A Phase 1 interventional study of Human monoclonal antibody TBE025, intravenous infusion in The Tick-borne Encephalitis Virus (TBEV), sponsored by Giuseppe Pantaleo. Not yet recruiting at 1 site in Switzerland. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-01-29.
Sponsored by Giuseppe Pantaleo · Phase 1, Interventional, and Treatment
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.
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.
51 studies on the registry are indexed under Encephalitis, Tick-Borne; 9 are open to participants now.
This study's planned enrollment of 18 is below the median of 192 across 32 interventional studies indexed under Encephalitis, Tick-Borne.
Browse Encephalitis, Tick-Borne studies →This is the only study on the registry with Giuseppe Pantaleo as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Postmenopausal
Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis C tests
Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.
After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
TBE025 200 mg administered intravenously on Day 0
Drug: Human monoclonal antibody TBE025, intravenous infusion
TBE025 600 mg administered intravenously on Day 0
Drug: Human monoclonal antibody TBE025, intravenous infusion
TBE025 2000 mg administered intravenously on Day 0
Drug: Human monoclonal antibody TBE025, intravenous infusion
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.
Maximum Tolerated Dose (MTD) of TBE025
Number and percentage of subjects experiencing AEs, SAEs, AEs related to investigational product at each dose level
Time frame: 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
Time frame: 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.
Time frame: Up to 21 days after the infusion.
Pharmacokinetic profile of TBE025
Plasma concentration measured by ELISA for each participant at each dose level
Time frame: up to 84 days after infusion
Presence of anti-drug antibodies
Antibodies against TBE025 measured by ELISA for each participant at each dose group
Time frame: Up to 84 days after infusion
Plan to share: 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.
No publications or documents are linked to this record.
Start is estimated for Jan 2026; primary completion for May 2026, 4 months later.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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