Pfizer’s RSV vaccine Abrysvo shown to maintain strong efficacy in older adults

RSV infections account for up to 160,000 hospitalisations among older adults each year in the US. Pfizer has shared positive top-line results from a late-stage trial of its respiratory syncytial virus (RSV) vaccine in adults aged 60 years and older.

RSV is a common contagious virus characterised by several mild, cold-like symptoms. There are two major subgroups of the virus, RSV A and RSV B, both of which cause disease and can co-circulate or alternate predominance from season to season.

Although most people recover within a week or two, RSV can cause severe illness in older adults, young infants and individuals with certain chronic medical conditions.

Among older adults, RSV infections account for approximately 60,000 to 160,000 hospitalisations and 6,000 to 13,000 deaths each year in the US.

Pfizer’s Abrysvo is already approved in major markets, including the US and EU, to protect older adults against RSV as well as infants through maternal immunisation.

Results from the ongoing RENOIR trial have shown that the vaccine maintained consistently high protective efficacy for both RSV A and RSV B disease through two seasons after a single dose.

Abrysvo efficacy was 77.8% against RSV lower respiratory tract disease (LRTD) with three or more symptoms in a second full RSV season in adults 60 years and older.

Consistent vaccine efficacy was demonstrated for both RSV A and RSV B after season two, with vaccine efficacy against each subtype of at least 80% for LRTD with three or more symptoms.

March 6, 2024