MR001 treatment for locally recurrent or metastatic triple-negative breast cancer.

A Phase Ib/IIa, Open-Label, Two-Cohort, Dose-Escalation and Dose-Expansion Clinical Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and Preliminary Anti-tumor Activity of MR001 in Patients With Locally Recurrent or Metastatic Advanced Triple-Negative Breast Cancer (TNBC) Who Have Progressed After First-Line or Later-Line Therapy

This will test MR001, a bispecific antibody, to see if it is safe and helps people with locally recurrent or metastatic TNBC who have progressed after prior therapy.

Quick facts

• Phase: PHASE1; PHASE2
• Study type: Interventional
• Enrollment: 42 (estimated)
• Ages: 18 Years to 75 Years
• Sex: All
• Sponsor: Shenzhen Majory Biotechnology Co., Ltd. (industry)
• Locations: 1 site (Beijing)
• Trial ID: NCT07208149 on ClinicalTrials.gov

What this trial studies

This Phase Ib/IIa, open-label, dual-cohort study includes a dose-escalation phase followed by dose-expansion to test MR001 in patients with locally recurrent or metastatic TNBC who have progressed after first-line or later therapy. The trial will collect safety, tolerability, pharmacokinetics, and preliminary anti-tumor activity data using RECIST v1.1 measurable disease criteria. Eligible patients must have histologically confirmed TNBC, an ECOG performance status of 0–1, adequate organ function, and a life expectancy over three months. The study is conducted at Cancer Hospital Chinese Academy of Medical Sciences in Beijing and uses regular clinic visits and imaging to monitor response and adverse events.

Who should consider this trial

Good fit: Ideal candidates are adults with histologically confirmed locally recurrent or metastatic TNBC, measurable disease, ECOG 0–1, adequate organ function, life expectancy >3 months, and progression after first-line or later therapy who can travel to the study site.

Not a fit: Patients who require systemic immunosuppression, have recent major surgery, severe hypersensitivity to similar biologics, poor organ function, uncontrolled comorbidities, or ECOG >1 are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, MR001 could offer a new treatment option that shrinks tumors or prolongs disease control for patients with advanced TNBC who have exhausted approved therapies.

How similar studies have performed: Bispecific antibodies and other immunotherapies have shown promising early-phase activity in some TNBC patients, but large trials confirming durable benefit in this setting remain limited.

Eligibility criteria

Inclusion Criteria:

* Patients with histologically or cytologically confirmed triple-negative breast cancer (TNBC).
* Subjects with locally recurrent or metastatic advanced TNBC who have progressed after first-line or later-line therapy.
* Presence of at least one measurable lesion according to RECIST V1.1 criteria.
* ECOG Performance Status 0 or 1.
* Life expectancy \>3 months.
* Adequate organ and hematopoietic function based on the laboratory tests.
* Voluntarily sign the informed consent form.

Exclusion Criteria:

* History of severe allergy or hypersensitivity to the investigational product or its excipients or drugs of similar chemical class (e.g., monoclonal antibodies), or contraindications to the investigational product.
* Requirement for systemic immunosuppressive therapy within 14 days prior to the first dose of study drug or during the study.
* Major surgery (excluding puncture biopsy) within 4 weeks prior to the first dose of study drug, or anticipated need for major surgery during this study.
* Uncontrolled active brain metastases or leptomeningeal metastasis.
* History of autoimmune disease requiring treatment with corticosteroids or immunosuppressive drugs.
* Women in the period of preconception, pregnancy, or lactation.
* Any other circumstances which the investigator considers may increase risks to subjects or interfere with the results of the trial.

Where this trial is running

Beijing

• Cancer Hospital Chinese Academy of Medical Sciences — Beijing, China (RECRUITING)

Study contacts

• Principal investigator: Binghe Xu — Cancer Institute and Hospital, Chinese Academy of Medical Sciences
• Study coordinator: Qingshan Xue

Conditions: Triple-Negative Breast Cancer