New real-world evidence presented by GSK shows its RSV vaccine, Arexvy, was associated with substantial reductions in RSV-related hospitalizations and serious cardiovascular and respiratory complications among older adults.
GSK has unveiled new real-world effectiveness data for Arexvy, its adjuvanted respiratory syncytial virus (RSV) vaccine, at RSVVW’26, the ninth conference of the Respiratory Syncytial Virus Foundation (ReSViNET), held in Rome, Italy. The company is presenting 19 abstracts at the congress and supporting an additional 3, underscoring its expanding role in RSV research and prevention.
Arexvy is approved for the prevention of RSV-related lower respiratory tract disease in adults 60 years or older as well as adults aged 50 to 59 years who are at increased risk. RSV remains a significant cause of hospitalization among older adults, particularly during winter respiratory virus seasons, placing strain on both patients and health care systems.
The centerpiece of GSK’s presentation is a large US retrospective cohort study involving more than 2.5 million adults 60 years or older. The analysis compared 520,440 vaccinated individuals with more than 2.08 million unvaccinated individuals who were matched at a 1:4 ratio. Participants in the vaccinated group received Arexvy between August 2023 and May 2024 and were followed for a median of 5.6 months.
Results showed that vaccination with Arexvy was associated with 75.6% vaccine effectiveness (VE) against RSV-related hospitalization, with a 95% CI of 69.8% to 80.2%. These findings suggest meaningful protection against severe RSV outcomes during the first season following immunization.
Exploratory analyses from the same study pointed to potential benefits beyond hospitalization prevention. Arexvy was associated with a 63.1% reduction in major adverse cardiovascular events, including heart attack and stroke, occurring during RSV-related hospitalizations. Additional analyses showed VE of 74.4% against severe chronic obstructive pulmonary disease (COPD) exacerbations and 61.6% against severe asthma flare-ups among vaccinated adults.
Complementing the US data, a separate nationwide cohort study in Denmark evaluated adults 60 years or older with COPD. In that analysis, Arexvy was associated with 100% effectiveness in preventing RSV-related hospitalization, with no hospitalizations observed among vaccinated individuals during the study period.
Real-world US data show Arexvy was associated with a 75.6% reduction in RSV-related hospitalizations among adults 60 years or older.
Exploratory findings suggest potential reductions in cardiovascular events and severe COPD and asthma flare-ups during RSV-related hospitalizations.
Consistent results from US and Danish studies strengthen evidence supporting RSV vaccination in older and high-risk adults.
Although results from observational studies cannot establish causality, experts say the findings add to a growing body of evidence suggesting RSV vaccination may help reduce severe respiratory and cardiovascular complications linked to RSV infection.
“In the real-world data being presented at RSVVW’26, it is observed that RSV vaccination could help reduce the risk of certain serious RSV-related outcomes, potentially including major adverse cardiovascular events such as heart attack and stroke as well as severe flare-ups of COPD and asthma,” Deepak L. Bhatt, MD, MPH, MBA, director of Mount Sinai Fuster Heart Hospital and the Dr. Valentin Fuster Professor of Cardiovascular Medicine at the Icahn School of Medicine at Mount Sinai in New York, New York, said in a statement. “These new data are a significant step in our understanding of how to help prevent such RSV-related health outcomes. I look forward to more data investigating this association further.”
