Immunosuppression, Organ Transplantation
Conditions
Keywords
organ transplantation, immunosuppression, vaccine, varicella, pediatrics
Brief summary
This study sought to determine the safety of the varicella vaccine pre- and post-transplantation when given to pediatric patients listed for solid organ transplantation. The study assessed the antibody response to a two-dose vaccine regimen and determined the durability of that antibody response at several intervals in the post-transplant period. As a secondary objective, the relationship between antibody titers and different variables were explored
Interventions
BIOLOGICALvaricella vaccine (VARIVAX)
Sponsors
The Hospital for Sick Children
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
9 Months to 18 Years
Healthy volunteers
No
Inclusion criteria
* Children \> 9 months of age and adolescents \< 18 years of age. * Pediatric transplant candidates who are in any of the following categories: 1. listed to receive kidney, liver, heart, lung or other or solid organ transplantation in a Canadian transplant centre 2. not yet officially listed, but are regarded by their physicians as transplant candidates by virtue of their underlying diseases * No clinical history for varicella. * Seronegative for antibodies to VZV except infants 9 - 12 months of age who may be seropositive due to maternal antibodies. * Informed consent obtained
Exclusion criteria
* Previous immunization with varicella vaccine. * Any established immune deficiency (underlying disease or drug induced) or any neoplastic disease * Children on any oral and / or intravenous steroids within 3 months prior to immunization. Children on inhaled corticosteroids in excess of 800 mcg of beclomethasone dipropionate ( or equivalent ) per day. * Any exposure to varicella or herpes zoster in the previous 4 weeks involving household, playmate or hospital contacts. * Inability to delay the transplantation for up to 6 weeks following the last varicella immunization. * Presence of a person at increased risk for varicella infection in direct and unavoidable proximity with the vaccinees ( e.g. an immunocompromised sibling) * Past history of varicella or known positive antibody titer for varicella except infants 9 - 12 months of ages who may be seropositive due to maternal antibodies * Known hypersensitivity to any of the components of the vaccine, including neomycin and gelatin * Patients whose mothers are known to be seronegative and plan to become pregnant in the subsequent three months * Administration of VZIG or any other blood products in the previous six weeks (packed red blood cells excepted). * Any significant infection and/or fever at the time of vaccination * Any patient receiving or planning to receive salicylates in the six weeks after immunization * Any patient who has received any live vaccine for 6 weeks or killed vaccine for 2 weeks prior to or after the scheduled VARIVAX™ vaccination.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Determination of the safety of VARIVAX™ | Up to 6 months | Eligible subjects given a two-dose OMVV pre transplantation were monitored for Adverse Events. AE were monitored for up to six wk after each dose with the assistance of parent diaries. |
| Determination of the proportion immunized who demonstrate seroconversion and maintain humoral immunity seroconversion at 6, 12 and 24 months post-transplantation | up to 12 months | Control antigen was prepared in parallel from uninfected cells. A gpELISA antibody level of \>0.6 gpEU/mL defined seroconversion, and a gpELISA antibody level exceeding 5 gpEU/mL defined seroprotection. |
| Determination of the proportion immunized who demonstrate seroconversion and maintain humoral immunity seroconversion at 6, and 12 months post-transplantation | Up to 12 months | VZV-specific antibodies were measured at Merck Research Laboratories using a previously validated ELISA method that detected antibodies to VZV glycoproteins purified from VZV-infected human fibroblasts. |
Countries
Canada
Outcome results
None listed