PfizerPfizer Inc. (NYSE: PFE) announced that the U.S. Food and Drug Administration's (FDA) Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted that available data is adequate to support the safety and effectiveness of its respiratory syncytial virus (RSV) bivalent vaccine candidate PF-06928316 or RSVpreF. The Committee voted 7 to 4 on safety and 7 to 4 on effectiveness. The vaccine candidate is currently under FDA review for the prevention of acute respiratory disease and lower respiratory tract disease caused by RSV in adults 60 years of age and older.

"In older adults, RSV can result in serious illness, hospitalization, or even death, so there is a significant need to protect this at-risk population," said Annaliesa Anderson, Ph.D., Senior Vice President and Chief Scientific Officer, Vaccine Research and Development, Pfizer. "We are encouraged by the outcome of today's VRBPAC meeting as it is a testament to the strength of our science and dedication to bringing this important vaccine candidate to the market. We look forward to working with the FDA as it completes the review of our application."

The 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) announced with top-line results in August 2022 and presented at IDWeek 2022. Pfizer intends to publish these results in a peer-reviewed scientific journal.

The role of the VRBPAC is to provide recommendations to the FDA; however, these recommendations are not binding. The FDA’s decision on whether or not to approve RSVpreF for the prevention of acute respiratory disease and lower respiratory tract disease caused by RSV in individuals 60 years of age and older is expected by the Prescription Drug User Fee Act (PDUFA) goal date in May 2023.

Burden of RSV

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 alone, among older adults, RSV infections account for approximately 60,000-160,000 hospitalizations and 6,000-13,000 deaths each year.(5,6,7,8,9,10,11,12,13) Among children younger than five years old in the U.S., RSV infections account for approximately 2.1 million outpatient visits and 58,000-80,000 hospitalizations occur each year.(8,14,15)

RSV is a disease for which there are currently no targeted prophylactic, therapeutic, or vaccine options for older adults and the medical community is limited to offering only supportive care for adults with the illness.

About RSVpreF

Pfizer is currently the only company pursuing regulatory applications for an RSV investigational vaccine candidate for both an indication to help protect older adults, as well as a maternal indication to help protect infants through maternal immunization. Regarding the maternal indication, earlier this month Pfizer announced that the FDA had granted priority review to a biologics license application for RSVpreF for the prevention of lower respiratory tract and severe lower respiratory tract disease caused by RSV in infants from birth up to six months of age by active immunization of pregnant individuals. A Prescription Drug User Fee Act (PDUFA) action date in August 2023 was set.

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.

About Pfizer: Breakthroughs That Change Patients' Lives

At Pfizer, we apply science and our global resources to bring therapies to people that extend and significantly improve their lives. We strive to set the standard for quality, safety and value in the discovery, development and manufacture of health care products, including innovative medicines and vaccines. Every day, Pfizer colleagues work across developed and emerging markets to advance wellness, prevention, treatments and cures that challenge the most feared diseases of our time. Consistent with our responsibility as one of the world's premier innovative biopharmaceutical companies, we collaborate with health care providers, governments and local communities to support and expand access to reliable, affordable health care around the world. For more than 170 years, we have worked to make a difference for all who rely on us.

1. Centers for Disease Control and Prevention. Respiratory Syncytial Virus Infection (RSV). https://www.cdc.gov/rsv/index.html. Updated December 18, 2020. Accessed November 18, 2022.
2. Centers for Disease Control and Prevention. RSV Transmission. https://www.cdc.gov/rsv/about/transmission.html. Updated December 18, 2020. Accessed November 18, 2022.
3. Centers for Disease Control and Prevention. Respiratory Syncytial Virus Infection (RSV) - Older Adults are at High Risk for Severe RSV Infection Fact Sheet. https://www.cdc.gov/rsv/factsheet-older-adults.pdf. Accessed November 18, 2022.
4. Centers for Disease Control and Prevention. RSV in Infants and Young Children. https://www.cdc.gov/rsv/high-risk/infants-young-children.html. Updated December 18, 2020. Accessed November 18, 2022.
5. Centers for Disease Control and Prevention. RSV Surveillance & Research. https://www.cdc.gov/rsv/research/index.html. Accessed February 21, 2023.
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10. Centers for Disease Control and Prevention. October 2022 ACIP Meeting Slides. ACIP Adult RSV Work Group Considerations. Available at: www.cdc.gov/vaccines/acip/meetings/downloads/slides-2022-10-19-20/04-RSV-Adults-Melgar-508.pdf. Accessed February 21, 2023.
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12. Matias G, Taylor R, Haguinet F, et al. Estimates of Mortality Attributable to Influenza and RSV in the United States during 1997–2009 by Influenza Type or Subtype, Age, Cause of Death, and Risk Status. Influenza Other Respir Viruses. 2014; 8(5):507-15.
13. Hansen CL, Chaves SS, Demont C, Viboud C. Mortality Associated With Influenza and Respiratory Syncytial Virus in the US, 1999-2018.JAMA Network Open. 2022 Feb 1;5(2):e220527.
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