prior therapy with ADCs with MMAE payload.
Participants who have received prior systemic anticancer treatment or radiotherapy within 2 weeks, or 5 half-lives, whichever is shorter, prior to C1D1 of study intervention. Note: If the last immediate anticancer treatment contained an antibody-based agent(s), then an interval of 28 days or 5 half-lives (whichever is shorter) of the agent(s) prior to receiving the study intervention treatment is required.
Participants must have recovered from all adverse events due to previous therapies.
What this trial measures
- Objective response (OR) by investigator assessmentFrom Cycle 1 Day 1 until disease progression by investigator assessment per RECIST version 1.1, or death due to any cause, whichever is earlier; up to approximately 2 years
The primary endpoint OR by investigator assessment is defined as the proportion of participants with confirmed CR or PR as determined by investigator per RECIST Version 1.1.