RSV Vaccine Shows Potential Protection for Middle Aged Adults

GSK plc today announced positive preliminary results from its phase III clinical trial evaluating the immune response and safety of the AREXVY™ respiratory syncytial virus (RSV) vaccine in adults aged 50 to 59, including those at increased risk of RSV lower respiratory tract disease (LRTD) due to certain underlying medical conditions.

In this study, the vaccine elicited an immune response in adults aged 50 to 59 at increased risk for RSV disease due to select underlying medical conditions that were non-inferior to that observed in adults aged 60 and above, meeting the trial's primary co-endpoint.

Vaccine efficacy has previously been demonstrated in adults aged 60 and above.

The co-primary endpoint was also met for the broader group of adults aged 50 to 59 also enrolled in the trial. Safety and reactogenicity data were consistent with results from the initial phase III program.

The most common local adverse event was pain, and the most common systematic adverse events were fatigue and headache, most of which were transient and mild in intensity.

These results will be presented at the US Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices meeting on October 25, 2023.

AREXVY is currently approved in the United States, Europe, Japan, and several other countries for active immunization for the prevention of RSV-LRTD in adults 60 years of age and older. 

AREXVY recombinant, AS01E adjuvanted, single dose, RSV vaccine contains a recombinant subunit pre-fusion RSV glycoprotein antigen (RSVPreF3) combined with GSK's proprietary ASO1 adjuvant. 

Tony Wood, Chief Scientific Officer, GSK, said in a press release on October 25, 2023, "This trial reinforces our confidence in our RSV vaccine's ability to help protect adults aged 50 to 59 at increased risk for RSV-LRTD."

"We will submit these data for regulatory review as quickly as possible with the goal of offering adults in this age group the option of a vaccine for the first time."

There is a substantial burden of RSV-associated illness for adults at increased risk for RSV disease due to advanced age, immunocompromised status, or underlying medical conditions, such as chronic obstructive pulmonary disease, asthma, and chronic heart failure. RSV can exacerbate these conditions and lead to pneumonia, hospitalization, or death.

The final results from this trial will be presented at an upcoming medical conference and submitted for peer-reviewed publication. The data will also be submitted to the US Food and Drug Administration and other regulators to support potential label expansions.