Pfizer’s respiratory syncytial virus (RSV) vaccine has been approved by the US Food and Drug Administration (FDA) to protect infants through the active immunisation of pregnant individuals.
The FDA’s decision allows Abrysvo to be given to those who are 32 to 36 weeks into their pregnancy to prevent lower respiratory tract disease (LRTD) and severe LRTD in infants from birth until they are six months old.
RSV is a common contagious virus characterised by several mild, cold-like symptoms. Although most people recover within a week or two, the virus can cause severe illness in young infants, older adults and individuals with certain chronic medical conditions.
Each year in the US, around 500,000 to 600,000 infants experience RSV-caused LRTD and an estimated 58,000 to 80,000 children below the age of five years are hospitalised due to RSV infection.
Annaliesa Anderson, senior vice president and chief scientific officer, vaccine research and development at Pfizer, said: “Abrysvo’s approval as the first and only maternal immunisation to help protect newborns immediately at birth through six months from RSV marks a significant milestone for the scientific community and for public health.”
The FDA’s decision was supported by positive results from the phase 3 MATISSE trial, in which the vaccine demonstrated 81.8% efficacy in preventing severe medically attended lower respiratory tract illness in infants in the first 90 days after birth, and 69.4% efficacy within 180 days.
Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, said: “RSV is a common cause of illness in children, and infants are among those at highest risk for severe disease, which can lead to hospitalisation.
“This approval provides an option for healthcare providers and pregnant individuals to protect infants from this potentially life-threatening disease.”
Abrysvo was also approved by the FDA in May for use in adults aged 60 years and older. The authorisation came less than a month after the US regulator approved GSK’s RSV vaccine, Arexvy, for use in the same patient population.
In July, AstraZeneca and Sanofi received US approval for their long-acting antibody therapy, Beyfortus (nirsevimab), to prevent LRTD in newborns and infants born during or entering their first RSV season.