A Phase 3 Randomized, Observer-Blind, Controlled Study to Evaluate the Immunogenicity, Reactogenicity and Safety of an mRNA-based Seasonal Influenza Vaccine, in Adults 18-64 Years of Age
This clinical trial will study an investigational seasonal influenza vaccine in adults 18 to 64 years of age. The vaccine is based on messenger ribonucleic acid, also called mRNA. The main goals of the study are to learn how well the vaccine helps the body make an immune response against influenza and what medical problems participants may have after vaccination. Researchers will also compare immune responses in adults 18 to 64 years of age from this study, with immune responses in adults 65 years of age and older from another study. Participants will receive 1 injection into the upper arm muscle and will be followed for about 6 months.
• Participants who, in the opinion of the investigator, can and will comply with the requirements of the protocol (e.g., completion of the eDiary, return for follow-up visits, attendance to study contacts, and ability to access and utilize a phone or other electronic communications) independently or with the assistance of a caregiver.
• A male or female participant between and including 18 to 64 years of age at the time of study intervention administration
• Participants of childbearing potential may be enrolled, if the participant:
‣ has practiced adequate contraception for at least 30 days prior to study intervention administration, and
⁃ has a negative urine pregnancy test within 24 hours prior to study intervention administration, and
⁃ has agreed to continue adequate contraception for at least 8 weeks after study intervention administration.