1 Mar 2023 • A single dose of GSK's AS01E-adjuvanted respiratory syncytial virus (RSV) prefusion F protein-based candidate vaccine (RSVPreF3 OA) prevents RSV-related acute respiratory infection and lower respiratory tract disease in adults aged 60 years and older, according to a study published in New England Journal of Medicine.

The placebo-controlled, phase 3 trial involving adults aged 60 years or older who received a single dose of RSVPreF3 OA or placebo before the RSV season. A total of 24,966 participants were randomly assigned to one dose of vaccine (12,467 participants) or placebo (12,499 participants).

What were the findings?

• GSK's vaccine was 82.6% effective in preventing lower respiratory tract disease in people over 60, and 94.1% effective in preventing severe disease. (Pfizer's was 66.7% effective in preventing RSV-related lower respiratory tract illness with over two symptoms, and 85.7% effective against those with more than three)
• GSK's Vaccine efficacy was similar against the RSV A and B subtypes
• GSK's Vaccine efficacy was high in various age groups and especially among those with coexisting conditions. Most adverse events reported were transient, with mild-to-moderate severity, although the vaccine was more reactogenic than placebo

Both Pfizer and GSK’s respiratory syncytial virus (RSV) vaccines had instances of Guillain-Barré syndrome in clinical trials. And yet the FDA is only recommending that one of them conduct a new post-marketing study to assess the risk. Just Pfizer—which is seeking approval for RSVpreF, to be known as Abrysvo if approved—has been asked to submit a plan for a follow-up trial.

FDA advisory panel to give it's verdict this week. Stay tuned!

Source: MPR | Read full story