FDA Approval for an RSV Vaccine
Respiratory syncytial virus (RSV) is a highly contagious virus that infects the lungs and breathing passages of individuals of all ages. RSV typically starts to circulate in the fall, peaking in winter. In older adults, RSV commonly results in respiratory tract disease, impacting the lungs and potentially resulting in life-threatening bronchiolitis or pneumonia. According to the U.S. Centers for Disease Control and Prevention, RSV in the U.S. results annually in up to 120,000 hospitalizations and up to 10,000 deaths among adults aged 65 and older 1. A recent surge in cases accelerated research and funding into preventative and therapeutic options for RSV infection, with a major success being FDA approval for a vaccine.
On May 3rd, 2023, the U.S. Food and Drug Administration gave approval for the first RSV vaccine, Arexvy, manufactured by GlaxoSmithKline, for use in the U.S. 1. This was the first RSV vaccine to gain approval anywhere in the world 2. More recently, in late May 2023, the Food and Drug Administration also approved Pfizer’s RSV vaccine, ABRYSVO, based on the prefusion F protein developed by scientists of the National Institute of Allergy and Infectious Diseases (NIAID) 3. Meanwhile, additional vaccines are under development 4. Moderna is wrapping up its Phase 3 trial for an mRNA vaccine for RSV in older adults, aiming to submit results to the Food and Drug Administration in the next few months. Bavarian Nordic will also soon report data from a Phase 3 trial of its RSV vaccine for older adults in 2023 5.
The assessment of the safety and effectiveness of these vaccines is based on the Food and Drug Administration’s analysis of data from large-scale clinical studies. Most recently, ABRYSVO’s safety and efficacy was based on the data from the pivotal Phase 3 clinical trial named RENOIR (RSV vaccine Efficacy study iN Older adults Immunized against RSV disease) 6, a global, randomized, double-blind, placebo-controlled study aimed at assessing the efficacy, immunogenicity, and safety of a single dose of the RSV vaccine in adults aged 60 and older. Published results were clearly promising 7, with the vaccine preventing RSV-associated lower respiratory tract illness and RSV-associated acute respiratory illness in patients without incurrent any safety concerns.
This said however, one recipient of the Arexvy vaccine in the trial did develop the neurological condition Guillain-Barré syndrome 4. The Food and Drug Administration will therefore require GlaxoSmithKline to closely monitor the incidence of Guillain-Barré after the vaccine becomes widely deployed.
Both Arexvy and ABRYSVO have received approval as vaccine options for the prevention of lower respiratory tract disease caused by RSV infection in individuals aged 60 and over. However, young children are also adversely affected by RSV, with the Centers for Disease Control estimating that it results in up to 80,000 hospitalizations annually in the U.S. To protect infants, Pfizer aims to immunize pregnant women a few months before giving birth 4.
The recent Food and Drug Administration-approved RSV vaccines represent a significant public health achievement, resulting from decades of scientific discovery and research at the National Institutes of Health and private institutions. Further research into RSV vaccine options and treatment options will expand protection for vulnerable populations.
References
1. FDA Approves First Respiratory Syncytial Virus (RSV) Vaccine | FDA. Available at: https://www.fda.gov/news-events/press-announcements/fda-approves-first-respiratory-syncytial-virus-rsv-vaccine. (Accessed: 3rd June 2023)
2. Vidal Valero, M. ‘A good day’: FDA approves world’s first RSV vaccine. Nature 617, 234–235 (2023).
3. NIH Celebrates FDA Approval of RSV Vaccine for People 60 Years of Age and Older | NIH: National Institute of Allergy and Infectious Diseases. Available at: https://www.niaid.nih.gov/news-events/nih-celebrates-fda-approval-rsv-vaccine-people-60-years-age-and-older. (Accessed: 3rd June 2023)
4. FDA Approves RSV Vaccine for Adults 60 Years and Older | AAFP. Available at: https://www.aafp.org/pubs/afp/afp-community-blog/entry/fda-approves-rsv-vaccine-for-adults-60-years-and-older.html. (Accessed: 3rd June 2023)
5. FDA approves Pfizer’s RSV vaccine for older adults | CNN. Available at: https://www.cnn.com/2023/05/31/health/fda-pfizer-rsv-vaccine/index.html. (Accessed: 5th June 2023)
6. U.S. FDA Approves ABRYSVOTM, Pfizer’s Vaccine for the Prevention of Respiratory Syncytial Virus (RSV) in Older Adults | Pfizer. Available at: https://www.pfizer.com/news/press-release/press-release-detail/us-fda-approves-abrysvotm-pfizers-vaccine-prevention. (Accessed: 3rd June 2023)
7. Walsh, E. E. et al. Efficacy and Safety of a Bivalent RSV Prefusion F Vaccine in Older Adults. N. Engl. J. Med. (2023). DOI: 10.1056/NEJMoa2213836