“Breaking Boundaries: FDA Greenlights Pfizer’s Revolutionary Maternal RSV Vaccine, Shielding Infants”
In a remarkable stride forward, the FDA has granted approval to Pfizer’s groundbreaking Abrysvo vaccine against respiratory syncytial virus (RSV) for use in pregnant women, aiming to safeguard infants from RSV-associated lower respiratory tract disease.
Abrysvo stands as a unadjuvanted bivalent RSV prefusion F vaccine, uniquely designed to combat both RSV A and B strains. Originally endorsed in June 2023 for older adults aged 60 and above, Abrysvo’s new approval extends its reach to pregnant women at 32 through 36 weeks of gestation, nurturing immunity in their newborns.
Pfizer’s Chief Scientific Officer, Annaliesa Anderson, hailed Abrysvo as the “first and only maternal immunization to help protect newborns immediately at birth through six months.”
The FDA’s decision finds solid footing in the Phase III MATISSE trial results. At its interim analysis, Abrysvo displayed remarkable efficacy, boasting 81.8% prevention of severe RSV-associated lower respiratory tract disease 90 days after birth, a figure that slightly eased to 69.4% at 180 days.
This achievement earned Abrysvo the resounding endorsement of the FDA’s Vaccines and Related Biological Products Advisory Committee. In May 2023, the committee demonstrated unanimous support for Pfizer’s efficacy data, voting 10–4 on safety, with attention to the non-statistically significant uptick in premature births linked to Abrysvo.
Pfizer’s journey with Abrysvo continues as the company pioneers its development. Two clinical trials are underway, assessing the vaccine’s impact on high-risk children aged two through 17 years and adults aged 18 through 60 years with underlying conditions.
A trailblazer alongside Pfizer is Sanofi’s and AstraZeneca’s Beyfortus (nirsevimab), an FDA-approved monoclonal antibody for pediatric RSV immunization. This innovative approach targets the RSV virus’s attachment to host cells, a milestone achievement for infants entering their first RSV season and at-risk children up to 24 months old.
Pfizer’s triumph in the RSV realm finds companionship in GSK, which clinched the FDA’s inaugural vaccine approval in the field for older adults aged 60 years and above. Meanwhile, Moderna advances its own mRNA-based RSV shot, embarking on a journey that could reshape the landscape of RSV prevention. In July 2023, the company announced the initiation of its Biologics License Application rolling submission with the FDA, signaling an exciting horizon of possibilities.