The updated indication for the respiratory syncytial virus vaccine is for adults aged 50 to 59 with underlying conditions who are at an increased risk of contracting the virus.
The FDA has granted Priority Review to an application to extend the indication of the adjuvanted respiratory syncytial virus (RSV) vaccine (Arexvy; GlaxoSmithKline) to include adults aged 50 to 59 who are at an increased risk of virus onset. Although the vaccine is currently indicated for adults aged 60 and older with lower respiratory tract disease (LRTD), this updated approval would make this vaccine the first available to this patient population.1
Adults can be at a higher risk of contracting RSV due to comorbidities, immune compromised status, or age. In addition, RSV can aggravate prior conditions including asthma, chronic obstructive pulmonary disease, diabetes, and chronic heart failure, which can lead to pneumonia, hospitalization, or death in some cases.
The adjuvanted vaccine consists of recombinant glycoprotein F stabilized in the prefusion conformation (RSVPreF3) and is combined with a proprietary AS01E adjuvant. In addition to being approved in the US, the vaccine is also approved for the prevention of RSV-LRTD in individuals 60 years and older in Europe, Japan, UK, Canada, and other countries.1
The application follows results from a placebo-controlled, observer-blind, multi-country, randomized phase 3 trial (NCT05590403) that evaluated the immune response and safety of this RSV vaccine in adults aged 50 to 59 and included those who were at an increased risk of RSV-LRTD due to underlying medical conditions. The trial enrolled a total of 570 patients aged 50 to 59 who had pre-defined stable chronic diseases that could result in an increased risk of RSV. In addition, the immune responses in a broader group of individuals (n = 570) of the same age without pre-defined conditions were also evaluated. The vaccine group consisted of both healthy adults and adults at an increased risk of RSV, who all received a dose of the RSV vaccine intramuscularly at day 1. Similarly, the placebo group also had both healthy adults and those who were a higher risk of contracting RSV.
Primary end points of the study include group geometric mean titer ratio and seroresponse rate in both groups. Secondary end points include safety and tolerability profiles (eg, adverse events, potential immune mediated diseases) at the study’s end (12 months) as well as the frequency of RSVPreF3-specific CD8+ T cells that are assessed at 1 month, 6 months, and 12 months after the administration of intervention.
In addition, a priority review voucher to reduce the FDA review period of a supplemental Biologics License Application by 4 months was also submitted. According to the study authors, the results of the trial will be presented at upcoming conferences. The results were also submitted for peer-reviewed publications.1
1. GlaxoSmithKline. GSK’s RSV vaccine, Arexvy, accepted under Priority Review in US for the prevention of RSV disease in adults aged 50-59 at increased risk. News release. February 6, 2024. Accessed February 12, 2024. https://www.gsk.com/en-gb/media/press-releases/arexvy-accepted-under-priority-review-in-us-for-the-prevention-of-rsv-disease-in-adults-aged-50-59-at-increased-risk/
2. A Study on the Immune Response and Safety of a Vaccine Against Respiratory Syncytial Virus Given to Adults 50-59 Years of Age, Including Adults at Increased Risk of Respiratory Syncytial Virus Lower Respiratory Tract Disease, Compared to Older Adults 60 Years of Age and Above. ClinicalTrials.gov identifier: NCT05590403. Updated July 28, 2023. Accessed February 12, 2024. https://classic.clinicaltrials.gov/ct2/show/NCT05590403