NEW YORK– Pfizer Inc. (NYSE:PFE) today announced that the U.S. Food and Drug Administration (FDA) has accepted for review a Biologics License Application (BLA) for its respiratory syncytial virus (RSV) vaccine candidate PF-06928316 or RSVpreF for the prevention of medically attended lower respiratory tract illness (MA-LRTI) and severe MA-LRTI caused by RSV in infants from birth up to six months of age by active immunization of pregnant individuals. This decision follows the FDA’s Breakthrough Therapy Designation for RSVpreF in March 2022. The FDA has accepted the BLA for priority review and has set a Prescription Drug User Fee Act (PDUFA) action date of August 2023.
“If approved, RSVpreF would help protect infants at their first breath from the devastating effects of this infectious disease, which though well-known, has been particularly evident throughout this RSV season,” said Annaliesa Anderson, Ph.D., Senior Vice President and Chief Scientific Officer, Vaccine Research & Development, Pfizer. “We look forward to progressing the review of Pfizer’s RSV maternal vaccine candidate with the FDA and other regulatory authorities, given its significant potential to positively contribute to global health in the prevention of RSV in infants.”
In addition, the European Medicines Agency (EMA) has accepted Pfizer’s marketing authorization application (MAA) under accelerated assessment for its RSV vaccine candidate for both older adults and maternal immunization to help protect infants. A decision is expected in the second half of 2023.
The maternal immunization regulatory submission is supported by the positive top-line results from MATISSE (MATernal Immunization Study for Safety and Efficacy), a Phase 3 clinical trial evaluating the efficacy, safety, and immunogenicity of RSVpreF against MA-LRTI and severe MA-LRTI in infants born to healthy women vaccinated during pregnancy. These data will be presented on February 23 to the U.S. Centers for Disease Control and Prevention’s (CDC) Advisory Committee on Immunization Practices (ACIP) and, separately, during the ReSViNET Foundation’s 2023 Global Conference on Novel RSV Preventive and Therapeutic Interventions.During the ACIP meeting on February 22-23, the company also will present positive Phase 3 results supporting the regulatory filings of Pfizer’s pentavalent meningococcal vaccine (MenABCWY) candidate, as well as Pfizer’s 20-valent pneumococcal conjugate vaccine (20vPnC) candidate for pediatric use.
In December 2022, Pfizer announced that the FDA had accepted for review a BLA for its MenABCWY candidate for the prevention of meningococcal disease caused by the most common serogroups in individuals 10 through 25 years of age. The PDUFA goal date for a decision by the FDA on the MenABCWY application is in October 2023. If approved and recommended, MenABCWY could help simplify the meningococcal vaccination schedule and provide the broadest serogroup coverage of any meningococcal vaccine. Top-line results from a randomized, active-controlled, and observer-blinded Phase 3 trial of Pfizer’s pentavalent meningococcal vaccine candidate (NCT04440163) were previously announced in September 2022.
Similarly, in January 2023, Pfizer announced that the FDA had granted priority review to a supplemental BLA for its 20vPnC candidate for the prevention of invasive pneumococcal disease (IPD) caused by the 20 Streptococcus pneumoniae (pneumococcus) serotypes contained in the vaccine in infants and children 6 weeks through 17 years of age, and for the prevention of otitis media caused by seven of the 20 Streptococcus pneumoniae serotypes contained in the vaccine. The PDUFA goal date for the FDA’s decision on the 20vPnC application is in April 2023. If approved, 20vPnC would have the potential to cover more of the clinically significant remaining burden of infant pneumococcal disease than any other available pneumococcal conjugate vaccine. In August 2022 Pfizer announced top-line results from its pivotal U.S. Phase 3 study (NCT04382326), which support the FDA application.
RSV is a contagious virus and a common cause of respiratory illness. 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.
Among children younger than five years old in the U.S., RSV infections account for approximately 2.1 million outpatient visits and 58,000 hospitalizations each year. Virtually all children get an RSV infection by the time they are 2 years old, and RSV is a leading cause of hospitalization in children <1 year of age.8 Worldwide, RSV results in the death of approximately 102,000 children annually, with about half of those in infants less than six months old and the vast majority in developing countries.
RSV bronchiolitis is the leading cause of infant hospitalization due to viral respiratory illness, characterized by respiratory distress that can result in death. There is no specific treatment for RSV, only supportive care measures like oxygen and fluids. Currently, there is no vaccine to help prevent RSV in the U.S., leaving most infants without protection. The only available preventive agent is recommended for use among the highest-risk infants in limited settings as a monthly injection with five doses administered during the RSV season.
Among adults 65 years and older, RSV infections account for approximately 60,000–160,000 hospitalizations and 6,000–10,000 deaths each year in the U.S. alone. There are currently no targeted prophylactic, therapeutic, or vaccine options for RSV in older adults, and treatment is limited to offering supportive care for adults with the illness.Pfizer’s investigational RSV vaccine candidate builds on foundational basic science discoveries including those made at the National Institutes of Health (NIH), which detailed the crystal structure of prefusion F, a key form of the viral fusion protein (F) that RSV uses to enter human cells. The NIH research showed that antibodies specific to the prefusion form were highly effective at blocking virus infection, suggesting a prefusion F-based vaccine may confer optimal protection against RSV. After this important discovery, Pfizer tested numerous versions of a stabilized prefusion F protein and identified a candidate that elicited a strong anti-viral immune response in pre-clinical evaluations. The bivalent vaccine candidate is composed of equal amounts of recombinant RSV prefusion F from subgroups A and B.
Pfizer is currently the only company with a maternal RSV vaccine candidate in late-stage development to help protect against RSV. 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.
