Regulatory review of benefits and risks of preventing infant RSV disease through maternal immunization

Area of Science:

• Immunology
• Vaccinology
• Maternal-Fetal Medicine

Background:

• Respiratory syncytial virus (RSV) is a significant cause of lower respiratory tract disease (LRTD) in infants.
• Existing prevention strategies for infant RSV infection have limitations.
• Maternal immunization is an emerging strategy to protect neonates.

Purpose of the Study:

• To summarize the FDA approval of Abrysvo for maternal immunization.
• To outline the recommended gestational age for Abrysvo administration.
• To discuss the balance between vaccine benefits and potential risks.

Main Methods:

• Review of FDA approval documentation for Abrysvo.
• Analysis of clinical trial data regarding vaccine efficacy and safety in pregnant individuals and infants.
• Consideration of pragmatic approaches to optimize vaccine use.

Main Results:

• Abrysvo received FDA approval in August 2023 for active immunization.
• The vaccine is indicated for pregnant individuals between 32-36 weeks gestational age.
• Prevention of LRTD caused by RSV in infants from birth to 6 months of age is the primary outcome.

Conclusions:

• Abrysvo represents a new tool for preventing infant RSV-LRTD through maternal vaccination.
• A pragmatic approach to the timing of Abrysvo administration is recommended.
• The vaccine's benefit-risk profile supports its use in pregnant individuals to protect infants.