Back to search results

STEMVAC Vaccine with Standard Therapies for Metastatic Breast Cancer

This study is testing a vaccine called STEMVAC along with standard treatments for metastatic hormone receptor-positive, HER2-negative breast cancer. Metastatic means the cancer has spread to other parts of the body. STEMVAC is designed to help your immune system fight cancer cells. The study will look at how safe STEMVAC is and if your body makes an immune response to it. You could be eligible if you are at least 18 years old and have this specific type of breast cancer. The study aims to enroll 40 participants.

Study design
This is an interventional study with an unclear phase, enrolling 40 participants into two groups based on their response to endocrine therapy.
What's involved
You would receive the STEMVAC vaccine through injections, along with either standard endocrine therapy and a CDK4/6 inhibitor, or capecitabine chemotherapy. You would also have blood tests, CT or PET scans, and image-guided biopsies for research.
Compensation
Not stated in the trial record.
Follow-up
After completing study treatment, participants will be followed every 6 months for 3 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.

NCT07112053

A Vaccine (STEMVAC) With Standard Endocrine-Based Therapy or Chemotherapy for the Treatment of Metastatic Hormone Receptor Positive, HER2 Negative Breast Cancer

Recruiting
PHASE2Ages 18+InterventionalTreatment
University of Washington
~40 participants
Updated 2026-04-06 on ClinicalTrials.gov
What's tested:CD105/Yb-1/SOX2/CDH3/MDM2-polyepitope Plasmid DNA VaccineCapecitabineComputed TomographyCyclin-Dependent Kinase 4 InhibitorCyclin-Dependent Kinase 6 InhibitorF-18 16 Alpha-Fluoroestradiol

At a glance

Recruiting sites
1 of 1 listed site is recruiting right now
RecruitingSuspended, closed, or not yet open
What they're measuring
Incidence of adverse events (AEs)
Measured over Up to 3 years after completion of study treatment
+1 more outcome measured

Conditions

Anatomic Stage IV Breast Cancer AJCC v8
Metastatic HER2-Negative Breast Carcinoma
Metastatic Hormone Receptor-Positive Breast Carcinoma

Explore related trials

Breast Carcinoma

Where it's being run

1 sites across 1 states
Washington1

Study leadership

  • Natasha Hunter, MD · PRINCIPAL_INVESTIGATOR · Fred Hutch/University of Washington Cancer Consortium

Who to contact

Research Coordinator(s)
[email protected]
1-866-932-8588
Email the study team

Opens a ready-to-send draft in your own email app — review before sending.

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.

Check eligibility for this trial ~2 min · HIPAA-protected · delete anytime
Eligibility criteria

Inclusion

Patients must be at least ≥ 18 years of age
Histologically confirmed hormone receptor positive metastatic breast cancer: Tumors that are positive for estrogen receptor (ER) and/or progesterone receptor (PR)
HER2-negative or HER2-low will be included and defined as:
0-1+ HER2 expression by immunohistochemistry (IHC) OR
Fluorescence in situ hybridization (FISH) negative OR
HER2 2+ and FISH negative
HER2 low per standard of care in breast cancer
Patients should be receiving the following therapies to be eligible for the study:
Cohort 1: First or second line of endocrine therapy in the metastatic setting, in combination with a CDK4/6 inhibitor. Patients must have completed at least 2 cycles of CDK4/6 inhibitor. Patients who have stopped endocrine therapy for intolerance but remain on abemaciclib monotherapy will be considered for enrollment at the PI's discretion
Cohort 2: Progressed on endocrine-based therapies and after completion of at least 1 cycle of capecitabine
Subjects with Eastern Cooperative Oncology Group (ECOG) Performance Status Score of 0 or 1
Willing to undergo up to two serial biopsies while on study
Have at least 1 site of disease confirmed by the treating oncologist that could be biopsied during treatment
White blood cell (WBC) ≥ 2000/mm\^3 (within 28 days of receiving the study vaccine)
Lymphocyte count ≥ 500/mm\^3 (within 28 days of receiving the study vaccine)
Absolute neutrophil count (ANC) ≥ 800/µL (within 28 days of receiving the study vaccine)
Platelets ≥ 75,000/µL (within 28 days of receiving the study vaccine)
Total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN), except patients with Gilbert's syndrome in whom total bilirubin must be ≤ 3.0 mg/dL (within 28 days of receiving the study vaccine)
Aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ≤ 3 x institutional upper limit of normal (ULN) (within 28 days of receiving the study vaccine)
Creatinine ≤ 2.0 mg/dL or creatinine clearance \> 30 mL/min (within 28 days of receiving the study vaccine)
Patients of child-bearing potential must agree to use dual methods of contraception and have a negative urine pregnancy test at screening, and male patients must use an effective barrier method of contraception if sexually active with a female of child-bearing potential. Acceptable methods of contraception are condoms with contraceptive foam, oral, implantable or injectable contraceptives, contraceptive patch, intrauterine device, diaphragm with spermicidal gel, or a sexual partner who is surgically sterilized or postmenopausal. Effective methods of contraception must be used throughout the study and until the end of treatment on study
Must have recovered from major infections and/or surgical procedures; and in the opinion of the investigator, not have any significant active concurrent medical illnesses or condition precluding protocol treatment

Exclusion

Patients with any of the following cardiac conditions:
Symptomatic restrictive cardiomyopathy
Dilated cardiomyopathy
Unstable angina within 4 months prior to enrollment
New York Heart Association functional class III-IV heart failure on active treatment
Symptomatic pericardial effusion
Uncontrolled hypertension
Uncontrolled cardiac arrhythmias
Patients with any autoimmune disease/comorbidity that require chronic steroids or immunosuppressants
A non-breast malignancy requiring radiation or systemic therapy within last 5 years
Known hypersensitivity reaction to the granulocyte-macrophage colony-stimulating factor (GM-CSF) adjuvant; any known contra-indication to GM-CSF
Pregnant or breast feeding
Known history of human immunodeficiency virus (HIV) infection, hepatitis B (e.g., hepatitis B virus surface antigen \[HBsAg\] reactive), or hepatitis C (e.g., hepatitis C virus \[HCV\] ribonucleic acid \[RNA\] \[qualitative\] is detected)
Major surgery within the 4 weeks prior to initiation of study vaccine
Current use of immunosuppressive agents or systemic corticosteroids. Topical, ocular, intra-articular, intranasal, and inhalational corticosteroids (with minimal systemic absorption) are allowed. Patients who have received systemic corticosteroids ≤ 30 days prior to starting study drug will be excluded
Patient is currently enrolled in any other clinical protocol or investigational trial that involves administration of experimental therapy and/or therapeutic devices, or investigational drug
NOTE: Biomarker or tissue collection or any other non-interventional clinical trial enrollment is allowed
Must be 14 days between a non-study vaccine and any STEMVAC vaccination
NOTE: The minimum of 14 days does not apply to the tetanus and diphtheria (Td) vaccine
Any condition that may interfere with the patient's participation in the study per treating oncologist

What this trial measures

  • Incidence of adverse events (AEs)Up to 3 years after completion of study treatment

    Safety and systemic toxicity will be determined by chemical and clinical parameters evaluated at various time points. Toxicity grading will be evaluated according to the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events version 6.0 and monitoring of AEs will be done per Food and Drug Administration and NCI guidelines. The type and grade of toxicities noted during the immunization regimen will be summarized. The duration of toxicities will also be summarized using descriptive statistics such as mean and standard deviation. All AEs noted by the investigator will be tabulated according to the affected body system. The frequency and severity of adverse events will be summarized with a proportion and a 95% confidence interval (CI).

  • Incidence of immunogenicityPre-vaccine up to after 2 booster doses of STEMVAC vaccine (Up to 40 weeks)

    Will be defined as the sum of the interferon gamma enzyme-linked immunosorbent spot of all STEMVAC antigens on blood samples collected pre-vaccine as compared to 1-month post dose #3 of the STEMVAC vaccine and again after 2 booster doses of STEMVAC vaccine. Both incidence and magnitude will be assessed. Immune responses will be summarized with mean and standard deviation or median and range (if skewness is observed) over time, the change over time will be summarized with graphs, and also analyzed using linear mixed-effects regression models with normalizing transformation if necessary.