Respiratory Syncytial virus vaccine effective in older adults, finds NEJM study

A recent study published in The New England Journal of Medicine suggest that a single dose of the Respiratory syncytial virus prefusion F protein–based candidate vaccine (RSVPreF3 OA) is safe and effective in preventing RSV-related acute respiratory infection and lower respiratory tract disease, including severe cases, in older adults, regardless of RSV subtype and the presence of underlying coexisting conditions.

Respiratory syncytial virus is a major cause of acute respiratory infections and lower respiratory tract diseases in older adults, with no licensed vaccine available for prevention. In a phase 3, international, placebo-controlled trial, Alberto Papi and colleagues investigated the efficacy and safety of a single dose of an AS01E-adjuvanted RSVPreF3 OA in adults aged 60 years or older before the RSV season.

A total of 24,966 participants were randomized to receive either the vaccine (12,467 participants) or a placebo (12,499). Over a median follow-up of 6.7 months, the vaccine efficacy against RT-PCR–confirmed RSV-related lower respiratory tract disease was 82.6%, with 7 cases (1.0 per 1000 participant-years) in the vaccine group and 40 cases (5.8 per 1000 participant-years) in the placebo group.

The vaccine efficacy was 94.1% against severe RSV-related lower respiratory tract disease and 71.7% against RSV-related acute respiratory infection. Moreover, the vaccine efficacy was similar against both RSV A and B subtypes.

High vaccine efficacy was observed across different age groups and in participants with underlying coexisting conditions. The vaccine was more reactive than the placebo, but most adverse events were transient and mild-to-moderate in severity. The incidences of serious adverse events and potential immune-mediated diseases were similar in both groups.

These findings are significant because older adults are at a high risk of RSV-related complications, and the availability of an effective vaccine can have a significant impact on reducing the morbidity and mortality associated with RSV infection.

Source:

Papi, A., Ison, M. G., Langley, J. M., Lee, D.-G., Leroux-Roels, I., Martinon-Torres, F., Schwarz, T. F., van Zyl-Smit, R. N., Campora, L., Dezutter, N., de Schrevel, N., Kostanyan, L., & Hulstrøm, V. (2023). Respiratory Syncytial Virus Prefusion F Protein Vaccine in Older Adults. In New England Journal of Medicine (Vol. 388, Issue 7, pp. 595–608). Massachusetts Medical Society. https://doi.org/10.1056/nejmoa2209604