## GSK’s Arexvy Shows Promise for Expanding RSV Vaccine Protection to Younger Adults
GlaxoSmithKline (GSK) has announced encouraging preliminary data for its Arexvy (Respiratory Syncytial Virus Vaccine, Adjuvanted) in adults aged 18-49 who are at increased risk for lower respiratory tract disease (LRTD). This news could potentially expand the reach of the vaccine to a larger population and address a critical need for RSV protection in a demographic that currently lacks approved vaccines.
The data highlights Arexvy’s potential to help safeguard a broader group of adults at risk from the potentially serious consequences of RSV. In the U.S. alone, the number of adults aged 18-49 with at least one risk factor for RSV disease could exceed 21 million. This signifies a significant population that stands to benefit from access to an effective vaccine.
Currently, Arexvy is approved for adults aged 60 and older and those aged 50-59 at increased risk for RSV-LRTD. However, there are currently no RSV vaccines recommended for adults younger than 60 years of age who are at increased risk for RSV disease. This gap in vaccination coverage leaves a substantial portion of the population vulnerable to the virus.
The positive results stem from two clinical trials. In the phase 3b trial, a single dose of Arexvy elicited robust immune responses in adults aged 18-49 at increased risk for RSV-LRTD due to certain underlying medical conditions. This immune response was non-inferior to that observed in adults 60 and older, meeting the trial’s co-primary endpoints. This finding underscores the potential efficacy of Arexvy in younger adults at risk.
Further evidence comes from the phase 2b trial, which examined the vaccine’s effectiveness in immunocompromised adults aged 18 and older due to kidney or lung transplants. A single dose of Arexvy demonstrated a robust immune response in this population, while a second dose elicited responses comparable to those observed in healthy adults aged 50 and older who received one dose. These consistent immune responses across subgroups for both RSV-A and RSV-B subtypes suggest the vaccine’s broad potential in protecting individuals with diverse immune profiles.
This development comes as GSK and Pfizer face declining sales for their respective RSV vaccines due to the narrow age recommendations. The recent approval of Pfizer’s Abrysvo for adults aged 18-59 at high risk and the CDC’s recommendation for routine RSV vaccinations in all adults aged 75 and above have shifted the landscape. The positive data for Arexvy in younger adults could revitalize GSK’s position in the RSV vaccine market and address the unmet need for broader protection against this potentially serious respiratory virus. The next step will be to see how these findings translate into regulatory approval and expanded accessibility of Arexvy for a wider range of adults at risk for RSV disease.