Study of the Preventive Effects and Mechanisms of Yeast β-Glucan on Upper Respiratory Tract Infections

NCT07085858 | Not Yet Recruiting

• 1 other identifier: IRB25041502
• Study Type: interventional
• Target: 96
• Locations: 1 country
• Sites: 1

Brief Summary

This study is designed as a randomized, double-blind, placebo-controlled human intervention trial targeting a population of university students with persistent allergic rhinitis (AR) symptoms. The primary objective is to evaluate the preventive effect and underlying mechanisms of yeast β-glucan on upper respiratory tract infections (URTIs), providing scientific evidence for the prophylactic use of prebiotics in high-risk populations. All participants will be stratified by sex and body mass index (BMI), and then randomly assigned to either the yeast β-glucan group or the control group. During the 15-week study period-including a 1-week run-in phase, a 12-week intervention phase, and a 2-week follow-up phase-participants in the intervention group will take two yeast β-glucan capsules daily after meals, while the control group will take two placebo capsules with identical appearance, taste, and packaging. Participants will be monitored daily for the occurrence of URTIs. In the event of an infection, the Wisconsin Upper Respiratory Symptom Survey (WURSS-24) will be used to assess symptom severity and duration. Medication use, including dosage, frequency, and timing, will also be recorded. Weekly follow-ups will assess changes in Total Nasal Symptom Score (TNSS), Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), and adverse events. In addition, participants will undergo comprehensive follow-up assessments at Week 0 and Week 12, including TNSS and RQLQ questionnaires, a 3-day dietary intake survey, anthropometric measurements (e.g., height, weight, body fat percentage), and biological sample collection (blood, urine, and stool samples).

Conditions

Upper Respiratory Tract Infections

Keywords

Upper respiratory tract infections; Yeast β-glucan

Outcome Measures

Primary Outcomes (1)

• Incidence of Upper Respiratory Tract Infections (URTIs)

  From enrollment to the end of intervention at 12 weeks

Secondary Outcomes (14)

• Wisconsin Upper Respiratory Symptom Survey (WURSS-24)

  From the onset of URTI symptoms up to 14 days after symptom onset. (through intervention completion, week 0 to week 12)

• Total Nasal Symptom Score (TNSS)

  Each week through intervention completion (Week 0 to Week 12).

• Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ)

  Each week through intervention completion (Week 0 to Week 12).

• IFN-γ

  Baseline Week 12

• IL-4

  Baseline Week 12

Study Arms (2)

Yeast β-Glucan

EXPERIMENTAL

Participants in the intervention group will take yeast β-glucan capsules daily. Each capsule contains 250 mg of yeast β-glucan, along with an appropriate amount of maltodextrin and silicon dioxide. All participants in the intervention group will take two capsules once daily, swallowed with warm water after meals.

Dietary Supplement: yeast β-glucan

placebo group

PLACEBO COMPARATOR

Participants in the placebo group will take two placebo capsules once daily in the same manner. The placebo capsules are identical to the intervention capsules in form, taste, appearance, and packaging, but contain only maltodextrin and a small amount of silicon dioxide.

Dietary Supplement: placebo

Interventions

yeast β-glucan DIETARY_SUPPLEMENT

Participants in the intervention group will take yeast β-glucan capsules daily. Each capsule contains 250 mg of yeast β-glucan, along with an appropriate amount of maltodextrin and silicon dioxide. All participants in the intervention group will take two capsules once daily, swallowed with warm water after meals.

Yeast β-Glucan

placebo DIETARY_SUPPLEMENT

Participants in the placebo group will take two placebo capsules once daily in the same manner. The placebo capsules are identical to the intervention capsules in form, taste, appearance, and packaging, but contain only maltodextrin and a small amount of silicon dioxide.

placebo group

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Aged between 18 and 35 years;
• Meeting the symptom criteria for persistent allergic rhinitis (AR) as defined in the Chinese Guidelines for Diagnosis and Treatment of Allergic Rhinitis (2022, Revised Edition): (1) Symptoms: Two or more of the following-paroxysmal sneezing, watery rhinorrhea, nasal itching, and nasal congestion-lasting continuously or cumulatively for at least 1 hour per day; ocular symptoms such as tearing, itching, and redness may also be present; (2) Persistent AR: Symptoms occur on ≥4 days per week and persist for ≥4 consecutive weeks;
• No use of probiotics, prebiotics, synbiotics, antihistamines, corticosteroids, or immunosuppressants within 1 month prior to screening;
• Willing and able to maintain usual physical activity levels and dietary patterns during the study;
• Able and willing to sign the informed consent form voluntarily.

You may not qualify if:

• Use of antibiotics, osmotic laxatives (e.g., magnesium sulfate, lactulose), anthraquinone-containing agents (e.g., rhubarb, aloe, senna), or gastrointestinal motility-promoting drugs (e.g., metoclopramide, domperidone, cisapride) within 1 month prior to screening;
• Diagnosed with non-allergic rhinitis (e.g., vasomotor rhinitis, infectious rhinitis, hormonal rhinitis, drug-induced rhinitis), or with nasal polyps, severe nasal septum deviation, cerebrospinal fluid rhinorrhea, or aspirin-exacerbated respiratory disease (AERD);
• Patients with uncontrolled allergic comorbidities, including sinusitis, otitis media, allergic asthma, or atopic dermatitis;
• History of serious gastrointestinal diseases (e.g., severe diarrhea, inflammatory bowel disease), or gastrointestinal endoscopy within the past month;
• Diagnosed with congenital genetic disorders, primary immunodeficiency diseases, severe systemic illnesses, or malignancies;
• Influenza vaccination within the past 6 months;
• Pregnant or lactating women, or women with plans to conceive during the study period.

Sponsors & Collaborators

• LanZhou University: lead

Study Sites (1)

School of Public Health, Lanzhou University

Lanzhou, Gansu, China

Location

MeSH Terms

Conditions

Respiratory Tract Infections

Condition Hierarchy (Ancestors)

Infections; Respiratory Tract Diseases

Central Study Contacts

Xiaoqin Li, Dr.Prof.

CONTACT

+86 15927366423; lixiaoqin@lzu.edu.cn

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor, School of Public Health, Lanzhou University

Study Record Dates

• First Submitted: July 4, 2025
• First Posted: July 25, 2025
• Study Start: July 25, 2025
• Primary Completion (Estimated): December 31, 2026
• Study Completion (Estimated): December 31, 2026
• Last Updated: July 25, 2025

Record last verified: 2025-07

Data Sharing

• IPD Sharing: Will not share

Locations

CN (1)