Induction of Immunity Against Measles in Pediatric Liver Transplant Recipients

Study Overview
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Brief Summary
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Measles is a vaccine-preventable disease, which can be life-threatening in immunosuppressed children. Currently, measles vaccine is not recommended in pediatric orthotopic liver transplant recipients, because it is a live-attenuated vaccine. We want to assess the influence of immunosuppression on immunity against measles in previously vaccinated children and to evaluate the induction of B cell and T cell response against measles elicited by vaccination in children at least 12 months after transplantation.

Detailed Description
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Eligible children in Group 2 will receive a standard dose (0.5 ml) of MMR vaccine during the first medical visit (V1). The lot number and the expiration date will both be recorded on the patient's case report form (CRF). A serological evaluation 4-8 weeks after MMR will identify children requiring an additional dose given 1-2 months apart, as currently recommended for subjects 1 year-old or with limited immune competence (i.e. HIV-infected children). Serological evaluation 4-8 weeks after the second dose or at the one-year follow-up will identify eventual non-responder requiring a third dose. Three will be the maximal number of administrated dose according to this protocol. The persistence of measles-specific antibodies will be assessed yearly, when patients come for their routine visit to the transplant center. Children who do not need MMR immunization because of protective levels will be monitored yearly for maintenance of antibody levels during routine yearly visits/ blood samplings and will not have further intervention.

Official Title
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Induction and Maintenance of Immunity Against Measles in Pediatric Orthotopic Liver Transplantation Recipients: a Prospective Nationwide Study in Switzerland

Conditions
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Measles

Intervention / Treatment
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* Biological: MMR vaccination


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 12 months Measles-specific IgG antibodies negative (<0.2 IU/L), as detected by the routine ELISA assay ≥ 12 months from the time of transplantation and ≥ 2 months from the time of an acute rejection episode Steroids < 2 mg/kg/day, tacrolimus < 0.3mg/kg/day and tacrolimus level < 8 ng/ml for > 1 month. Total lymphocyte count ≥ 750 cells/ul at time of immunization Exclusion Criteria: Known wild-type measles exposure during the last four weeks Measles-containing immunoglobulins administered within the 5 months preceding the measles vaccine. If the child receives measles-containing Ig before an additional dose of MMR vaccine, he/she will be withdrawn from the study Antiviral agents administered during the last four weeks Febrile illness (>38.5°) in the 72 hours before vaccine administration Chronic aspirin therapy Any other immunization with a live-attenuated vaccine during the last four weeks Pregnancy

Ages Eligible for Study
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Minimum Age: 12 Months
Maximum Age: 20 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: MMR vaccination<br>MMR vaccine to seronegative pediatric SOT recipients | Biological: MMR vaccination<br>* Unprotected children will be vaccinated with two MMR vaccines<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| serologic response to MMR vaccine in seronegative transplant recipients | Pediatric transplant recipients will be vaccinated with MMR vaccine (previously seronegative) and their seroresponse will be measured 2 months later | 2 months after vaccination | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Persistance of seroresponse to MMR vaccine | Seroresponse to MMR vaccine will be followed over time in pediatric transplant recipients | 3 years | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Measles, Mumps, Rubella, Pediatric, Solid-organ transplant, serology, vaccine