Studying the LAIV induced Immune respOnse in the Nasopharynx of young children.

Overview

Sponsor-declared trial summary

Key facts

Sponsor

Leids Universitair Medisch Centrum (LUMC)

Participant type

Pediatric, Healthy volunteers

Age range

0-17 years

Gender

Male and Female

Therapeutic area

Diseases [C] - Respiratory Tract Diseases [C08]

Trial duration

18 Sep 2025 → ongoing

Decision date (initial)

2025-07-24

Transition trial

No

Low-intervention

Yes

Rare-disease indication

No

Vulnerable population

Yes

Funding sources

EU ERC starting grant

Trial design

CTIS Part I — objectives, methods, condition coding

Main objective

Scope: Others

Identifying mucosal surrogates of protection following intranasal LAIV in children. Shedding of the LAIV is used as a surrogate for susceptibility to infection, with the expectation that the first dose of LAIV induces variable levels of immunity that confer protection against shedding of the second dose.

Secondary objectives 7

1. To study the LAIV shedding kinetics
2. To study the strain specific mucosal antibody response.
3. To study the mucosal immune response.
4. To study potential changes in microbiome composition after LAIV challenge.
5. To study systemic immune response.
6. To compare influenza specific antibody response in serum and nasal mucosa.
7. To associate common cold symptoms with LAIV administration and related host responses.

Conditions and MedDRA coding

Influenza

Eligibility criteria

Principal inclusion / exclusion criteria as submitted by sponsor

Inclusion criteria 2

1. Age between two and seven years old
2. Parents ability and willingness to adhere to protocol-specified procedures, including availability of a freezer at home to store samples. Donating blood is optional as this is a secondary endpoint.

Exclusion criteria 4

1. Recipient of any influenza vaccine (both LAIV or IIV) in the same or a previous flu-season.
2. Recipient of any other vaccine within one month prior to inclusion-date.
3. Meeting one or more contraindications for the Fluenz vaccine as stated in paragraph 6.3 of the protocol.
4. Substantial language barrier of either potential subject or parent. Participants and their parents are asked to self-collect samples during this trial, therefore instructions need be given and adequately understood.

Endpoints

Primary and secondary outcome measures (English text)

Primary endpoints 1

1. Presence or absence of viral shedding of vaccine-strains after first and second dose of LAIV in nasal lining fluid, collected using nasosorptions and analyzed with RT-qPCR.

Secondary endpoints 7

1. LAIV shedding kinetics (density and duration) during first and second dose of LAIV, measured in nasal lining fluid using nasosorptions and analyzed with RT-qPCR.
2. Change in influenza specific mucosal antibodies (including IgA) in nasal lining fluid before and after first and second dose of LAIV. Measured in nasal lining fluid from nasosorptions and analyzed for binding and/or functional capacity.
3. Nasal immune responses during LAIV, with soluble proteins measured in nasal lining fluid from nasosorption samples.
4. Nasal colonization and infection dynamics by other URT bacteria and viruses, comparing composition before and after LAIV. Samples will be collected using nasosorptions and analyzed with molecular methods.
5. Analysis of peripheral immune system in whole blood collected at baseline and 28 days post LAIV dose 1. Measured using tools such as spectral flow cytometry.
6. Serum and mucosal IgG and IgA post-LAIV, comparing baseline to day 28 post-LAIV. Measured through binding and functional assays.
7. Correlating immune responses and shedding kinetics with data from baseline questionnaire and daily questionnaires assessing RTI-related symptoms. Collected using electronic recordings.

Investigational products

Investigational medicinal products (IMPs), comparators, placebo, auxiliary

Test 1

Sponsors and contacts

Sponsor organisations, regulatory contacts, third parties

Leids Universitair Medisch Centrum (LUMC)

Sponsor organisation

Leids Universitair Medisch Centrum (LUMC)

Address

Albinusdreef 2

City

Leiden

Postcode

2333 ZA

Country

Netherlands

Scientific contact point

Organisation

Leids Universitair Medisch Centrum (LUMC)

Contact name

Maurits Thomas Wulffraat

Public contact point

Organisation

Leids Universitair Medisch Centrum (LUMC)

Contact name

Maurits Thomas Wulffraat

Locations

1 EU/EEA country · 1 investigational sites

By country

Investigational sites

Country notifications

Trial-start, recruitment-start, end and early-termination notifications submitted per Member State

Results and documents

Annex IV summary of results, Annex V layperson summary, and all documents registered in CTIS for this trial

Documents 16 files

Public protocol annexes, IB summaries, regulatory submissions and post-authorisation documents registered in CTIS.

Application history

1 submissions — initial application plus substantial / non-substantial modifications