Pfizer on Thursday said a single dose of its new respiratory syncytial virus (RSV) vaccine Abrysvo maintained its ability to protect against the illness through a second year of respiratory disease season.
The company said in a press release that the vaccine's efficacy against RSV-associated lower respiratory tract disease with three or more symptoms was 77.8 per cent through season two, compared with efficacy of 88.9 per cent after the first RSV season, which led to the shot's US approval.
The data is from a late-stage trial of more than 37,000 participants being conducted in both the Northern and Southern hemispheres.
Cumulative efficacy over both seasons after around 16.4 months of disease surveillance was 81.5 per cent, Pfizer said.
The data is similar to the efficacy of GSK's rival RSV shot Arexvy over two seasons, which was released in June.
Both companies launched their RSV vaccines in the US last year. Pfizer chief executive Albert Bourla has called his company's launch a disappointment, after taking only around 35 per cent market share in the first season.
Pfizer said no new adverse events cropped up through the second RSV season beyond those reported in the clinical trial during the first season.
The company plans to submit the new data to regulatory authorities and publish these findings in a scientific journal.
(Reuters)
