The US Food & Drug Administration is currently reviewing two candidates for a vaccine to prevent respiratory syncytial virus in older adults.

One of these, a vaccine developed by Pfizer, is detailed in a new study in the New England Journal of Medicine,

Respiratory syncytial virus (RSV) in older adults has become an increasing concern. There are an estimated 60,000 to 120,000 hospitalizations and 6,000 to 10,000 deaths in adults 65 years or older each year from RSV infection, according to the Centers for Disease Control (CDC).

Severity of RSV disease can increase with age and comorbidities, such as chronic obstructive pulmonary disease, congestive heart failure, and asthma. Along with COVID and the flu, RSV contributed to the “tripledemic” that has been placing significant strain on the nation’s health care system over the last several months.

Previous research has shown that RSV infection does not give a person lasting immunity afterward, and re-infection can happen throughout the lifespan. There is currently no FDA-approved RSV vaccine, but after nearly five decades of vaccine-development efforts, researchers are on the cusp of approval.

Edward Walsh, professor of medicine at the University of Rochester Medical Center, has a long history with Pfizer, working on multiple viral pathogens over the years. This long-standing relationship led to URMC being named a lead site with Walsh as national lead investigator for Pfizer’s phase 3 clinical trial of the RSV vaccine for older adults.

In late February, Pfizer presented efficacy and safety data from that clinical trial, available in the New England Journal of Medicine article, to the FDA and the Vaccines and Related Biological Products Advisory Committee (VRBPAC). Walsh was also a lead investigator on the preliminary trials that preceded the phase 3 study.

The promising results show that Pfizer’s vaccine has an efficacy of 66.7% to prevent general illness, an efficacy of 85.7% to prevent lower respiratory tract infection with three or more symptoms, and an efficacy of 62.1% to prevent acute respiratory infection. After presenting full data, the VRBPAC voted in favor of recommending this vaccine to the FDA for approval.

Read the full article about RSV vaccine by Kelly Webster at Futurity.