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Efficacy & Safety of Nasal Influenza Immunisation in Children

Efficacy & Safety of Nasal Influenza Immunisation in Children - The SNIFFLE-3 Study

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02549365
Acronym
SNIFFLE-3
Enrollment
276
Registered
2015-09-15
Start date
2015-10-31
Completion date
2016-04-30
Last updated
2019-12-11

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Influenza Vaccines Efficacy and Safety

Brief summary

The UK Departments of Health now recommend annual influenza vaccination for all children 2-7 years of age, with children over 7 years eligible for vaccination if in certain higher risk clinical categories. Though data are available documenting the safety and immunogenicity of LAIV in this age group, there are little data to assess efficacy and immune correlates in UK children, and in particular atopic children. This study will enrol 200 children (and at least 200 unvaccinated household sibling controls), many with a history of asthma or recurrent wheezing, and allow an assessment of efficacy, safety and immune correlates in these children, and how this varies with prior administration of pandemic influenza vaccine and/or LAIV.

Interventions

Administration of LAIV, with subsequent surveillance (nasal swabbing) during influenza season

PROCEDURESurveillance (nasal swabbing) during influenza season

Sponsors

Public Health England
CollaboratorOTHER_GOV
Imperial College London
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
2 Years to 18 Years
Healthy volunteers
Yes

Inclusion criteria

* Aged 2 - 18 years old * Written informed consent from parent/guardian (or patient themselves from age 16 years), with assent from children aged 8 years and above wherever possible.

Exclusion criteria

* Hypersensitivity to the active ingredients, gelatin or gentamicin (a possible trace residue) \[notwithstanding allergy to egg protein\] * Previous systemic allergic reaction to LAIV * Previous allergic reaction to an influenza vaccine (not LAIV) is a relative contra-indication, which must be discussed with the site PI to confirm patient suitability * Children/adolescents who are clinically immunodeficient due to conditions or immunosuppressive therapy such as: acute and chronic leukaemias; lymphoma; symptomatic HIV infection; cellular immune deficiencies; and high-dose corticosteroids\*\*. \*\*High-dose steroids is defined as a treatment course for at least one month, equivalent to a dose of prednisolone at 20mg or more per day (any age); or for children under 20kg, a dose of 1mg/kg/day or more. * Children and adolescents younger than 18 years of age receiving salicylate therapy because of the association of Reye's syndrome with salicylates and wild-type influenza infection. * pregnancy * Febrile ≥ 38.0 'C in last 72 hours * Acute wheeze in last 72 hours requiring treatment beyond that normally prescribed for regular use by the child's treating healthcare professional * Recent admission to hospital in last 2 weeks for acute asthma * Current oral steroid for asthma exacerbation or course completed within last 2 weeks * Received any blood or blood products within the past 12 weeks * Any other significant condition or circumstance which, in the opinion of the investigator, may either put the participant at risk because of participation in the study, or may influence the result of the study, or the participant's ability to participate in the study.

Design outcomes

Primary

MeasureTime frameDescription
Vaccine EfficacyDuring 2015/2016 influenza season - precise dates to be set by Public Health England as this varies annually. Approximate duration of 3 monthsVaccine efficacy will be assessed through documentation of the incidence of laboratory confirmed influenza and other respiratory viruses in the children receiving LAIV compared to unvaccinated sibling controls

Secondary

MeasureTime frameDescription
Immune Response to LAIVUp to 6 weeks following administration of a single dose of LAIVTo assess the immune response to vaccine and non-vaccine influenza strains before and after a single dose of LAIV administration, with respect to i. serological measures (haemagglutination inhibition titre to specific influenza strain) ii. change in specific nasal IgA responses
Incidence of Adverse Events (AE) and Serious Adverse Events (SAEs) in Those Received LAIVUp to 1 month after LAIV administrationIncidence of adverse events (AE) and serious adverse events (SAEs) in children receiving LAIV, with the following sub-analyses: * AEs occurring up to 72 hours after LAIV in participants with a history of atopy / asthma / recurrent wheezing, compared to non-atopic participants. * Wheezing / asthma symptoms in subjects given LAIV who have a past medical history of asthma or recurrent wheeze in the 4 weeks prior to vaccine administration vs the 3-4 week period after LAIV. NB: AE data was NOT collected in household controls, as per protocol NB: AE delay not collected in Controls (as per protocol)

Countries

United Kingdom

Participant flow

Participants by arm

ArmCount
Intervention
Administration of Live attenuated influenza vaccine (LAIV) as per national guidance. Surveillance thereafter through nasal swabbing in the event of influenza-like illness. Live attenuated influenza vaccine: Administration of LAIV, with subsequent surveillance (nasal swabbing) during influenza season Surveillance (nasal swabbing) during influenza season
164
Controls
Surveillance in siblings of participants in the Intervention arm, through nasal swabbing in the event of influenza-like illness, irrespective of their vaccination status. Surveillance (nasal swabbing) during influenza season
112
Total276

Baseline characteristics

CharacteristicInterventionControlsTotal
Age, Categorical
<=18 years
164 Participants112 Participants276 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
0 Participants0 Participants0 Participants
Race and Ethnicity Not Collected0 Participants
Region of Enrollment
United Kingdom
164 Participants112 Participants276 Participants
Sex: Female, Male
Female
65 Participants48 Participants113 Participants
Sex: Female, Male
Male
99 Participants64 Participants163 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
— / —
other
Total, other adverse events
43 / 164
serious
Total, serious adverse events
0 / 164

Outcome results

Primary

Vaccine Efficacy

Vaccine efficacy will be assessed through documentation of the incidence of laboratory confirmed influenza and other respiratory viruses in the children receiving LAIV compared to unvaccinated sibling controls

Time frame: During 2015/2016 influenza season - precise dates to be set by Public Health England as this varies annually. Approximate duration of 3 months

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
InterventionVaccine EfficacySwab positive for H1N14 Participants
InterventionVaccine EfficacyNo swab taken as not indicated135 Participants
InterventionVaccine EfficacySwab positive for 'flu B4 Participants
InterventionVaccine EfficacySwab negative21 Participants
ControlsVaccine EfficacyNo swab taken as not indicated95 Participants
ControlsVaccine EfficacySwab negative15 Participants
ControlsVaccine EfficacySwab positive for 'flu B0 Participants
ControlsVaccine EfficacySwab positive for H1N12 Participants
95% CI: [0.6, 13.9]
Secondary

Immune Response to LAIV

To assess the immune response to vaccine and non-vaccine influenza strains before and after a single dose of LAIV administration, with respect to i. serological measures (haemagglutination inhibition titre to specific influenza strain) ii. change in specific nasal IgA responses

Time frame: Up to 6 weeks following administration of a single dose of LAIV

Population: 39 patients provided paired blood samples pre and post LAIV 89 patients provided paired oral fluid samples pre/post LAIV

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
InterventionImmune Response to LAIV>4-fold increase in HI titre to a_cal strain1 Participants
InterventionImmune Response to LAIV>4-fold increase in HI titre to a_swiss strain19 Participants
InterventionImmune Response to LAIV>4-fold increase in HI titre to a_eng strain4 Participants
InterventionImmune Response to LAIV>4-fold increase in HI titre to b_phu strain9 Participants
InterventionImmune Response to LAIV>4-fold increase in HI titre to b_bris strain11 Participants
InterventionImmune Response to LAIV>4-fold increase in oral fluid IgA to h16 Participants
InterventionImmune Response to LAIV>4-fold increase in oral fluid IgA to h319 Participants
Secondary

Incidence of Adverse Events (AE) and Serious Adverse Events (SAEs) in Those Received LAIV

Incidence of adverse events (AE) and serious adverse events (SAEs) in children receiving LAIV, with the following sub-analyses: * AEs occurring up to 72 hours after LAIV in participants with a history of atopy / asthma / recurrent wheezing, compared to non-atopic participants. * Wheezing / asthma symptoms in subjects given LAIV who have a past medical history of asthma or recurrent wheeze in the 4 weeks prior to vaccine administration vs the 3-4 week period after LAIV. NB: AE data was NOT collected in household controls, as per protocol NB: AE delay not collected in Controls (as per protocol)

Time frame: Up to 1 month after LAIV administration

Population: AE data was not collected in household controls, as per protocol

ArmMeasureCategoryValue (COUNT_OF_PARTICIPANTS)
InterventionIncidence of Adverse Events (AE) and Serious Adverse Events (SAEs) in Those Received LAIVSAE0 Participants
InterventionIncidence of Adverse Events (AE) and Serious Adverse Events (SAEs) in Those Received LAIVAE63 Participants
InterventionIncidence of Adverse Events (AE) and Serious Adverse Events (SAEs) in Those Received LAIVNo AEFI reported101 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026