A Phase 1 interventional study of DPX-Survivac and Letrozole 2.5mg in Breast Cancer, sponsored by Providence Health & Services. Active, not recruiting at 1 site in United States. Open to female participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-04-13.
Sponsored by Providence Health & Services · Phase 1, Interventional, and Treatment
The study seeks to establish the safety of neoadjuvant aromatase inhibitor with: DPX-Survivac, DPX-Survivac plus radiation, or DPX-Survivac with cyclophosphamide in stage I to III HR+HER2- breast cancer. There will be sequential enrollment into 3 arms with an anticipated N=6 participants per arm for N=18 participants in total. All participants will receive letrozole 2.5 mg daily during the 6 weeks of neoadjuvant therapy. Neoadjuvant therapy occurs weeks 1-6, with standard of care surgery taking place week 7 to 9.
Women with hormone receptor positive, HER2-negative (HR+/HER2-) breast cancer with large tumors or positive lymph nodes have low response rates with neoadjuvant chemotherapy. Survivin is overexpressed in HR+HER2- breast cancer. Increasing tumor-specific Th1 immunity by administration of DPX-Survivac may alter the immune environment of these tumors. Radiation is a standard component of breast cancer therapy causing a reduction in local recurrences and improved breast cancer specific survival. Low dose cyclophosphamide can deplete regulatory T-cells without altering levels of effector T-cells. The investigators predict that combining a vaccine targeting Survivin, overexpressed in HR+HER2- tumors, with other immune modulating therapies such as radiation or low dose cyclophosphamide can enhance the efficacy of DPX-Survivac.
Primary Objective
1) Safety of neoadjuvant aromatase inhibitor with: DPX-Survivac, DPX-Survivac plus radiation, or DPX-Survivac with cyclophosphamide in stage I to III HR+HER2- breast cancer Secondary Objectives
Exploratory Objectives
12,544 studies on the registry are indexed under Breast Neoplasms; 2,892 are open to participants now.
This study's enrollment of 6 is below the median of 72 across 9,303 interventional studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Providence Health & Services is the lead sponsor of 83 studies on the registry; 6 are open to participants now.
Of its 10 completed or terminated interventional studies of FDA-regulated products, 8 (80%) have results posted.
Counted across the registry records on this site, refreshed daily.
HER2 negative is defined as:
0-1+ HER2 expression by immunohistochemistry (IHC) OR Fluorescence in situ hybridization (FISH) negative OR HER2 2+ and FISH negative
Adequate laboratory values within 30 days of enrollment defined as follows:
Exclusion Criteria:
8) Prior radiation to the affected breast 9) Previous cancers except for non-melanoma skin cancers or high risk cervical lesions in the past 5 years.
10) Previous breast cancer, tamoxifen, or aromatase inhibitor use. 11) Previous investigational immune therapy use-
Letrozole 2.5 mg po daily, DPX-Survivac 0.25 mL SC week 2 and Week 5
Biological: DPX-Survivac · Drug: Letrozole 2.5mg
Letrozole 2.5 mg po daily, XRT 10 Gy x 2, DPX-Survivac 0.25 mL SC week 2 and Week 5
Biological: DPX-Survivac · Drug: Letrozole 2.5mg · Radiation: XRT 10Gy x2
Letrozole 2.5 mg po daily, cyclophosphamide 50 mg po BID, DPX-Survivac 0.25 mL SC week 2 and Week 5
Biological: DPX-Survivac · Drug: Letrozole 2.5mg · Drug: Cyclophosphamide 50mg
DPX is a novel formulation that when combined with target antigens acts to activate T cells. It is a lipid-based formulation that creates a long lasting depot at the site of injection, forcing an "active uptake" by antigen presenting cells (APCs). APCs traffic to regional lymph nodes where naïve T cells are activated, inducing strong and sustained immune responses. All arms will receive DPX-Survivac on weeks 2 and 5.
Aromatase inhibitor all arms will receive
Also known as: Femara
oral chemotherapy used in the neoadjuvant setting for Arm C only
Also known as: cytoxan
Directed radiation at week 4 for Arm B only
Number of participants without the following safety events: TASAEs, persistent grade III/IV TAAEs, or toxicity-related delays in curative-intent surgery. Toxicity graded by CTCAE v5.0 and monitoring of AEs performed per FDA and NCI guidelines.
yes/no outcome variable, ascertained for each individual subject, and reported as a binomial proportion for each arm. Safety will be reported for all subjects who receive at least one dose of drug/radiation/study therapy
Time frame: The safety assessment period begins with day 1 and ends within 30 days of surgical excision.
Immunogenicity of each therapeutic arm IFN-γ ELISPOT
assessed by IFN-γ ELISPOT in PBMC
Time frame: throughout the study day 1, Day 8, Day 15, Day 29, Day 36, Week 7-9, Week 11, and 6 months post-surgery
Immunogenicity of each therapeutic arm GEO-Mx digital spatial profiler
assessed by GEO-Mx digital spatial profiler evaluation of Formalin-Fixed, parafin-embedded (FFPE) tumor and TCRβ evaluation for surviving-specific T cells in the tumor
Time frame: throughout the study day 1, Day 8, Day 15, Day 29, Day 36, Week 7-9, Week 11, and 6 months post-surgery
Plan to share: No
This study is active, not recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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Providence Health & Services