CompletedPhase 2

Humoral and Cellular Immunity for TBE Vaccination in Allogeneic HSCT Recipients

Austria34 participantsStarted 2014-07

Plain-language summary

Patients undergoing allogeneic blood and marrow transplantation (HSCT) experience a prolonged period of dysfunctional immunity. Systematic reimmunization is necessary at appropriate time intervals following transplantation to re-establish immunity. Vaccination practices after HSCT remain varied and data sparse. Tick-borne encephalitis (TBE) is one of the most severe infections of the central nervous system caused by a tick-borne flavivirus. There is no specific treatment, and prevention with the vaccine is the only intervention available. To assess the efficacy of TBE vaccination in adult allogeneic HSCT recipients compared to an age-matched and sex-matched control group of healthy volunteers without previous TBE vaccination, a prospective open-label phase II pilot study on humoral and cellular immune responses after use of TBE vaccine (FSME Immun) will be performed. As primary end point the outcome of the neutralization test (NT) against TBE will be assessed in a total of 26 HSCT patients one year after HSCT and in 26 healthy volunteers, namely four weeks after the second vaccination. Therefore, the number of subjects with NT titres against TBE virus \>10, assumed to be the threshold for antibody-mediated protection will be evaluated. As secondary endpoints, antibody concentrations of TBE enzyme-linked immunosorbent assay before and four weeks after the second and third vaccination and antibody concentrations of NT against TBE four weeks after primary immunization. To evaluate cellular immune responses, lymphocyte proliferations assays and cytokine detection assays will be performed. In a subgroup analysis, these secondary endpoints will be compared between healthy volunteers, HSCT patients without immunosuppressive treatment and HSCT patients receiving immunosuppressive agents. Additionally, immune reconstitution by analysis of peripheral blood lymphocyte subsets and serum immunoglobulin levels will be evaluated prior to vaccination, after twelve weeks and prior to the third vaccination in HSCT patients only.

Who can participate

Age range

18 Years

Sex

ALL

See this in plain English?

AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.

Inclusion Criteria: * Male and female subjects will be eligible for participation in this study if they: * Are ≥18 years on the day of screening * Had undergone an allogeneic HSCT 11 to 13 months ago (study population) * Are clinical healthy without previous TBE vaccination (control group) * Have an understanding of the study, agree to its provisions, and give written informed consent prior to study entry * If female and capable of bearing children - have a negative urine pregnancy test result at study entry and agree to employ adequate birth control measures for the duration of the study Exclusion Criteria: * Subjects will be excluded from participation in this study if they: * Have received a TBE vaccination following HSCT * Suffer from extremely severe acute graft-versus host disease and therefore receive prednisone \>0.5 mg/kg bodyweight as part of a combination therapy or a three agent immunosuppressive treatment (because in these HSCT patients any type of vaccination has to be postponed until immunosuppression is reduced to a double combination or prednisone \<0.5 mg/kg bodyweight) * Suffer from or have a history of previous TBE virus infection or vaccination, previous dengue virus infection or vaccination against yellow fever or Japanese encephalitis * Have any acute febrile illness in the 2 weeks prior to or at the time of enrolment * Have a history of severe allergic reactions or anaphylaxis after vaccination * If female, are pregnant or la…

Questions worth asking your doctor

Bring these to your next appointment. They're a starting point for a shared conversation — not a sign you qualify or a recommendation to enrol.

1Based on my diagnosis and history, is this trial worth exploring for me — or is there a standard treatment we should try first?
2What does this trial's phase tell us about how much is already known about its safety and benefit?
3What would taking part actually involve for me — visits, tests, time, and travel?
4What are the known and possible risks or side effects I should weigh, and how would they be monitored?
5If this trial isn't the right fit, what other options or trials would you suggest I look into?

Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.

Questions for the trial coordinator

The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.

1What does taking part actually involve week to week — how many visits, where, and how long does each one take?
2What costs are covered by the study, and what might I have to pay for myself, including travel, parking, or time off work?
3What happens during screening, and what happens if the study team confirms I don't meet the criteria after those tests?
4Who pays for the scans, blood work, and other tests the trial requires — the study, my insurance, or me?
5How will being in the trial affect my regular care, and will my own doctor stay informed and involved?
6Can I leave the trial at any point if I change my mind, and what would happen to my care if I do?

A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.

What they're measuring

Outcome of the Neutralization Test (Number of Subjects With Antibody Response Measured by Neutralization Assay)

Timeframe: four weeks after the second vaccination

Trial details

NCT IDNCT01991067

SponsorMedical University of Vienna

Sponsor typeOTHER

Study typeINTERVENTIONAL

Primary completion2018-10-28

Results submitted2020-06-26

View on ClinicalTrials.gov More Tick Borne Encephalitis trials