Moderna mRNA Flu Vaccine Broadens B Cell and Antibody Responses

Overview

• A Nature Immunology paper published June 15 reports that Moderna’s investigational mRNA vaccine, mRNA-1010, elicited broader B cell responses and antibodies that bound more diverse flu strains than a standard inactivated shot.
• The researchers followed 75 adults ages 20 to 50 and found that mRNA recipients produced higher levels of flu-specific antibodies and more memory B cells than recipients of the licensed Fluarix vaccine.
• In a lymph-node subset, five of 13 mRNA recipients showed flu-specific germinal center activity that persisted for 26 weeks while persistent responses were not seen in 15 traditional-vaccine recipients.
• Moderna previously reported a separate Phase 3 result showing a 26.6% greater reduction in illness versus a standard vaccine in older adults, and the company’s mRNA candidate is currently under review by the U.S. FDA.
• The mRNA platform could allow faster updates and manufacturing of seasonal flu vaccines and the new immune data suggest a path to broader, more durable protection, but larger and more diverse trials are needed before changing policy or guidance.