FDA Greenlights Pfizer's RSV Vaccine: Moms Can Now Protect Babies Before Birth

Monday, the FDA approved Pfizer Inc's PFE Abrysvo (Respiratory Syncytial Virus Vaccine), the company's bivalent RSV prefusion F (RSVpreF) vaccine, to prevent the infection in infants from birth up to six months of age by active immunization of pregnant individuals at 32 through 36 weeks gestational age.

First and only U.S. approval of a maternal vaccine to help protect infants at birth through six months of life from lower respiratory tract disease (LRTD) and severe LRTD due to RSV.

The FDA approved Abrysvo in May for use in adults over the age of 60.

 Abrysvo is unadjuvanted and composed of two preF proteins selected to optimize protection against RSV A and B strains and was observed to be safe and effective.

The FDA's decision is based on the pivotal Phase 3 MATISSE trial data in more than 7,000 pregnant individuals, including their infants, a total greater than 14,000 trial participants.

RSV is a contagious virus and a common cause of respiratory illness worldwide. 

The virus can affect an infected individual's lungs and breathing passages, potentially causing severe illness or death. In the U.S., approximately 500,000-600,000 infants experience LRTD due to RSV each year, a leading cause of hospitalization in children less than one year of age. 

The FDA in mid-July approved an RSV monoclonal antibody from Sanofi SA SNY and AstraZeneca Plc AZN that is directly administered to infants.

GSK Plc GSK sued Pfizer in Delaware court, alleging that Pfizer's Abrysvo violates GSK's four patent rights in its RSV shot Arexvy.

Price Action: PFE shares are up 0.27% at $37.11 during the premarket session on the last check Tuesday.