RSV Vaccine Triggers Strong Immune Response in People Aged 60 and Older

A phase 3 randomized controlled trial has shown that the RSV vaccine “triggered strong immune responses among people aged 60 years and older during its first two seasons for use.” CIDRAP has the news.

For the RENOIR (RSV Vaccine Efficacy Study in Older Adults Immunized against RSV Disease) study, a research team “randomly assigned a subset of participants in the United States and Japan in a 1:1 ratio to receive one dose of Pfizer's bivalent (two-strain) RSV Prefusion F (RSVpreF) vaccine or a placebo. The respiratory syncytial virus (RSV) vaccine triggered strong immune responses among people aged 60 years and older during its first two seasons for use.”

The vaccine, which is sold under the brand name Abrysvo, “contains molecules called antigens designed to produce an immune response against RSV-A and RSV-B. It is approved for preventing RSV infection in adults aged 60 years and older, those aged 18 to 59 at increased risk for severe illness, and infants through maternal vaccination.”

In the RSVpreF group, “proportions of participants with immune responses were higher 1-month postvaccination…than at the preseason-2 visit” and “much higher than placebo.” RSV-A and -B GMFRs (geometric mean fold rise) in participants with selected chronic conditions were generally comparable to those of their otherwise healthy peers (range, 11.4 to 14.4). The vaccine also showed a favorable safety profile during both seasons, with 6.2% of RSVpreF and 6.1% of those in the placebo group reporting a serious adverse event.”