Ad26.ZEBOV Booster in Children Previously Vaccinated With Ad26.ZEBOV and MVA-BN-Filo (EBOVAC Booster Study)
Condition: Ebola Virus Disease
MeSH terms: Virus Diseases; Hemorrhagic Fever, Ebola
Intervention: Ad26.ZEBOV booster vaccination, given at a dose of 5x10^10 vp, via IM injection
Intervention description: Ad26.ZEBOV is a monovalent, replication-incompetent adenovirus serotype 26-based vector that expresses the full-length Ebola virus Mayinga glycoprotein
Phase: Phase 2
Study type: Interventional
Primary purpose: Prevention
Intervention model: Single Group Assignment
Intervention model description: All participants will receive a single dose of Ad26.ZEBOV at a dose of 5x10^10 viral particles (vp) administered intramuscularly.
Masking: None (Open Label)
Enrollment: 50.0
Sex: All
Minimum age: 3 Years
Maximum age: 16 Years
Healthy volunteers: Accepts Healthy Volunteers
Keywords: Ad26.ZEBOV; booster vaccination; children

Summary:

      This is an open-label study evaluating the safety and immunogenicity of a booster dose of
      Ad26.ZEBOV administered to children who were previously vaccinated with Ad26.ZEBOV followed
      by MVA-BN-Filo 56 days later.
    

Eligibility criteria:

        Inclusion Criteria:

          1. Child must be enrolled in the VAC52150EBL3005 (EBOVAC-Salone Extension) study but not
             in the immunogenicity subset of EBOVAC-Salone Extension study.

          2. Child must be a former participant in the VAC52150EBL3001 (EBOVAC-Salone) trial, and
             have received Ad26.ZEBOV (dose 1) vaccination followed by the MVA-BN-Filo (dose 2)
             vaccination within the EBOVAC- Salone trial window for dose 2 vaccination.

          3. Child must have been aged 1 to 11 years old at the time of dose 1 vaccination in the
             EBOVAC-Salone trial.

          4. The parent/guardian must consent for their child to participate in the VAC52150EBL2011
             study. Children aged 7 years and older will be asked to give positive assent for their
             participation in the study.

          5. The parent/guardian is willing/able to ensure that their child adheres to the
             prohibitions and restrictions specified in this protocol.

          6. Child must be healthy in the investigator's clinical judgement (and the
             parent/guardian's judgement) on the basis of medical history, physical examination,
             vital signs, and a haematological assessment (i.e. full blood count) performed at
             screening. Subjects must meet the following haematology parameters within 28 days
             before Day 1:

               -  Haemoglobin ≥8.0 g/dL for children aged 1 to <5 years, ≥9g/dL for children aged 5
                  or older

               -  Platelet count ≥100 x 10^9/L

               -  White blood cell count ≥5.0 x 10^9/L

          7. Adolescent girls who have started their menstrual periods and/or are ≥12 years of age
             at the time of screening, must have a negative urine β-hCG pregnancy test at screening
             and immediately prior to the booster vaccination on Day 1.

          8. The parent/guardian is available and willing to have their infant participate for the
             duration of the study visits.

          9. The parent/guardian must have a means to be contacted.

         10. The parent/guardian must pass the Test of Understanding (TOU)

        Exclusion Criteria:

          1. Participants in the EBOVAC-Salone trial who were allocated to the control arm
             receiving the WHO- prequalified Meningococcal Group A, C, W135 and Y conjugate
             vaccine.

          2. Participants in the EBOVAC-Salone trial who were age 12 years and older at the time of
             dose 1 vaccination.

          3. Known allergy or history of anaphylaxis or other serious adverse reactions to vaccines
             or vaccine products (including any of the constituents of the study vaccine, e.g.,
             polysorbate 80, ethylenediaminetetraacetic acid or L-histidine for Ad26.ZEBOV
             vaccine), including known allergy to chicken or egg proteins and aminoglycosides
             (gentamicin).

          4. Presence of acute illness (this does not include minor illnesses such as mild
             diarrhoea or mild upper respiratory tract infection) or axillary temperature ≥38C on
             Day 1. Participants with such symptoms will be excluded from enrolment at that time
             but may be rescheduled for enrolment at a later date within the screening window.

          5. Clinically significant history of skin disorder (e.g., psoriasis, contact dermatitis),
             allergy, symptomatic immunodeficiency, cardiovascular disease, respiratory disease,
             endocrine disorder, liver disease, renal disease, gastrointestinal disease,
             neurological illness as judged by the investigator or other delegated individual.

          6. Adolescent girls who are known to be pregnant or breastfeeding at screening.

          7. Received a blood transfusion or other blood products within 8 weeks of vaccination
             day.

          8. Children who have been vaccinated with live-attenuated vaccines within 30 days before
             the study vaccination, and with inactivated vaccine within 15 days before the study
             vaccination.

          9. Children who, in the opinion of the investigator, are unlikely to adhere to the
             requirements of the study or are unlikely to complete the vaccination and observation.

         10. Any other finding which in the opinion of the investigator or other delegated
             individual would increase the risk of an adverse outcome from participation in the
             study.