Prime-boost Immunotherapeutic Trial in Men With Biochemical Recurrence After Definitive Local Therapy for Prostate Cancer

NCT05617040 | Terminated Phase 1 Results DMC FDA Drug

• 1 other identifier: PCA001
• Study Type: interventional
• Target: 22
• Locations: 1 country
• Sites: 7

Brief Summary

This is a multi-centre, Phase 1/2, open-label clinical trial of the VTP-850 prime-boost immunotherapeutic in men with biochemical recurrence after definitive local therapy for prostate cancer.

Conditions

Prostate Cancer

Outcome Measures

Primary Outcomes (1)

• The Safety of VTP-850 Prime-boost Regimens, With the Booster Dose Administered Either IM or IV, and the Recommended Phase 2 Regimen (RP2R)

  Participants with AEs, ≥Grade 3 AEs, and serious adverse events.

  From the start of the first VTP-850 administration continuing until Month 6

Secondary Outcomes (1)

• The PSA Response Rate to VTP-850

  6 months

Study Arms (3)

IM/IM Low

EXPERIMENTAL

ChAdOx1-PCAQ 5\*10\^9 vp IM / MVA-PCAQ 5\*10\^7 pfu IM

Biological: ChAdOx1-PCAQ; Biological: MVA-PCAQ

IM/IM Full

EXPERIMENTAL

ChAdOx1-PCAQ 2.5\*10\^10 vp IM / MVA-PCAQ 2\*10\^8 pfu IM

Biological: ChAdOx1-PCAQ; Biological: MVA-PCAQ

IM/IV Full

EXPERIMENTAL

ChAdOx1-PCAQ 2.5\*10\^10 vp IM / MVA-PCAQ 2\*10\^7 pfu IV

Biological: ChAdOx1-PCAQ; Biological: MVA-PCAQ

Interventions

ChAdOx1-PCAQ BIOLOGICAL

Recombinant nonreplicating chimpanzee adenovirus Oxford 1 (ChAdOx1) vector encoding 4 prostate cancer antigens: prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), six-transmembrane epithelial antigen of prostate 1 (STEAP1), and an oncofoetal antigen (5T4).

IM/IM Full; IM/IM Low; IM/IV Full

MVA-PCAQ BIOLOGICAL

Replication-deficient recombinant Modified Vaccinia virus Ankara (MVA) vector encoding the same prostate cancer antigens as ChAdOx1-PCAQ (prostate-specific antigen (PSA), prostatic acid phosphatase (PAP), six-transmembrane epithelial antigen of prostate 1 (STEAP1), and an oncofoetal antigen (5T4))

IM/IM Full; IM/IM Low; IM/IV Full

Eligibility Criteria

• Age: 18 Years+
• Gender Eligibility Details: Male participants only
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Males aged 18 years and above at the time of signing the informed consent.
• Histologically or cytologically confirmed adenocarcinoma of the prostate.
• Has undergone primary therapy for prostate cancer (radical prostatectomy and/or definitive external beam radiation and/or brachytherapy). Salvage external radiation therapy (XRT) following radical prostatectomy \>6 months prior to Day 1 is allowed.
• No further local therapy to prostate or systemic therapy for prostate cancer and no metastasis-directed therapy for PSA positron emission tomography (PET) positive lesions planned within 4 months after the first dose of VTP-850.
• Serum testosterone \>175 ng/dL.
• Nonmetastatic (M0) disease and no evidence of prostatic bed recurrence verified by whole body bone scintigraphy and either CT or MRI. Note that a positive PSMA PET does not exclude the participant if the conventional scans are negative.
• Serum PSA of \>0.3 ng/mL for participants with prior radical prostatectomy (with or without salvage radiotherapy), or serum PSA of 2 ng/mL above nadir for participants with prior external beam radiation or brachytherapy.
• PSA doubling time ≤12 months.
• Not planning to start ADT for at least 4 months after Day 1.
• Eastern Cooperative Oncology Group (ECOG) Score 0 or 1.
• Baseline laboratory parameters must meet the following criteria:
• Haemoglobin ≥110 g/L
• White cell count ≥2.0×10\^9/L
• Absolute neutrophil count ≥1.5×10\^9/L
• Lymphocytes ≥0.9×10\^9/L

You may not qualify if:

• Any other prior malignancy within the past 5 years except for basal cell or squamous epithelial carcinomas of the skin that have been resected with no evidence of metastatic disease for 3 years.
• Unstable medical condition, drug or alcohol abuse, or medical or psychiatric condition that in the opinion of the investigator would affect the safety of the participant or the evaluation of the data or interfere with adherence to the trial requirements.
• Significant history of or current cardiovascular, respiratory, renal, gastrointestinal, endocrinological, haematological or neurological disorders constituting a risk when taking the trial intervention or interfering with the interpretation of data; cardiac event or heart failure in the previous 6 months.
• Active autoimmune disease that has required systemic treatment in past 2 years with use of disease modifying agents, chronic corticosteroids (\>14 days) or immunosuppressive drugs. Hormone replacement therapy (e.g., thyroxine, insulin or physiologic corticosteroid replacement therapy for adrenal or pituitary insufficiency) is allowed.
• History of severe allergy to eggs or history of severe reaction to any previous vaccination that required medical attention.
• Medical history that could increase the participant's risk of reaction to a vaccine, including but not limited to capillary leak syndrome, transverse myelitis, multiple sclerosis, Guillain Barré syndrome, significant thrombocytopenia, thrombosis with thrombocytopenia syndrome (also termed vaccine-induced thrombotic thrombocytopenia), heparin-induced thrombocytopenia, or hereditary angioedema, acquired angioedema or idiopathic angioedema.
• Any immunocompromised state, or history of solid organ or stem cell transplantation.
• Active infection requiring parenteral antibiotic therapy or causing fever (temperature ≥38.0˚C) within 7 days prior to Day 1, or unexplained fever (temperature ≥38.0˚C) within 7 days prior to Day 1.
• Known history of infection with hepatitis B virus, or human immunodeficiency virus, or active hepatitis C virus infection (antibody and RNA positive).
• Received XRT following radical prostatectomy within 6 months prior to Day 1.
• Received ADT outside of the initial primary therapy
• Prior chemotherapy or immunotherapy (including vaccines or checkpoint inhibitors) or experimental agent or participation in a clinical trial for prostate cancer with the exception of those taking part as primary treatment option.
• Received a vaccine with adenovirus vector within 3 months prior to Day 1.
• Received any live vaccine within 30 days prior to Day 1, or planned vaccination to occur within 3 months after Day 1.
• Received any non-live/inactivated vaccine within 14 days of Day 1 or planned non-live vaccination to occur within 10 weeks after Day 1.

Sponsors & Collaborators

• Barinthus Biotherapeutics: lead

Study Sites (7)

Washington University School of Medicine

St Louis, Missouri, 63110, United States

Location

Columbia University Irving Medical Center

New York, New York, 10032, United States

Location

Cornell University

New York, New York, 10065-4805, United States

Location

Fox Chase Cancer Center

Philadelphia, Pennsylvania, 19111, United States

Location

Carolina Urologic Research Center

Myrtle Beach, South Carolina, 29572, United States

Location

University of Virginia Health System

Charlottesville, Virginia, 22908, United States

Location

Fred Hutchinson Cancer Center

Seattle, Washington, 98109, United States

Location

MeSH Terms

Conditions

Prostatic Neoplasms

Condition Hierarchy (Ancestors)

Genital Neoplasms, Male; Urogenital Neoplasms; Neoplasms by Site; Neoplasms; Genital Diseases, Male; Genital Diseases; Urogenital Diseases; Prostatic Diseases; Male Urogenital Diseases

Limitations and Caveats

The trial was initially designed as a Phase 1/2 trial; however, the sponsor elected to discontinue the trial following completion of the Phase 1 portion.

Results Point of Contact

• Title: Chief Medical Officer
• Organization: Barinthus Biotherapeutics

enquiries@barinthusbio.com

+44 1865 818808

Publication Agreements

• PI is Sponsor Employee: No
• Restrictive Agreement: No

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Phase 1 will follow a 3+3 design and determine the RP2R (dose level of both ChAdOx1-PCAQ and MVA-PCAQ, and route of administration of MVA-PCAQ) that will be used in Phase 2. Phase 2 will consist of 2 sequential stages. Stage 1 will enroll 19 additional participants at the RP2R. If 4 or more participants treated at the RP2R have a PSA response, Stage 2 will be opened to enrolment of up to 100 additional participants.

Study Record Dates

• First Submitted: November 1, 2022
• First Posted: November 15, 2022
• Study Start: January 30, 2023
• Primary Completion: February 5, 2025
• Study Completion: February 5, 2025
• Last Updated: November 10, 2025
• Results First Posted: November 10, 2025

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

US (7)