Pfizer’s respiratory syncytial virus (RSV) maternal vaccine candidate has been recommended for approval by a US Food and Drug Administration (FDA) panel of experts.
The Vaccines and Related Biological Products advisory committee (VRBPAC) voted unanimously that the available data supported the efficacy of RSVpreF in helping to protect against the complications of RSV in infants from birth to six months of age.
The committee also voted ten to four that the data supported the safety of the candidate.
RSV is a contagious virus characterised by several mild, cold-like symptoms. Although most people recover within a week or two, the virus can potentially cause severe illness in young infants, older adults and individuals with certain chronic medical conditions.
An estimated 58,000 to 80,000 children under the age of five are hospitalised each year in the US due to RSV infection.
Pfizer’s single-dose vaccine is administered in the late second to third trimester of pregnancy. The antibodies triggered by the vaccine are then passed to the foetus to protect against RSV.
The committee’s decision was supported by top line results from the phase 3 MATISSE trial, in which the vaccine demonstrated 81.8% efficacy in preventing severe medically attended lower respiratory tract illness in infants in the first 90 days of life.
Pre-planned reviews conducted at regular intervals throughout the trial also indicated that the vaccine was well tolerated, with no safety concerns for both the vaccinated individual and their newborns.
The FDA will now consider the panel’s advice as it makes a decision regarding the potential approval of the vaccine, with a decision expected in August.
Annaliesa Anderson, senior vice president and chief scientific officer, vaccine research and development at Pfizer, said: “We are encouraged by the outcome of [the] VRBPAC meeting as it is a critical step forward in the scientific community’s long-sought-after goal to help prevent RSV disease in infants during their most vulnerable first six months of life.
“If approved, our RSV vaccine candidate has the potential to be the first maternal immunisation vaccine to help protect infants at first breath through their first six months of life from this potentially serious infection.”
Pfizer is also currently pursuing regulatory applications for an RSV investigational vaccine candidate for older adults, which recently received backing from VRBPAC.