Clinical Trials of Quadrivalent Influenza Vaccine

This clinical trial adopts a seamless design of phase I/II, conducted in two stages: phase I and phase II. Phase I is the age/dose ramp up stage, and phase II is the dose expansion stage.The purpose of this clinical trial is to evaluate the safety and tolerability of different doses of Influenza Vaccine (Split Virion), Inactivated, Quadrivalent, ZFA02 Adjuvant，explore the immunogenicity of the vaccine, and determine the appropriate dose for later clinical trials of this product.

NCT Number	NCT06824519
Lead Sponsor	Anhui Zhifei Longcom Biologic Pharmacy Co., Ltd.
Conditions	Influenza, Human
Enrollment	620 participants
Start Date	2025-05-08
Primary Completion	2025-08-05 (estimated)
Study Completion	2026-09 (estimated)
Updated on ClinicalTrials.gov	2026-05-05