Immune response to infuenza vaccine in young children
Conditions
Interventions
Sponsors
Eligibility
Inclusion criteria
Inclusion criteria: 1) Healthy children or children with well-controlled pre-existing medical conditions (as concluded from the medical history with a stable regimen for at least 2 weeks prior to study entry , physical examination, and clinical judgment) age range = 3 and = 11 years old. 2) Signed informed consent from parents/guardians. 3) Parents/guardians able to understand and comply with the study protocol requirements, including availability for all scheduled visits of the study. Are the trial subjects under 18? yes Number of subjects for this age range: 50 F.1.2 Adults (18-64 years) no F.1.2.1 Number of subjects for this age range F.1.3 Elderly (>=65 years) no F.1.3.1 Number of subjects for this age range
Exclusion criteria
Exclusion criteria: 1) Acute illness, at the time of study vaccine administration (once acute illness is resolved, participants will be re-revaluated for eligibility). 2) Recorded fever (for eligibility purpose defined as a body temperature greater than 37.5°C) within 3 days prior to study vaccine administration (once fever/acute illness is resolved, participants will be re-evaluated for eligibility by the investigator). 3) Current or previous, laboratory confirmed case of influenza during the past 6 months, based on anamnesis or medical record (if available) at screening visit. 4) Household contact with and/or intimate exposure to an individual with any laboratory confirmed influenza infection during the past 6 months prior to vaccination. 5) History of severe allergic reactions after previous vaccinations or hypersensitivity to any study vaccine components (ovalbumin, egg proteins), neomycin, formaldehyde or octoxynol-9. 6) Previous history of Guillain Barré Syndrome. 7) Any confirmed or suspected condition with impaired/altered function of immune system (e.g. immunodeficient or autoimmune conditions). 8) Having any bleeding disorder which is considered as a contraindication to intramuscular injection or blood draw according to the opinion of the investigator 9) Chronic administration (defined as more than 14 days) of immunosuppressant or other immune-modifying drugs within three months prior to the study vaccination or planned use throughout the study period. (For corticosteroids, this means prednisone, or equivalent, = 0.5 mg/kg per day. Inhaled, intranasal and topical steroids are allowed. 10) Neoplastic disease or any hematologic malignancy (except localized skin or prostate cancer that is stable at the time of vaccination in the absence of therapy and subjects who have a history of neoplastic disease and have been disease-free for =5 years). 11) Administration of blood, blood products and/or plasma derivatives or any parenteral immunoglobulin preparation in the past 3 months or planned use throughout the study period. 12) Administration of any vaccine within 28 days prior to enrolment in the study or planned administration of any vaccine during study participation. 13) Use of any investigational or non-registered drug or vaccine within 30 days prior to the administration of study vaccines or planned during the study. 14) Having received systemic antibiotic treatment within 3 days prior to enrolment. 15) Acute or chronic, clinically significant pulmonary, cardiovascular, metabolic, neurological, hepatic, or renal functional abnormality, as determined by medical history or physical examination if uncontrolled or without appropriate treatment 16) Any other condition that in the opinion of the investigator would jeopardize the safety or rights of the volunteer participating in the study or make it unlikely that the participant could complete the protocol. For the second vaccine dose the exclusion criteria are: 1) Previous influenza vaccination before study start, as these children only require one vaccination. 2) Acute illness, at the time of study vaccine administration (once acute illness is resolved, participants will be re-revaluated for eligibility). 3) Recorded fever (for eligibility purpose defined as a body temperature greater than 37.5°C) within 3 days prior to study vaccine administration (once fever/acute illness is resolved, participants will be re-evaluated for eligibility by the investigator). 4) History of severe allergic reactions
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Main Objective: •To measure the level of the immune response (HAI titres) after two intramuscular doses of the quadrivalent inactivated influenza vaccine (Vaxigrip Tetra) in mainly healthy children aged 3-11 years old. ;Secondary Objective: Secondary Objectives •To measure the levels, avidity, biophysical characteristics and functionality of influenza-specific antibodies induced by the vaccine ;Primary end point(s): •HAI antibody titres on D0 and D58 •Proportion of participants with HAI titres = 40 at D58 •HAI antibody titres fold increase between D0 and D58 Proportion of participants with Seroconversion (titre < 10 at D0 and post-vaccination titre = 40 at D30 (one dose) or D58 (two dose), or titre = 10 at D0 and a = 4-fold increase in titre ;Timepoint(s) of evaluation of this end point: day 58 after first vaccination dose (for two doses) / day 30 (for one dose) | — |
Secondary
| Measure | Time frame |
|---|---|
| Secondary end point(s): secondary endpoints a) Neutralizing antibody titres will be measured for each vaccine strain with the microneutralization (MN) assay. The analyses will be performed on blood samples obtained on D0, D30 and D58. • Individual MN antibody titre on D0, D30 and D58 • Detectable MN (MN antibody titre = 10 at D0, D30, D58 • Proportion of participants with MN antibody titres = 20, = 40, = 80) at D30, D58 • Individual MN antibody titre fold-increase D30 and D58 post-vaccination relative to D0 • Fold-increase in MN antibody titre [D58/D0] or [D30/D0] = 2 and = 4 b) Anti-Haemagglutinin (HA) and Neuraminidase (NA) antibody titres to vaccine strain and antibody avidity. • Individual HA and NA antibody titres on D0, D30 and D58 • Detectable HA and NA antibody titre = 10 at D0, D30 and D58 • Proportion of participants with HA and NA antibody titres = 20, = 40, = 80 at D30 and D58 • Individual HA and NA antibody titre ratio (D58/ D0) (D30/ D0) • Fold-increase in HA and NA antibody titre [post/pre] = 2 and = 4 at D30 and D58 • Avidity index of HA and NA antibody at D0, D30 and D58 c) Level (mean fluorescence intensity) and avidity (avidity index) of influenza-specific antibody isotypes at D0, D30 and D58 d) Level of influenza-specific antibody isotypes triggering Fc-dependent effector functions (proportion of activated cells, phagocytic score or mean fluorescence intensity) at D0, D30 and D58 ;Timepoint(s) of evaluation of this end point: Day 30, Day 58 post vaccination | — |
Countries
Norway
Contacts
Helse Bergen HF