Actively Recruiting
A Randomized, Blinded Phase I/II Trial to Evaluate Safety, Tolerability, and Immune Response of Influenza Vaccine (Split Virion), Inactivated, Quadrivalent, ZFA02 Adjuvant
Led by Anhui Zhifei Longcom Biologic Pharmacy Co., Ltd. · Updated on 2026-05-05
620
Participants Needed
1
Research Sites
56 weeks
Total Duration
On this page
AI-Summary
What this Trial Is About
Researchers are evaluating the safety, tolerability, and immune response to different doses of an Influenza Vaccine (Split Virion), Inactivated, Quadrivalent, ZFA02 Adjuvant in this seamless Phase I/II clinical trial. The study aims to find the best dose for future trials by first increasing age and dose levels and then expanding the dose groups. It includes healthy adults starting from 18 years old and compares the new vaccine against a positive control vaccine, with a blinded and randomized design. The trial has two stages. In Phase I, participants aged 18 to 49 and 50 and above receive either low-dose or high-dose vaccines or placebo in four cohorts, with careful safety monitoring after vaccination. Phase II enrolls 500 subjects divided into two age groups (18-49 and 50+), randomly assigned to low-dose, high-dose, or positive control vaccine groups. The study ensures a proper mix of older adults, including those aged 60 and above. Each participant receives a single vaccine dose according to their assigned group. Participants will be monitored closely with safety checks including blood and urine tests four days after vaccination and follow-up for adverse events up to 12 months. Researchers will assess vaccine-related side effects, immune response by measuring antibody levels 30 days post-vaccination, and other safety markers. The study includes careful observation of any serious adverse events and autoimmune reactions. The total participation time varies but involves multiple visits and assessments to ensure comprehensive safety and immune response data collection.
CONDITIONS
Brief Title
Clinical Trials of Quadrivalent Influenza Vaccine
Who Can Participate
Eligibility Criteria
You may qualify if you...
- Be at least 18 years old and provide valid identification
- Understand the trial procedures and voluntarily agree to participate by signing consent
- Have an axillary temperature of 37.0°C or lower on enrollment day
- Agree to use effective contraception for 6 months if of childbearing age
You will not qualify if you...
- Have abnormal clinically significant lab results before vaccination (Phase I only)
- Had influenza within 6 months before enrollment
- Have autoimmune or immunodeficiency diseases
- History of severe allergies to vaccines, drugs, eggs, or vaccine components
- Received any influenza vaccine within 6 months before enrollment or plan to during trial
- Used investigational or unregistered products within 30 days before enrollment or plan to during trial
- Received live vaccines within 30 days or other vaccines within 14 days before enrollment
- Have acute illness or are in acute phase of chronic illness within 3 days before enrollment
- Used antipyretic, analgesic, or anti-allergic drugs within 3 days before enrollment
- Used immunoglobulin or blood products within 3 months before enrollment or plan to use during trial
- Long-term use of immunosuppressants or immunomodulatory drugs within 3 months before enrollment
- Absence or functional absence of spleen
- Have coagulation dysfunction or history of anticoagulant therapy
- History of epilepsy, encephalopathy, or malignant tumors
- Serious cardiovascular diseases, unstable hypertension, diabetes with serious complications, or other serious chronic diseases
- Respiratory diseases, severe liver or kidney diseases, or mental disorders
- Women who are pregnant, breastfeeding, or have positive pregnancy test
- Plan to move away or be unavailable during the study
- Other factors judged by researchers as unsuitable for participation
AI-Screening
AI-Powered Screening
Complete this quick 3-step screening to check your eligibility
Your Study Journey
Duration - 2 to 4 weeks
Participants are screened for eligibility to participate in the trial.
1 visit (in-person)
Duration - 1 day
Participants receive one dose of either low-dose or high-dose influenza vaccine, placebo, or positive control vaccine depending on their randomized group assignment.
1 vaccination visit (in-person)
Duration - Up to 12 months after vaccination
Participants are monitored for safety and immune response for up to 12 months after vaccination, including assessments at 4 days and 30 days post-vaccination.
Multiple visits including assessments on Day 4 and Day 30 post-vaccination
Trial Site Locations
Total: 1 location
1
Hebei Province Centers for Disease Control and Prevention
Shijiazhuang, Hebei, China
Actively Recruiting
Research Team
F
Fei Jin
How is the study designed?
Study Type
INTERVENTIONAL
Masking
TRIPLE
Allocation
RANDOMIZED
Model
PARALLEL
Primary Purpose
PREVENTION
Number of Arms
14
Similar Trials
Frequently Asked Questions
Have more questions? Get in touch with our team for quick support
Not the Right Trial for You?
Explore thousands of other clinical trials that might be a better match.
Sign up to get personalized trial recommendations delivered to your inbox.
Already have an account? Log in here