Pfizer Inc. (NYSE: PFE) announced today that the U.S. Food and Drug Administration’s (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted that the available data support the efficacy and safety of its unadjuvanted bivalent respiratory syncytial virus (RSV) prefusion F vaccine candidate RSVpreF or PF-06928316. The Committee voted 14 to 0 on effectiveness and 10 to 4 on safety. The vaccine candidate is currently under FDA review for the prevention of medically attended lower respiratory tract disease (MA-LRTD) and severe MA-LRTD caused by RSV in infants from birth up to six months of age by active immunization of pregnant individuals.
“We are encouraged by the outcome of today’s VRBPAC meeting as it is a critical step forward in the scientific community’s long-sought-after goal to help prevent RSV disease in infants during their most vulnerable first six months of life,” said Annaliesa Anderson, Ph.D., Senior Vice President and Chief Scientific Officer, Vaccine Research and Development, Pfizer. “If approved, our RSV vaccine candidate has the potential to be the first maternal immunization vaccine to help protect infants at first breath through their first six months of life from this potentially serious infection.”
The VRBPAC based its recommendation on the scientific evidence shared by Pfizer, including primary analysis results from the pivotal Phase 3 clinical trial (NCT04424316) MATISSE (MATernal Immunization Study for Safety and Efficacy) announced in November 2022. These results were also recently published in The New England Journal of Medicine.
The role of the VRBPAC is to provide recommendations to the FDA; however, these recommendations are not binding. The FDA’s decision on the potential approval of RSVpreF for the prevention of MA-LRTD and severe MA-LRTD caused by RSV in infants by active immunization of pregnant individuals is expected by the Prescription Drug User Fee Act (PDUFA) goal date in August 2023.
Burden of RSV in Infants
RSV is a contagious virus and a common cause of respiratory illness.1 The virus can affect the lungs and breathing passages of an infected individual and can potentially cause severe illness in young infants, older adults, and individuals with certain chronic medical conditions.2,3,4
In the United States, approximately 500,000 to 600,000 cases of MA-LRTD due to RSV occur annually in infants less than 12 months of age.5 Worldwide, there are an estimated 6.6 million cases of RSV annually in infants less than six months of age, with approximately 45,000 dying each year from complications associated with the infection, and the vast majority in developing countries.6,7,8
Pfizer is currently the only company pursuing regulatory applications for an RSV investigational vaccine candidate for both an older adult indication, as well as a maternal indication to help protect infants through maternal immunization.
In December 2022, Pfizer announced that the FDA had granted priority review to a biologics license application for RSVpreF for the prevention of RSV disease in older adults with a decision on whether or not to approve RSVpreF expected by thePDUFA goal date later this month. This was followed by the February 2023 vote by VRBPAC in support of the safety and effectiveness of RSVpreF in adults 60 years of age and older. The FDA’s VRBPAC based its recommendation on the scientific evidence shared by Pfizer, including interim data from the pivotal Phase 3 clinical trial (NCT05035212) RENOIR (RSV vaccine Efficacy study iN Older adults Immunized against RSV disease). Top-line results for RENOIR were previously announced by Pfizer in August 2022 and presented at IDWeek and the CDC’s Advisory Committee on Immunization Practices (ACIP) in October 2022, as well as recently published in The New England Journal of Medicine.