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Recruiting Phase 1, Phase 2 NCT06966453

NCT06966453 A Study of Disitamab Vedotin in Adults With HER2 Expressing Advanced Breast Cancer

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Clinical Trial Summary
NCT ID NCT06966453
Status Recruiting
Phase Phase 1, Phase 2
Sponsor Pfizer
Condition Breast Cancer
Study Type INTERVENTIONAL
Enrollment 100 participants
Start Date 2025-06-30
Primary Completion 2027-10-25

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
Disitamab vedotin

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 1 is the earliest stage of human testing — safety and dosage are the primary focus. Visits are frequent and medical supervision is intensive. You will be among the first people to receive this treatment.

This trial targets 100 participants in total. It began in 2025-06-30 with a primary completion date of 2027-10-25.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

The purpose of this clinical study is to learn about the safety and effects of the study medicine (called disitamab vedotin) for the possible treatment of people with breast cancer that is hard to treat and has spread in the body (advanced cancer). This study is seeking participants who: * have breast cancer that is hard to treat and has spread in the body (advanced cancer) * have tumors that have HER2 on them * have received previous treatment for their advanced breast cancer All participants in this study will receive disitamab vedotin at the study clinic once every 2 weeks as an intravenous (IV) infusion (given directly into a vein). Participants will take the study medicine until they or their doctor decides to stop. This might be because their cancer is getting worse, the study medicine is no longer helping, they have bad side effects, or they wish to stop taking the study medicine. During this time, the participants will have study visits every 2 weeks. After the participants have stopped taking the study medicine, they will have follow-up visits about every 6 weeks unless their cancer gets worse. After that, they will have follow-up phone calls about every 12 weeks. The study team will look at the experiences of people receiving the study medicine. This will help the study team decide if the study medicine is safe and effective.

Eligibility Criteria

Inclusion Criteria: * 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. Prior therapy requirements for Cohort 1 (HER2+, HR+ or HR- participants): * 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. Prior therapy requirements for Cohort 2 (HR+/HER2-low participants): * 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. OR • Progressed on 1 line of ET for LA/mBC AND had a relapse while on adjuvant ET after definitive surgery for primary tumor AND had received a cyclin-dependent kinase (CDK) 4/6 inhibitor in the adjuvant or advanced setting if available as local standard of care and not contraindicated. Prior therapy requirements for Cohort 3 (HR+/HER2-ultralow or HR-/HER2-low \[HER2 low TNBC\] participants): * 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 Criteria: * 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.

Contact & Investigator

Central Contact

Pfizer CT.gov Call Center

✉ ClinicalTrials.gov_Inquiries@pfizer.com

📞 1-800-718-1021

Principal Investigator

Pfizer CT.gov Call Center

STUDY DIRECTOR

Pfizer

Frequently Asked Questions

Who can join the NCT06966453 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Breast Cancer. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT06966453 trial and what does that mean for participants?

Phase 1 trials are the first stage of human testing. The primary goal is to assess safety and determine appropriate dosage levels. Participants are closely monitored. These trials typically involve a small number of volunteers.

Is NCT06966453 currently recruiting?

Yes, NCT06966453 is actively recruiting participants. Contact the research team at ClinicalTrials.gov_Inquiries@pfizer.com for enrollment information.

Where is the NCT06966453 trial being conducted?

This trial is being conducted at Daphne, United States, Foley, United States, Mobile, United States, Gilbert, United States and 11 additional locations.

Who is sponsoring the NCT06966453 clinical trial?

NCT06966453 is sponsored by Pfizer. The principal investigator is Pfizer CT.gov Call Center at Pfizer. The trial plans to enroll 100 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: April 2026  ·  Data Methodology