The application, supported by positive results of a phase III trial showing immune response and an acceptable tolerability profile in this population, was accepted by the US Food and Drug Administration (FDA) under priority review. Adults aged 50 and above with underlying medical conditions were identified to be at an increased risk for RSV disease. GSK became the first company to file for regulatory approval to extend RSV vaccination to adults aged 50-59 at an increased risk. The FDA set a Prescription Drug User Fee Act action date of 7 June 2024.
GSK plc (LSE/NYSE: GSK) announced today that the US FDA had accepted under priority review an application to extend the indication of GSK’s adjuvanted respiratory syncytial virus (RSV) vaccine to adults aged 50-59 who are at increased risk for RSV disease. If approved, GSK’s RSV vaccine would be the first vaccine available to help protect this population. Arexvy is currently approved in the US in adults aged 60 and over for the prevention of lower respiratory tract disease (LRTD) caused by RSV.
The application was supported by positive results from a phase III trial [NCT05590403] evaluating the immune response and safety of GSK’s RSV vaccine in adults aged 50-59, including those at increased risk for RSV-LRTD due to underlying medical conditions. GSK utilized a Priority Review Voucher to reduce the US FDA review period of a supplemental Biologics License Application (sBLA) by four months. The Prescription Drug User Fee Act date, the FDA action date for their regulatory decision, was 7 June 2024.
The burden of RSV disease in adults is likely to have been underestimated due to a lack of awareness, standardized testing, and under-detection in surveillance studies. People with underlying medical conditions, such as chronic obstructive pulmonary disease (COPD), asthma, chronic heart failure, and diabetes, were identified to be at an increased risk for RSV disease. RSV can exacerbate these conditions and lead to pneumonia, hospitalization, or death.
About GSK’s RSV Vaccine Respiratory syncytial virus vaccine, adjuvanted, contains recombinant glycoprotein F stabilized in the prefusion conformation (RSVPreF3), combined with GSK’s proprietary AS01E adjuvant.
The FDA has approved GSK’s RSV vaccine for the prevention of lower respiratory tract disease (LRTD) caused by respiratory syncytial virus (RSV) in individuals 60 years of age and older. The vaccine’s use should be in accordance with official recommendations. As with any vaccine, a protective immune response may not be elicited in all vaccines.
The vaccine has also been approved for the prevention of RSV-LRTD in individuals 60 years of age and older in Europe, Japan, UK, Canada, and several other countries. Regulatory reviews in multiple countries are ongoing. The proposed trade name remains subject to regulatory approval in other markets.
The GSK proprietary AS01 adjuvant system contains STIMULON QS-21 adjuvant licensed from Antigenics Inc, a wholly-owned subsidiary of Agenus Inc. STIMULON is a trademark of SaponiQx Inc., a subsidiary of Agenus.
About the NCT05590403 trial NCT05590403 is a phase III, placebo-controlled, observer-blind, randomized, multi-country immunogenicity trial to evaluate the non-inferiority of the immune response and evaluate safety in participants aged 50 to 59 at increased risk of RSV-LRTD compared to older adults aged 60 years and above after a single dose of GSK’s RSV vaccine.
The study assessed the immune response in participants aged 50 to 59 with pre-defined stable chronic diseases leading to an increased risk of RSV disease (n=570). Immune responses in a broader group of participants aged 50-59 years without these pre-defined chronic diseases (n=570) were also evaluated compared to adults aged 60 and older. The trial’s primary endpoints were RSV-A and RSV-B neutralization titers of both groups of 50 to 59-year-olds at one month after the vaccine administration compared to adults aged 60 and older. There were also safety and immunogenicity secondary and tertiary endpoints.
Results from this trial will be presented at upcoming medical conferences and submitted for peer-reviewed publication. The data are being submitted to other regulators to support potential label expansions.
About RSV in adults RSV is a common contagious virus affecting the lungs and breathing passages. Adults can be at increased risk for RSV disease due to comorbidities, immune compromised status, or advanced age. RSV can exacerbate conditions, including COPD, asthma, and chronic heart failure and can lead to severe outcomes, such as pneumonia, hospitalization, and death. Each year, approximately 177,000 adults 65 years and older are hospitalized in the US due to RSV; an estimated 14,000 cases result in death.
