The Tick-borne Encephalitis Virus (TBEV)Phase 1SVRI01NCT07377253
First-in-Human Study Testing a New Antibody Treatment for Tick-Borne Encephalitis in Healthy Volunteers.
A Phase 1 study testing Human monoclonal antibody TBE025, intravenous infusion in people with The Tick-borne Encephalitis Virus (TBEV), run by Giuseppe Pantaleo at 1 site in Switzerland.
Trial summary
The goal of this clinical trial is to evaluate the safety, tolerability, and pharmacokinetics of the investigational monoclonal antibody TBE025 when given intravenously to healthy adult volunteers aged 18 to 55. Read more about this study
- Who is it for?
- Ages 18 to 55 yearsHealthy volunteers can take part
- Conditions the study is for
- The Tick-borne Encephalitis Virus (TBEV)
- What is being tested?
- Human monoclonal antibody TBE025, intravenous infusion
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 18 participants
- Where
- 1 siteSwitzerland
- Study dates
- 1 Jan 2026to 31 Oct 2026
- Phase
- Phase 1
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 55 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Adults aged 18 to <55 years
- Good general health (medical history, physical exam, normal labs)
- Written informed consent provided
- Ability to read and understand local language
- Contraception requirements : Women of childbearing potential: negative pregnancy test, surgically sterile, postmenopausal, or using highly effective contraception for 3 months post-infusion. Men: surgically sterile or using highly effective contraception (self or partner) and abstain from sperm donation for 3 months post-infusion.
Who cannot join
- BMI <19 or >30
- Infections: HIV, active hepatitis B (HBsAg), active hepatitis C
- Prior participation in investigational study within 30 days
- History of hypersensitivity to monoclonal antibodies
- Recent surgery or unresolved adverse events
- Active autoimmune disease requiring systemic treatment
Show all 14Show fewer
- Recent use of immunosuppressive agents or immunoglobulins
- Immunodeficiency diagnosis
- Significant cardiovascular events within 6 months
- Live/attenuated vaccines within 28 days
- Major surgery within 28 days
- Pregnancy or breastfeeding
- Professional or private link with the research team
- Any condition judged by the investigator to interfere with safety or study results
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Switzerland1 site
Centre Universitaire Hospitalier Vaudois (CHUV)
Lausanne, Canton of Vaud, 1011
About this study
Official title: A Phase I Study to Investigate the Safety, Tolerability, and Pharmacokinetic Characteristics of Intravenous (IV) Administration of a Human Monoclonal Antibody Against Tick-borne Encephalitis Virus in Healthy Adults.
The goal of this clinical trial is to evaluate the safety, tolerability, and pharmacokinetics of the investigational monoclonal antibody TBE025 when given intravenously to healthy adult volunteers aged 18 to 55.
The study aims to determine the recommended Phase II dose of TBE025 and to assess the incidence and severity of adverse events related to its administration.
There is no comparison group, as this is a single-arm, open-label study. Participants will receive a single intravenous infusion of TBE025 at one of three escalating dose levels, will be monitored for safety with regular clinical and laboratory assessments, and will provide blood samples for pharmacokinetic, anti-drug antibody, and neutralization testing.
Read the detailed description
The tick-borne encephalitis virus (TBEV) is an infection spread by ticks that is becoming more common in Europe, including Switzerland. Currently, there is no specific treatment-care focuses on relieving symptoms. Vaccines exist, but few people get vaccinated, and sometimes the vaccine does not offer full protection. There is therefore a real need for new ways to prevent or treat this disease.
TBE025 is a fully human antibody taken from people who have recovered from TBEV. It can strongly block the virus. In lab studies with mice, TBE025 was able to protect against infection, both when given before exposure and soon after infection. It also appears to be safe, with no harmful effects on other tissues.
This first-in-human study (phase 1) will evaluate intravenous administration of TBE025 in healthy adult volunteers using a standard 3+3 dose-escalation design (200 mg, 600 mg, 2000 mg). Between 3 and 18 participants will be enrolled sequentially across three cohorts. The study is designed to establish the maximum tolerated dose and recommended Phase II dose, as well as to characterize the pharmacokinetics, immunogenicity, and neutralization capacity of TBE025.
Participants will be followed for safety, laboratory, and pharmacokinetic assessments over a three-month period. The study will provide the first clinical data on TBE025 in humans and will inform the design of subsequent efficacy trials in populations at risk of TBEV infection.
- Conditions
- The Tick-borne Encephalitis Virus (TBEV)
- Being tested
- Human monoclonal antibody TBE025, intravenous infusion
- Keywords
- Tick-borne encephalitis, Tick-borne encephalitis virus, Human antibody therapy, Healthy volunteers, Phase I clinical trial, Intravenous administration, Monoclonal antibody
- Medical subject headings
- Encephalitis, Tick-Borne
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Human monoclonal antibody TBE025, intravenous infusionDrug
TBE025 is a recombinant, fully human monoclonal antibody (mAb). It is provided in single-use vials containing 20 mg/mL of protein in 5 mL of buffered solution consisting of 10 mM Histidine, 250 mM Trehalose, 10 mM Methionine, 0.05% Polysorbate 20 and water for injection, at pH 5.5. TBE025 is a clear to opalescent, colorless to brown liquid.
| Study group | Role | What they receive |
|---|---|---|
| Cohort 1 | Experimental | TBE025 200 mg administered intravenously on Day 0 Receives: Drug: Human monoclonal antibody TBE025, intravenous infusion |
| Cohort 2 | Experimental | TBE025 600 mg administered intravenously on Day 0 Receives: Drug: Human monoclonal antibody TBE025, intravenous infusion |
| Cohort 3 | Experimental | TBE025 2000 mg administered intravenously on Day 0 Receives: Drug: Human monoclonal antibody TBE025, intravenous infusion |
What is being measured
The primary outcome is the main question the study is designed to answer.
Maximum Tolerated Dose (MTD) of TBE025
Number and percentage of subjects experiencing AEs, SAEs, AEs related to investigational product at each dose level
Measured: Up to 84 days after the infusion
Incidence and severity of adverse events (AEs)
Number and percentage of subjects experiencing AEs related to investigational product and the severity of the AEs at each dose level
Measured: Up to 84 days after the infusion
Incidence and severity of Dose Limiting Toxicity (DLT)
Number and percentage of participants experiencing DLTs at each dose level.
Measured: Up to 21 days after the infusion.
Secondary outcomes (2)
Pharmacokinetic profile of TBE025
Plasma concentration measured by ELISA for each participant at each dose level
Measured: up to 84 days after infusion
Presence of anti-drug antibodies
Antibodies against TBE025 measured by ELISA for each participant at each dose group
Measured: Up to 84 days after infusion
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted29 Jan 2026
- Study start1 Jan 2026 (estimated)
- Primary completion31 May 2026 (estimated)
- Study completion31 Oct 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for The Tick-borne Encephalitis Virus (TBEV)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Model description
- Phase I, Dose escalation 3+3, Non randomized, Open Label.
- Masking
- None (open label)
- Enrolment
- 18 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Giuseppe Pantaleo
- Sponsor type
- University, hospital or other
- Collaborators
- Rockefeller University
- Responsible party
- Sponsor-investigator, Giuseppe Pantaleo, Centre Hospitalier Universitaire Vaudois
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07377253
- Sponsor's protocol ID
- SVRI01
- Acronym
- SVRI01
- Status last verified
- Jan 2026
- First submitted
- 18 Nov 2025
- Last updated
- 29 Jan 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No: No individual participant data (IPD) will be shared. Only de-identified subject-level data may be provided if requested, and only in accordance with participant informed consent and applicable laws.
Study at a glance
From the registry record, last updated by the sponsor on 29 Jan 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase I Study to Investigate the Safety, Tolerability, and Pharmacokinetic Characteristics of Intravenous (IV) Administration of a Human Monoclonal Antibody Against Tick-borne Encephalitis Virus in Healthy Adults.
- ClinicalTrials.gov ID
- NCT07377253
- Acronym / sponsor ID
- SVRI01 / SVRI01
- Conditions
- The Tick-borne Encephalitis Virus (TBEV)
- Keywords
- Tick-borne encephalitis, Tick-borne encephalitis virus, Human antibody therapy, Healthy volunteers, Phase I clinical trial, Intravenous administration, Monoclonal antibody
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 18 participants (estimated)
- Lead sponsor
- Giuseppe PantaleoUniversity, hospital or other
- Collaborators
- Rockefeller University
- Study start
- 1 Jan 2026 (estimated)
- Primary completion
- 31 May 2026 (estimated)
- Study completion
- 31 Oct 2026 (estimated)
- First posted
- 29 Jan 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The goal of this clinical trial is to evaluate the safety, tolerability, and pharmacokinetics of the investigational monoclonal antibody TBE025 when given intravenously to healthy adult volunteers aged 18 to 55.
The study aims to determine the recommended Phase II dose of TBE025 and to assess the incidence and severity of adverse events related to its administration.
There is no comparison group, as this is a single-arm, open-label study. Participants will receive a single intravenous infusion of TBE025 at one of three escalating dose levels, will be monitored for safety with regular clinical and laboratory assessments, and will provide blood samples for pharmacokinetic, anti-drug antibody, and neutralization testing.
Detailed description
The tick-borne encephalitis virus (TBEV) is an infection spread by ticks that is becoming more common in Europe, including Switzerland. Currently, there is no specific treatment-care focuses on relieving symptoms. Vaccines exist, but few people get vaccinated, and sometimes the vaccine does not offer full protection. There is therefore a real need for new ways to prevent or treat this disease.
TBE025 is a fully human antibody taken from people who have recovered from TBEV. It can strongly block the virus. In lab studies with mice, TBE025 was able to protect against infection, both when given before exposure and soon after infection. It also appears to be safe, with no harmful effects on other tissues.
This first-in-human study (phase 1) will evaluate intravenous administration of TBE025 in healthy adult volunteers using a standard 3+3 dose-escalation design (200 mg, 600 mg, 2000 mg). Between 3 and 18 participants will be enrolled sequentially across three cohorts. The study is designed to establish the maximum tolerated dose and recommended Phase II dose, as well as to characterize the pharmacokinetics, immunogenicity, and neutralization capacity of TBE025.
Participants will be followed for safety, laboratory, and pharmacokinetic assessments over a three-month period. The study will provide the first clinical data on TBE025 in humans and will inform the design of subsequent efficacy trials in populations at risk of TBEV infection.
Study design
- Primary purpose
- Treatment
- Allocation
- Non-randomised
- Intervention model
- Sequential
- Masking
- None (open label)
- Number of arms
- 3
- Model description
- Phase I, Dose escalation 3+3, Non randomized, Open Label.
| Arm | Type | Receives |
|---|---|---|
| Cohort 1 | Experimental | Drug: Human monoclonal antibody TBE025, intravenous infusionTBE025 200 mg administered intravenously on Day 0 |
| Cohort 2 | Experimental | Drug: Human monoclonal antibody TBE025, intravenous infusionTBE025 600 mg administered intravenously on Day 0 |
| Cohort 3 | Experimental | Drug: Human monoclonal antibody TBE025, intravenous infusionTBE025 2000 mg administered intravenously on Day 0 |
Who may qualify
- Ages
- 18 to 55 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Adults aged 18 to <55 years
- Good general health (medical history, physical exam, normal labs)
- Written informed consent provided
- Ability to read and understand local language
- Contraception requirements : Women of childbearing potential: negative pregnancy test, surgically sterile, postmenopausal, or using highly effective contraception for 3 months post-infusion. Men: surgically sterile or using highly effective contraception (self or partner) and abstain from sperm donation for 3 months post-infusion.
Key exclusion criteria (14 listed)
- BMI <19 or >30
- Infections: HIV, active hepatitis B (HBsAg), active hepatitis C
- Prior participation in investigational study within 30 days
- History of hypersensitivity to monoclonal antibodies
- Recent surgery or unresolved adverse events
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Human monoclonal antibody TBE025, intravenous infusionTBE025 is a recombinant, fully human monoclonal antibody (mAb). It is provided in single-use vials containing 20 mg/mL of protein in 5 mL of buffered solution consisting of 10 mM Histidine, 250 mM Trehalose, 10 mM Methionine, 0.05% Polysorbate 20 and water for injection, at pH 5.5. TBE025 is a clear to opalescent, colorless to brown liquid. | Drug | Cohort 1, Cohort 2, Cohort 3 |
Primary outcome
Maximum Tolerated Dose (MTD) of TBE025
Time frame: Up to 84 days after the infusion
Number and percentage of subjects experiencing AEs, SAEs, AEs related to investigational product at each dose level
Incidence and severity of adverse events (AEs)
Time frame: Up to 84 days after the infusion
Number and percentage of subjects experiencing AEs related to investigational product and the severity of the AEs at each dose level
Incidence and severity of Dose Limiting Toxicity (DLT)
Time frame: Up to 21 days after the infusion.
Number and percentage of participants experiencing DLTs at each dose level.
2 secondary outcomes
Pharmacokinetic profile of TBE025
Time frame: up to 84 days after infusion
Presence of anti-drug antibodies
Time frame: Up to 84 days after infusion
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 29 Jan 2026.
- Individual participant dataSharing planned: No. No individual participant data (IPD) will be shared. Only de-identified subject-level data may be provided if requested, and only in accordance with participant informed consent and applicable laws.
Related trials for The Tick-borne Encephalitis Virus (TBEV)
RecruitingObservational study
Burden of Tick-borne Encephalitis and Cost-effectiveness of Vaccination in the Czech Republic
Tick Borne Encephalitis (TBE)
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Human monoclonal antibody TBE025, intravenous infusion in people with The Tick-borne Encephalitis Virus (TBEV), run by Giuseppe Pantaleo at 1 site in Switzerland.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 14 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 29 Jan 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Switzerland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Laura Molinari (+41795560626, laura.molinari@chuv.ch), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Maximum Tolerated Dose (MTD) of TBE025 (time frame: Up to 84 days after the infusion). The study lists 3 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 29 Jan 2026.