Pfizer says its RSV vaccine is highly effective in older adults.
In a phase 3 clinical trial, the company said its vaccine was 85.7% effective in preventing severe illness in adults 60 years and older.
The vaccine, called RSVpreF, was 66.u% effective in preventing a milder version of the illness, Pfizer said.
According to the Centers for Disease Control, an estimated 177,000 older adults are hospitalized with RSV every year and 14,000 of them die.
There is currently no approved vaccine to treat the virus.
“Scientists and researchers have worked to develop RSV vaccines with little success for over half a century. These findings are an important step in our effort to help protect against RSV disease, and we look forward to working with the FDA and other regulatory agencies to make this vaccine candidate available to help address the substantial burden of RSV disease in older adults," said Annaliesa Anderson, senior vice president and chief scientific officer for Pfizer.
Pfizer's data is preliminary. However, it plans to submit it for peer review in a scientific journal.