FDA Approves Pfizer’s ABRYSVO Vaccine for the Prevention of RSV

Pfizer’s ABRYSVO, a respiratory syncytial virus vaccine, has been approved by the U.S. Food and Drug Administration (FDA) for the prevention of lower respiratory tract disease (LRTD) and severe LRTD caused by RSV in infants from birth up to 6 months of age by active immunization of pregnant individuals at 32 through 36 weeks gestational age. 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 approval was based on the data from the pivotal Phase III clinical trial (NCT04424316) MATISSE (MATernal Immunization Study for Safety and Efficacy), a randomized, double-blinded, placebo-controlled study designed to evaluate the efficacy, safety and immunogenicity of the vaccine against LRTD and severe LRTD due to RSV in infants born to healthy individuals vaccinated during pregnancy.

“ABRYSVO’s approval as the first and only maternal immunization to help protect newborns immediately at birth through 6 months from RSV marks a significant milestone for the scientific community and for public health,” said Annaliesa Anderson, PhD, senior vice president and chief scientific officer of vaccine research and development at Pfizer. “We are incredibly grateful to the clinical trial participants and study investigator teams around the world, as well as our Pfizer colleagues, for their commitment to making this vaccine available. Today, a long-sought-after goal to deliver a maternal vaccine that will help protect infants 6 months of age or younger — when they are at greatest risk of possible serious consequences from RSV — has been achieved.”

In May, FDA approved ABRYSVO, for the prevention of LRTD caused by RSV in individuals 60 years and older. That decision was based on data from the pivotal Phase III clinical trial, RENOIR (RSV vaccine Efficacy study iNOlder adults Immunized against RSV disease), a global, randomized, double-blind, placebo-controlled study designed to assess the efficacy, immunogenicity and safety of a single dose of the vaccine in adults 60 years of age and older. RENOIR has enrolled approximately 37,000 participants, randomized to receive RSVpreF 120 μg or placebo in a 1:1 ratio. Results showed positive top-line results when co-administered with seasonal inactivated influenza vaccine in adults 65 years and older.

Pfizer has initiated two additional clinical trials evaluating ABRYSVO. One trial is being conducted in children at higher risk for RSV disease ages 2 year to less than 18 years. A second trial is evaluating adults ages 18 to 60 at higher risk for RSV due to underlying medical conditions such as asthma, diabetes and chronic obstructive pulmonary disease, and adults ages 18 and older who are immunocompromised and at high-risk for RSV. Pfizer also plans postmarketing studies and surveillance programs to further describe the safety of the vaccine.