Multi-peptide Vaccination and Bispecific PSMAxCD3 Antibody Treatment in Patients With Prostate Cancer

NCT07860047 | Recruiting Phase 2 DMC

• 3 other identifiers: ImmProCure2025-522144-41-002025
• Study Type: interventional
• Target: 84
• Locations: 1 country
• Sites: 4

Brief Summary

This trial is a phase II, randomized, open label study designed to evaluate safety, tolerability and efficacy of CC-1, a bispecific antibody (bsAb) with PSMAxCD3 specificity, and of VACXS15-PC01, a prostate cancer (PC)-specific multi-peptide vaccine, both administered as single agent or in combination to patients affected with biochemical recurrence (BCR) of PC after local therapy with curative intent. Patients will not receive other treatments during trial participation.

Conditions

Prostate Cancer

Keywords

biochemical recurrence of prostate cancer

Outcome Measures

Primary Outcomes (1)

• PSA response defined as ≥50% reduction in PSA at FU1 compared to baseline.

  PSA serum levels \[ng/ml\] are determined during screening, before every treatment, and then every 30 days until end of follow up. PSA serum levels for one study patient should be locally assessed in the same lab during the whole study treatment. Furthermore, 5ml serum are taken and should be processed locally and stored at -80 °C at the study site. Tübingen for central assessment of PSA.

  Screening: 21 days before Cycle (C1);C1: Day (D) -1, D0 to D3, D8, D15, and D22; C2-3: D1, D8, D15, and D22 (each cycle is 22 days); End of Treatment (EOT): D29 of C3; Follow-Up 1-5: every 30 days after the EOT; End of study (EOS): 12 months after EOT

Study Arms (3)

Multi-peptide vaccine VAC-XS15-PC01

ACTIVE COMPARATOR

The vaccine VAC-XS15-PC01 consists of 300 µg of each of 10 PC-associated peptides. The vaccine cocktail (final volume 500 µL) will be administered subcutaneously (SC), adjuvanted with the TLR1/2 ligand XS15 (50 µg) and emulsified in Montanide ISA 51 VG at a 1:1 ratio. A total of three vaccinations are planned in Arm 1, administered 4 weeks apart from each other.

Drug: Multipeptide Vaccine VAC-XS15-PC01

PSMAxCD3 bispecific antibody CC-1

ACTIVE COMPARATOR

CC-1 is applied subcutaneously once per week for 12 weeks in Arm 2. Due to priming doses up to 14 applications are planned.

Drug: PSMAxCD3, bispecific antibody CC-1

PSMAxCD3 bispecific antibody CC-1 + Multi-peptide vaccine VAC-XS15-PC01

EXPERIMENTAL

The vaccine VAC-XS15-PC01 consists of 300 µg of each of 10 PC-associated peptides. The vaccine cocktail (final volume 500 µL) will be administered subcutaneously (SC), adjuvanted with the TLR1/2 ligand XS15 (50 µg) and emulsified in Montanide ISA 51 VG at a 1:1 ratio. A total of three vaccinations are planned in Arm 3, administered 4 weeks apart from each other. CC-1 is applied subcutaneously once per week for 12 weeks in Arm 3. Due to priming doses up to 14 applications are planned.

Drug: PSMAxCD3, bispecific antibody CC-1; Drug: Multipeptide Vaccine VAC-XS15-PC01

Interventions

PSMAxCD3, bispecific antibody CC-1 DRUG

CC-1 is applied subcutaneously once per week for 12 weeks in Arm 2. Due to priming doses up to 14 applications are planned.

PSMAxCD3 bispecific antibody CC-1; PSMAxCD3 bispecific antibody CC-1 + Multi-peptide vaccine VAC-XS15-PC01

Multipeptide Vaccine VAC-XS15-PC01 DRUG

The vaccine VAC-XS15-PC01 consists of 300 µg of each of 10 PC-associated peptides. The vaccine cocktail (final volume 500 µL) will be administered subcutaneously (SC), adjuvanted with the TLR1/2 ligand XS15 (50 µg) and emulsified in Montanide ISA 51 VG at a 1:1 ratio. A total of three vaccinations are planned in Arm 1, administered 4 weeks apart from each other.

Multi-peptide vaccine VAC-XS15-PC01; PSMAxCD3 bispecific antibody CC-1 + Multi-peptide vaccine VAC-XS15-PC01

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Understand and voluntarily sign an IC document prior to any study related assessments/procedures
• Understand and voluntarily sign an IC document prior to any study related assessments/procedures
• Patient is able to understand and comply with the protocol for the duration of the study including treatment and scheduled visits and examinations
• Men aged ≥ 18 and ≤80 years
• Histologic diagnosis of prostatic adenocarcinoma
• Biochemical recurrence (BCR): PSA recurrence after treatment with curative intent; PSA ≥0.2 ng/mL or PSA \> nadir + 2 ng/mL (after definitive RT), with two increasing PSA values prior to study treatment; AND no distant metastasis upon PSMA-PET imaging
• Patients are ineligible to receive available treatment alternatives
• Low risk of rapid disease progression, defined as:
• o PSA-DT \> 1 year AND pathological ISUP grade \< 4 for men with prior RP OR Interval to BCR \> 18 months AND biopsy ISUP grade \< 4 for men with prior radiation therapy
• In case of second relapse PSA-DT \> 9 months
• Eastern Cooperative Oncology Group (ECOG) performance status ≤1

You may not qualify if:

• PSA \>5 ng/mL (at screening)
• Patients who are receiving or have previously received androgen deprivation treatment.
• Except testosterone has recovered to normal levels: patients who have previously received anti-hormonal treatment testosterone must be \>12 nmol/l.
• Patients who are planned to or are undergoing salvage therapy (e.g. radiation)
• Clinically significant xerostomia (dry mouth \>1grade according to CTCAE v6.0)
• Untreated current or prior distant metastasis of PC
• Other malignancy within the last 2 years except: adequately treated non-melanoma skin cancer and non-muscle invasive bladder cancer.
• Concurrent or previous treatment within 30 days in another interventional clinical trial with an investigational anti-cancer therapy
• Clinical signs of active infection (\> grade 2 according to CTCAE v6.0)
• History of HIV infection
• Viral active or chronic hepatitis (HBV or HCV)
• Autoimmune disease that requires or has required treatment with systemic immunosuppressive treatments, except low dose corticosteroids (\< 10 mg/ day), in the past 1 year
• Ongoing relevant CNS pathology (e.g. seizure, paresis, aphasia, cerebrovascular ischemia, severe brain injuries, dementia, Parkinson's disease, cerebellar disease, organic brain syndrome, psychosis, coordination or movement disorder)
• Epilepsy requiring pharmacologic treatment
• Major surgery within 4 weeks of starting study treatment. Patients must have recovered from any effects of major surgery.

Sponsors & Collaborators

• University Hospital Tuebingen: lead

Study Sites (4)

NCT Studienzentrale; Nationales Centrum für Tumorerkrankungen (NCT) Heidelberg

Heidelberg, Baden-Wurttemberg, 69120, Germany

NOT YET RECRUITING

CCU Transltional Immunolgy, University Hospital Tübingen

Tübingen, Baden-Wurttemberg, 72076, Germany

RECRUITING

Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin - Studienzentrale Onkologie

Berlin, Beriln, 12203, Germany

NOT YET RECRUITING

Universitätsklinikum Essen, Abteilung Urologie

Essen, North Rhine-Westphalia, 45147, Germany

NOT YET RECRUITING

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

Central Study Contacts

Susanne Jung, Dr. med.

CONTACT

+49 (0)7071-29 83275; kketi@med.uni-tuebingen.de

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: The study entails three-arms: (1) the multi-peptide vaccine VAC-XS15-PC01 alone, (2) PSMAxCD3 bispecific antibody CC-1 alone and (3) combinatorial treatment of CC-1 and VAC-XS15-PC01. Up to 84 patients are recruited (n = up to 28 per arm) and patients are randomly assigned 1:1:1 (drop-out rate of 15% anticipated). A translational research program comprising, among others, a strict evaluation of prostate specific antigen (PSA) course integrated with analysis of CC-1 induced immune response and immunogenicity of VAC-XS15-PC01 serves to detect early signs of efficacy. Furthermore, safety of the investigational medical products is evaluated, and tolerability of their combination are assessed.

Study Record Dates

• First Submitted: September 24, 2026
• First Posted: October 6, 2026
• Study Start: September 24, 2026
• Primary Completion (Estimated): March 31, 2029
• Study Completion (Estimated): March 31, 2030
• Last Updated: October 6, 2026

Record last verified: 2026-10

Locations

DE (4)