TRAIL-R2 and HER2 Bi-Specific Chimeric Antigen Receptor (CAR) T Cells for the Treatment of Metastatic Breast Cancer

Plain-language summary

This Phase 1 gene transfer study tests HTR2 T cells, T cells engineered with a bi-specific chimeric antigen receptor (CAR) targeting HER2 and TRAIL-R2, in patients with HER2-expressing metastatic breast cancer. The aim is to find the highest safe dose, see how long the cells persist in the body, learn about side effects, and see whether the cells can fight HER2-expressing breast cancer. Participants must be 18 to 80 years old with metastatic or locally recurrent unresectable breast cancer with HER2 expression of 1+, 2+ or 3+ by IHC that has progressed after at least one line of therapy.

The summary above is a plain-language rendering of the official record. The original English title is shown for reference.

Trial details

Phase

Phase 1

Status

Recruiting

Sponsor

Baylor College of Medicine

Intervention

HTR2 T Cells, HTR2 T Cells

Start date

8/3/2026

Estimated completion

1/1/2044

Countries

United States

Related genes

Locations

• Houston, United States

Eligibility criteria

Criteria are reproduced from the ClinicalTrials.gov record in the original English. Only the trial team can determine eligibility.

Procurement Inclusion Criteria:

1. Any patient between 18-80 years of age regardless of sex, with a diagnosis of metastatic or locally recurrent unresectable HER2 positive breast cancer.
2. HER2 tumor expression1+, 2+ or 3+ by IHC
3. The disease must have progressed after standard first line therapy. Patients are still eligible if they have failed more than one line of therapy.
4. Informed consent explained to, understood by and signed by patient/guardian. Patient/guardian given copy of informed consent.

Treatment Inclusion Criteria:

1. Patients between ages 18 and 80 years old with a diagnosis of either stage IV breast cancer or locally recurrent unresectable breast cancer. Disease must have progressed after standard first line therapy. Patients are still eligible if they have failed more than one line of therapy.
2. Measurable or evaluable disease per RECIST 1.1 criteria.
3. HER2 tumor expression 1+, 2+ or 3+ by IHC.
4. Bilirubin ≤ 3x upper limit of normal.
5. AST and ALT ≤ 3x upper limit of normal
6. Hemoglobin ≥ 7 g/dl (may be transfused values)
7. Serum creatinine \< 2 x the upper limit of normal.
8. Pulse oximetry of \> 90% on room air.
9. Off conventional or investigational therapy for 3 weeks prior to study entry.
10. ECOG Performance Status ≤ 2
11. The patient is able to understand and give informed consent to study related procedures and treatments.

Procurement Exclusion Criteria:

1. Known pregnancy or actively breast feeding.
2. Active and uncontrolled bacterial, viral, or fungal infection.
3. Patients with current use of systemic corticosteroids (Prednisone equivalent \>0.5mg/kg/day).
4. Patients with abnormal left ventricular function (LVEF \<55%)
5. Patients with brain metastases that are progressing.

Treatment Exclusion Criteria:

1. Pregnant or breast feeding
2. Active and uncontrolled bacterial, viral or fungal infection
3. Patient with current use of systemic corticosteroids (prednisone equivalent \>0.5 mg/kg/day.
4. Patients with abnormal left ventricular function (LVEF \<55%).
5. Patients with brain metastases that are progressing