FDA Accepts for Priority Review BLA for RSV Vaccine

If approved the vaccine, RSVpreF, would be available for people 60 years of age and older. The Prescription Drug User Fee Act goal date for a decision is in May 2023.

The FDA has accepted for priority review a biologics license application (BLA) for Pfizer’s respiratory syncytial virus (RSV) vaccine, PF-06928316 or RSVpreF, in people 60 years of age and older. The Prescription Drug User Fee Act (PDUFA) goal date for a decision is in May 2023.

RSV is a contagious virus that can cause serious respiratory illness, affecting the lungs and breathing passages. It can be potentially life-threatening for older adults and adults with certain medical conditions. Each year it is estimated that 336,000 older adults are hospitalized globally due to RSV. In the United States, RSV infections in older adults account for about 177,000 hospitalizations and 14,000 deaths each year.

Pfizer’s bivalent vaccine candidate is composed of two preF proteins selected to optimize protection against RSV A and B strains. The vaccine builds on 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 that RSV uses to enter human cells.

“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,” Annaliesa Anderson, Ph.D., senior vice president and chief scientific officer of vaccine research & development at Pfizer, said in a press release.

The regulatory submission is supported by results of the phase 3 clinical trial RENOIR, which enrolled about 37,000 participants. In August 2022, Pfizer announced positive top-line results of an interim efficacy analysis. A data monitoring committee assessed protection against RSV-associated lower respiratory tract illness with two or more symptoms at 66.7%. Among patients with more severe disease, defined by three or more symptoms, the vaccine efficacy was 85.7%. The committee also indicated the vaccine was well-tolerated, with no safety concerns.

Additionally, in March 2022, the FDA had issued a breakthrough therapy designation for the prevention of RSV-associated lower respiratory tract disease in infants from birth up to six months of age by active immunization of pregnant women. The FDA designation was primarily based on the results of the phase 2b proof-of-concept study, which assessed the safety and immunogenicity of RSVpreF in healthy pregnant women who were vaccinated between 28- and 36-weeks gestation. A phase 3 study in this population is ongoing.