NCT07574541

Brief Summary

Background: Prostate cancer is the second most common cause of cancer-related death among men in the United States. Early-stage, low-grade prostate cancer is managed with active monitoring. However, 35% of men with this cancer will need treatment within 5 years because of tumor growth. Researchers want to know if a new vaccine that targets 3 anti-cancer proteins (TriAdeno) plus a drug (N-803) approved for bladder cancer can help stop prostate tumors from growing. Objective: To test TriAdeno and N-803 in people with early-stage prostate cancer. Eligibility: People aged 18 years and older with early-stage low- or medium-risk prostate cancer. Design: Participants will be screened. They will have a physical exam with blood tests. They will have a test of their heart function. They will have an imaging scan. They may have a rectal exam. TriAdeno is injected under the skin of the upper thigh; N-803 is injected under the skin of the abdomen. Participants will be treated in up to four 21-day cycles. They will get both injections on the first day of each cycle. Participants may opt to complete a memory aid: They may record all of their symptoms for 7 days after each injection. They may also complete a questionnaire about their prostate symptoms. Blood tests, imaging scans, and other tests will be repeated during the study. A tissue sample (biopsy) of the tumor will be collected during or after cycle 2; a second biopsy may be taken about 1 year later. Participants will have follow-up phone calls for 5 years....

Trial Health

63
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
52

participants targeted

Target at P25-P50 for phase_2

Timeline
25mo left

Started May 2026

Geographic Reach
1 country

1 active site

Status
not yet recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

May 7, 2026

Completed
1 day until next milestone

First Posted

Study publicly available on registry

May 8, 2026

Completed
5 days until next milestone

Study Start

First participant enrolled

May 13, 2026

Expected
1.1 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

June 15, 2027

1 year until next milestone

Study Completion

Last participant's last visit for all outcomes

June 15, 2028

Last Updated

May 8, 2026

Status Verified

May 5, 2026

Enrollment Period

1.1 years

First QC Date

May 7, 2026

Last Update Submit

May 7, 2026

Conditions

Keywords

Immune Infiltration

Outcome Measures

Primary Outcomes (1)

  • To determine the effect of TriAdeno vaccine with N-803 on immune infiltration of the local tumor environment

    Change in the density of T-cell immune infiltrates in the malignant portions of prostate using a paired two sample t-test

    Baseline/prior to treatment, C2D14 (or as late as C4D21), and optionally at 1 year

Secondary Outcomes (2)

  • To assess the adverse events associated with TriAdeno vaccine and N-803

    Day 1 of each cycle, and through at least 30 days after last treatment

  • To determine the effect of the TriAdeno vaccines with N-803 on the change in PSA

    Day 1 of each cycle after C1, 30 days after last treatment, and in follow-up about every 3 months for 1 year and every 6 months for the subsequent 4 years after the end of study therapy

Study Arms (1)

Arm 1

EXPERIMENTAL

TriAdeno vaccine with N-803

Biological: TriAdeno vaccineDrug: N-803

Interventions

The TriAdeno vaccine will be administered on Day 1 of every 21-day cycle for up to 4 cycles.

Arm 1
N-803DRUG

N-803 will be administered on Day 1 of every 21-day cycle for up to 4 cycles.

Arm 1

Eligibility Criteria

Age18 Years - 120 Years
Sexmale
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Histologically confirmed diagnosis of organ confined, low- or intermediate-risk PCa (Gleason grade group 1 or 2) identified in at least one prostate biopsy core. Biopsies performed at outside institutions should have Gleason score confirmed at the NCI by a genitourinary (GU) pathologist.
  • Participants must be on active surveillance.
  • Pre-study treatment tissue availability (at least one formalin-fixed paraffin embedded \[FFPE\] biopsy core or one H and E-stained slide and at least 5 unstained slides) obtained between 3 and 24 months prior to treatment initiation is mandatory for study initiation.
  • Serum PSA level of \<20 ng/mL (or \<10ng/mL for participants being treated with 5- alpha-reductase inhibitors)
  • Clinical stage \<=T2a by digital rectal exam (DRE)
  • Age \>=18 years
  • Eastern Cooperative Oncology Group (ECOG) performance status \<=1.
  • Adequate organ and marrow function as defined below:
  • Absolute neutrophil count (ANC) \>=1.0 x 109/L
  • Hemoglobin (Hgb) \>=9 g/dL
  • Platelets \>=75,000/mcL
  • Prothrombin International Normalized Ratio (INR) \<1.5 x upper limit of normal (ULN)
  • Partial thromboplastin time (PTT) \<1.5 x ULN
  • Total bilirubin \<1.5 x ULN
  • Aspartate aminotransferase (AST) \<=2.5 x ULN
  • +7 more criteria

You may not qualify if:

  • Prior treatment for PCa by surgery, radiation, local ablative (i.e., cryosurgery or highintensity focused ultrasound), or androgen-deprivation therapy.
  • Evidence of PCa with metastatic disease.
  • Prior treatment with adenovirus-based vector immunotherapy, adenovirus-based vaccines, or investigational vaccines.
  • Prior solid organ or bone marrow transplant.
  • Immunodeficiency or splenectomy.
  • Presence of a known active acute or chronic infection, including human immunodeficiency virus (HIV), confirmed by PCR, and hepatitis B virus (HBV) and hepatitis C virus (HCV), as determined by hepatitis B surface antigen (HBsAg) and HCV serology.
  • History of autoimmune disease (active or past), except for autoimmune-related thyroid disease, type I diabetes, and vitiligo if the condition(s) is well controlled.
  • History of heart disease, such as congestive heart failure (class II, III, or IV defined by the New York Heart Association functional classification), history of unstable or poorly
  • controlled angina, or history (\<1 year prior to initiation of study therapy) of ventricular arrhythmia.
  • Acute or chronic skin disorders that will interfere with injection into the skin of the extremities or subsequent assessment of potential skin reactions.
  • Second malignancy within 3 years prior to initiation of study therapy. Note: Individuals with curatively treated non-melanoma skin cancers or non-muscle invasive bladder cancer will not be excluded.
  • History of herbal products that may decrease PSA levels (e.g., saw palmetto).
  • Participants who have undergone surgery within 4 weeks prior to initiation of study therapy.
  • Participants receiving any other investigational agents within 30 days prior to initiation of study therapy.
  • History of allergic reaction attributed to compounds of similar chemical or biological composition to the study drugs.
  • +1 more criteria

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

National Institutes of Health Clinical Center

Bethesda, Maryland, 20892, United States

Location

Related Links

MeSH Terms

Conditions

AdenocarcinomaProstatic NeoplasmsNeoplasmsCarcinomaNeoplasms, Glandular and EpithelialNeoplasms by Histologic Type

Interventions

ALT-803

Condition Hierarchy (Ancestors)

Genital Neoplasms, MaleUrogenital NeoplasmsNeoplasms by SiteGenital Diseases, MaleGenital DiseasesUrogenital DiseasesProstatic DiseasesMale Urogenital Diseases

Study Officials

  • Peter A Pinto, M.D.

    National Cancer Institute (NCI)

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Peter A Pinto, M.D.

CONTACT

Study Design

Study Type
interventional
Phase
phase 2
Allocation
NA
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
NIH
Responsible Party
SPONSOR

Study Record Dates

First Submitted

May 7, 2026

First Posted

May 8, 2026

Study Start (Estimated)

May 13, 2026

Primary Completion (Estimated)

June 15, 2027

Study Completion (Estimated)

June 15, 2028

Last Updated

May 8, 2026

Record last verified: 2026-05-05

Data Sharing

IPD Sharing
Will share

This study will comply with the NIH Data Management and Sharing (DMS) Policy, which applies to all new and ongoing NIH-funded research in the IRP, as of January 25, 2023, that is associated with a ZIA, with a clinical protocol that undergoes scientific review and/or will involve genomic data sharing.

Shared Documents
STUDY PROTOCOL, SAP, ICF
Time Frame
Data will be made available as soon as possible or at the time of associated publication. Data not published in a manuscript will be shared via public source once the data set completes QC.
Access Criteria
Clinical data will be made available upon request and with the permission of the study Pl. Genomic data are made available via dbGAP through requests to the data custodians.

Locations