An Unblinded, Single Arm, Pilot Observational Study to Test the Safety, Tolerability, Immunogenicity and the Biological Effects of TRB-001 Vaccination.

An Unblinded, Single Arm, Pilot Observational Study to Test the Safety, Tolerability, Immunogenicity and the Biological Effects of TRB-001 Vaccination in Individuals Who Have Previously Undergone aSyn Immunotherapy

An unblinded, single arm, pilot observational study to test the safety, tolerability, immunogenicity and the biological effects of TRB-001 vaccination in individuals who have previously undergone aSyn immunotherapy

Study Overview

• Status: Recruiting
• Conditions: Parkinson's Disease
• Intervention / Treatment: Biological: TRB-001

• Study Type: Interventional
• Enrollment (Estimated): 6
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Markus Mandler; Phone Number: +43 699 11603817; Email: markus.mandler@tridem.at

Study Locations

• Austria
  • Vienna, Austria, 1180
    • Recruiting
    • PROSENEX Study Centre at the ATOMOS Klinik Währing
    • Contact: Dieter Volc, Dr.; Phone Number: +43 (0)1 261660; Email: dieter@volc.at

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• At least 18-years of age
• Female or male with previous treatment with active aSyn immunotherapy
• Parkinson's disease diagnosis (any stage)
• Understands and agrees to comply with the study procedures and provides written informed consent

Exclusion Criteria:

• Women of childbearing potential without use of contraception
• Women who are pregnant or lactating
• Contraindication for MRI or lumbar puncture
• Known or suspected allergy, or history of anaphylaxis, to vaccines or their excipients, if considered relevant by the investigator
• Presence or history of autoimmune disease or immunodeficiency, if considered relevant by the investigator
• Presence of active infectious disease (hepatitis B, hepatitis C, or human immunodeficiency virus (HIV))
• Significant cognitive impairment or clinical dementia, or a Montreal Cognitive Assessment (MoCA) score <26
• High suspicion of other parkinsonian syndromes, such as multiple system atrophy, progressive supranuclear palsy, drug-induced Parkinsonism and post-encephalitic Parkinsonism
• Any relevant systemic illness. This includes cardiovascular, hepatic, gastroenterological, respiratory, endocrinological, hematologic disease, or any other condition that, in the investigator's opinion, could interfere with the analyses of safety and efficacy in this study, unless patient has been on stable doses of medication for any of these concurrent illnesses for at least 3 months prior to study entry
• Unstable psychiatric illness, including psychosis, suicidal ideation, untreated major depression, schizophrenia, or bipolar affective disorder within 90 days before Visit 1, as determined by the investigator
• History of drug or alcohol abuse within the past 5 years
• Recent history (≤2 years) of cancer (exceptions; basal cell carcinoma, intraepithelial cervical neoplasia)
• Birthmarks, tattoos, wounds, or skin conditions that may obscure the assessment of injection site reactions
• Participation in the active treatment phase of any non-PD clinical trial within 30 days prior to Visit 1
• Dose limiting toxicity to previous immunization with aSyn-based PD vaccine
• Current immunosuppressive therapy
• Employee at the study site, spouse/partner or relative of any study staff (e.g. investigator, sub-investigators, or study nurse) or relationship to sponsor

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Verum Arm; Each participant will receive 1 immunization with Vaccine at week 0. Participants may also receive a 2nd immunization at week 4-6, pending safety and immunogenicity results and decision from PI, Sponsor, and Medical Monitor.

Biological: TRB-001; This is an unblinded, single arm, pilot observational study to test the safety, tolerability, immunogenicity and the biological effects of TRB-001 vaccination in individuals who have previously undergone aSyn immunotherapy. After the screening period, all participants who are enrolled in the study will receive a first intradermal TRB-001 immunization at a dose of 100μg. Patients antibody response will be assessed at week two (compared to baseline). Based on the safety and immunogenicity results, the PI, Medical Monitor, and Sponsor will decide on a potential second immunization with TRB-001. Regarding immunogenicity, a predefined cut-off will be used. The patient may be offered another injection to be applied 4-6 weeks after the first immunization with TRB-001. Participants will be evaluated at week 24. Assessments will include safety, immunogenicity, blood-/CS

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of local and systemic treatment-emergent adverse events (TEAEs)	Incidence of local and systemic treatment-emergent adverse events (TEAEs) (occurrence, intensity, duration, and relationship to IMP) over 6-months	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Titers of vaccine-induced antibodies in blood and CSF	Titers of vaccine-induced antibodies (immunizing peptide, aSyn monomer; area under the curve for both parameters) in blood and CSF (peptide only) over 6 months compared to baseline	6 months
Change from baseline in total aSyn levels	Change from baseline in total aSyn levels as assessed by ELISA in blood and CSF	6 months
Change in levels of aggregated aSyn in blood and CSF	Change from baseline in levels of aggregated aSyn in blood and CSF	6 months
Change in GFAP and Neurofilament light chain in CSF	Change from baseline in GFAP and Neurofilament light chain in CSF	6 months
Avidity of antibodies induced for aggregated aSyn	Avidity of antibodies induced for aggregated aSyn as assessed after the vaccination with TRB-001 compared to baseline	6 months
Selectivity of antibodies induced by TRB-001	Selectivity of antibodies induced by TRB-001 for aggregated aSyn	6 months
Change from baseline of the seed amplification assay signal (CSF)	Change from baseline of the seed amplification assay signal (CSF)	6 months
Correlation between measures of the antibody response	Correlation between measures of the antibody response (peptide titer, aSyn titer, avidity, titers x avidity, selectivity and biomarkers of the disease) (change from baseline in total aSyn levels, levels of aggregated aSyn in blood and CSF)	6 months
Change in MDS-UPDRS I, II, III, and IV	Change from baseline in MDS-UPDRS I, II, III, IV	6 months
Change from baseline in PD symptoms	Change from baseline in PD symptoms using the wearable device STAT-ON(TM)	6 months
Change in symptomatic PD medication	Change from baseline in symptomatic PD medication (Levodopa equivalent dose)	6 months
Change in levels of circulating extracellular vesicle (EV)-based biomarkers	Change from baseline in Levels of circulating extracellular vesicle (EV)-based biomarkers	6 months
Change in the number of vaccine specific B- and T cell clones	Change from baseline in the number of vaccine specific B- and T cell clones as assessed by B/T cell receptor sequencing	6 months
Incidence of local and systemic TEAEs	Incidence of local and systemic TEAEs over 12- months	12 months
Change from baseline in total aSyn levels	Change from baseline in total aSyn levels as assessed by ELISA in blood	12 months
Change from baseline in levels of aggregated aSyn in blood	Change from baseline in levels of aggregated aSyn in blood	12 months
Titers of vaccine-induced antibodies in blood	Titers of vaccine-induced antibodies (immunizing peptide, aSyn monomer; area under the curve for both parameters) in blood	12 months
Change from baseline in MDS-UPDRS I, II, III, IV at 12 month time period	Change from baseline in MDS-UPDRS I, II, III, IV	12 months
Change from baseline in PD symptoms at 12 month time period	Change from baseline in PD symptoms using the wearable device STAT-ONTM	12 months
Change from baseline in symptomatic PD medication at 12 month time period	Change from baseline in symptomatic PD medication (Levodopa equivalent dose) Change from baseline in the number of vaccine specific B- and T cell clones as assessed by B/T cell receptor sequencing	12 months

Collaborators and Investigators

• Sponsor: Tridem Bioscience FlexCo
• Investigators: Study Director: Achim Schneeberger, Dr., Tridem Bioscience FlexCo

Study record dates

Study Major Dates

• Study Start (Actual): July 28, 2026
• Primary Completion (Estimated): December 1, 2026
• Study Completion (Estimated): July 1, 2027

Study Registration Dates

• First Submitted: August 17, 2026
• First Submitted That Met QC Criteria: August 17, 2026
• First Posted (Actual): August 20, 2026

Study Record Updates

• Last Update Posted (Actual): September 10, 2026
• Last Update Submitted That Met QC Criteria: September 7, 2026
• Last Verified: September 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Synucleinopathies; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurodegenerative Diseases; Movement Disorders; Parkinsonian Disorders; Basal Ganglia Diseases; Parkinson Disease
• Other Study ID Numbers: TRB-Boost-001; 2026-526294-42-00 (Ctis)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No