The FDA Approves Pfizer’s Vaccine for Older Adults to Treat and Prevent RSV
Overview
The Food and Drug Administration has approved a vaccine made by Pfizer that protects adults aged 60 and older from respiratory syncytial virus (RSV). RSV is a common pathogen that kills and hospitalizes thousands of seniors every year.
Pfizer anticipates having supply available in the third quarter of this year ahead of the RSV season. The Centers for Disease Control and Prevention’s committee of independent advisors will meet to make recommendations on the use of the vaccine.
The approval of Pfizer’s vaccine comes a few weeks after the FDA cleared a similar shot targeting RSV that is made by GSK.
The two FDA authorizations are significant milestones for public health, following decades of failed efforts to develop vaccines for the virus.
RSV causes mild symptoms similar to a cold in most people but poses a higher risk of severe illness among older adults. The virus kills 6,000 to 10,000 older adults and hospitalizes 60,000 to 160,000 of them annually, according to the federal Centers for Disease Control and Prevention.
RSV also circulates at the same time as Covid and flu. The combined burden of the three viruses put substantial pressure on the healthcare system in late 2020. The two new RSV vaccines from Pfizer and GSK may help ease some of that pressure this fall.
Pfizer’s shot is administered as a single 120-microgram dose. The vaccine was about 67% effective against lower respiratory tract illness with at least two signs or symptoms and about 86% effective against this illness with three signs or symptoms, according to clinical trial results.
The FDA’s advisors backed Pfizer’s vaccine in February, but several panel members voiced safety concerns about the shot. Two participants in Pfizer’s clinical trial developed Guillain-Barre syndrome after receiving the vaccine, a rare neurological disorder ranging from brief weakness to paralysis.
The FDA views the two Guillain-Barre cases as possibly linked to the vaccine and has asked Pfizer to conduct a post-approval safety study to monitor the disorder. Pfizer also developed a vaccine to protect newborns from RSV, which the FDA’s advisors backed in a meeting earlier this month. The FDA is expected to make a final decision on that vaccine in August.
The significance of the approval
The approval of Pfizer’s vaccine marks a major milestone in the long quest to develop RSV vaccines. For years, public health officials have identified RSV as a significant public health threat, particularly to older adults. The virus is responsible for a significant number of hospitalizations and deaths every year, particularly among elderly populations. With the approval of Pfizer’s vaccine, health experts hope to reduce the burden of RSV on the healthcare system and protect vulnerable populations from severe illness.
The effectiveness of the vaccine
The clinical trial results suggest that Pfizer’s vaccine is about 67% effective against lower respiratory tract illness with at least two signs or symptoms and about 86% effective against this illness with three signs or symptoms. While the efficacy rates are not as high as some other vaccines, such as the Pfizer-BioNTech Covid-19 vaccine, health experts believe that the vaccine will still be effective in preventing severe illness and death from RSV.
The safety concerns raised by the FDA
Two participants in Pfizer’s clinical trial developed Guillain-Barre syndrome after receiving the vaccine, which is a rare neurological disorder that can range from brief weakness to paralysis. The FDA views the two Guillain-Barre cases as possibly linked to the vaccine and has asked Pfizer to conduct a post-approval safety study to monitor for the disorder. While the safety concerns are significant, health experts agree that the benefits of the vaccine outweigh the risks and believe that the vaccine is safe and effective for most people.