FDA to decide on Pfizer vaccine for older adults by May 2023

The Food and Drug Administration is expected to decide by spring whether to approve Pfizer’s vaccine to prevent respiratory syncytial virus, or RSV, in adults ages 60 and older.

Pfizer, in a statement Wednesday, said the FDA has accepted its RSV vaccine candidate for review under an expedited process that reduces the approval process by four months. The FDA is expected to make a final decision on whether to approve the vaccine by May 2023.

RSV is a common respiratory virus that causes cold like symptoms in most people, but it can result in severe illness in infants and older adults. Between 60,000 and 120,000 older adults are hospitalized with RSV every year and 6,000 to 10,000 older adults die from the virus.

There is no vaccine for RSV.

Pfizer’s vaccine candidate was about 86% effective in preventing severe lower respiratory tract illness, defined as three or more symptoms. The vaccine was about 67% effective at preventing milder lower respiratory tract illness, defined as two or more symptoms.

“With no RSV vaccines currently available, older adults remain at-risk for RSV disease and potential severe outcomes, including serious respiratory symptoms, hospitalization, and in some cases, even death,” said Annaliesa Anderson, Pfizer’s head of vaccine research and development.

The U.S. is facing an unusually tough RSV season this year. RSV transmission was very low during the Covid pandemic due to masking and social distancing measures. Many people did not get infected as a consequence, so population immunity is lower right now.

Since October, seniors have been hospitalized with RSV at 10 times the rate observed in 2018 to 2019, the last full season before the onset of the Covid pandemic.

Pfizer is also developing a maternal vaccine to protect newborns who are too young for vaccination.