Mucosal and Systemic Immune Responses Induced by an Intranasal Influenza Live Attenuated Vaccine

NCT07232745 | Active Not Recruiting Phase 4

• 1 other identifier: JSJKYMS002
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

This is a single-center, open-label, single-arm clinical trial designed to evaluate the mucosal and systemic immune responses induced by an intranasal influenza live attenuated vaccine, and to explore the correlation between the two. The study plans to recruit 60 healthy volunteers aged 14-17 years, with a male-to-female ratio of 1:1. Participants and their guardians must be able and willing to comply with the clinical trial protocol and provide informed consent. Eligible participants will receive a single 0.2 mL dose of LAIV prior to the influenza season. Information on participants' historical vaccination records, baseline demographic data, and past health status will be collected. Nasal specimens (nasal secretions and nasal mucosal cells) and blood samples (serum and PBMCs) will be collected on Day 0 (before vaccination), Day 7, and Day 28 after vaccination for transcriptome sequencing and immunogenicity analysis. In addition, fecal samples will be collected on Day 0 (before vaccination), Day 7, and Day 28 after vaccination for intestinal microbiota detection.

Conditions

Influenza

Keywords

Systemic Immunity; Mucosal Immunity; Intranasal Influenza Live Attenuated Vaccine

Outcome Measures

Primary Outcomes (2)

• The level of IgG antibodies (ng/mL) against the vaccine strain in serum at 28 days post-vaccination.

  Measured by Enzyme-Linked Immunosorbent Assay (ELISA)

  Day 28 post-vaccination

• The level of sIgA antibodies (AU/mL) against the vaccine strain in nasal secretions at 28 days post-vaccination.

  Measured by Enzyme-Linked Immunosorbent Assay (ELISA)

  Day 28 post-vaccination

Secondary Outcomes (11)

• The levels of cytokines in serum at 7 days post-vaccination.

  Day 7 post-vaccination

• The levels of cytokines in nasal mucosal secretions at 7 days post-vaccination.

  Day 7 post-vaccination

• The levels of cytokines in serum at 28 days post-vaccination.

  Day 28 post-vaccination

• The levels of cytokines in nasal mucosal secretions at 28 days post-vaccination.

  Day 28 post-vaccination

• The level of IgG antibodies (ng/mL) against the vaccine strain in serum at 7 days post-vaccination.

  Day 7 post-vaccination

Other Outcomes (2)

• Changes in the abundance of intestinal microbiota compared with baseline (Exploratory).

  Day 28 post-vaccination

• Changes in the levels of fecal or serum metabolites compared with baseline (Exploratory)

  Day 28 post-vaccination

Study Arms (1)

The vaccination group (Self-Controlled)

EXPERIMENTAL

Biological: LAIV

Interventions

LAIV BIOLOGICAL

This vaccine is produced by Changchun BCHT Biotechnology Co.

The vaccination group (Self-Controlled)

Eligibility Criteria

• Age: 14 Years - 17 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Child (0-17)

You may qualify if:

• Individuals aged 14-17 years.
• Volunteers and their guardians are able and willing to comply with the requirements of the clinical trial protocol and sign the informed consent form.

You may not qualify if:

• Allergy to any component of the vaccine product, including eggs, excipients, or gentamicin sulfate.
• Individuals with acute illnesses, severe chronic illnesses, acute exacerbations of chronic illnesses, or fever.
• Pregnant or lactating women.
• Individuals with Leigh syndrome who are receiving treatment with aspirin or aspirin-containing medications.
• Individuals with immunodeficiency, immunosuppression, or those undergoing immunosuppressive therapy.
• Individuals with uncontrolled epilepsy, other progressive neurological disorders, or a history of Guillain-Barré syndrome.
• Individuals with rhinitis or asthma.
• Individuals with a personal or family history of seizures, chronic diseases, epilepsy, or allergic tendencies.
• Individuals who have received immunoglobulin injections within the last 3 months prior to vaccination.
• Individuals who have used other live attenuated vaccines within 1 month prior to vaccination.
• Individuals planning to use antiviral drugs for influenza within 48 hours before or 2 weeks after vaccination.
• Individuals planning to use any other intranasal medication within 2 days after vaccination.
• Subjects with underlying gastrointestinal diseases, including but not limited to inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), chronic diarrhea, peptic ulcer, and intestinal polyps.
• Subjects with metabolic diseases, such as diabetes mellitus, obesity (BMI ≥ 25.9 kg/m²), hyperlipidemia, or metabolic syndrome.
• Subjects who have used antibiotics, probiotics, or other drugs that may affect the intestinal microbiota within the past 3 months.

Sponsors & Collaborators

• Jiangsu Province Centers for Disease Control and Prevention: lead

Study Sites (1)

Haizhou District Center for Disease Control and Prevention

Lianyungang, Jiangsu, China

Location

MeSH Terms

Conditions

Influenza, Human

Condition Hierarchy (Ancestors)

Respiratory Tract Infections; Infections; Orthomyxoviridae Infections; RNA Virus Infections; Virus Diseases; Respiratory Tract Diseases

Study Officials

• Jing-Xin Li, PhD

  Jiangsu Provincial Center for Diseases Control and Prevention

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: NETWORK
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 14, 2025
• First Posted: November 18, 2025
• Study Start: October 12, 2025
• Primary Completion: November 10, 2025
• Study Completion (Estimated): May 10, 2026
• Last Updated: November 18, 2025

Record last verified: 2025-10

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)