FDA Approves GSK's RSV Vaccine for Adults Aged 18-49 at Increased Risk

The FDA approved an expanded indication for GSK’s respiratory syncytial virus (RSV) vaccine, adjuvanted (Arexvy; GSK), allowing its use in adults aged 18 to 49 years who are at increased risk for lower respiratory tract disease (LRTD) caused by RSV. The vaccine was previously authorized in the United States for adults 60 years and older and adults aged 50 to 59 years at increased risk for LRTD caused by RSV.¹

The approval marks a significant expansion of the vaccine's eligible population. In the US, an estimated 21 million adults younger than 50 years have at least 1 risk factor for severe RSV infection. The annual RSV burden among US adults aged 18 to 49 years amounts to roughly 17,000 hospitalizations, 277,000 emergency department admissions, and 1.97 million outpatient visits. Most hospitalizations in younger populations occur among those with chronic medical conditions—including chronic cardiopulmonary disease, kidney or renal disease, obesity, and diabetes—that place them at elevated risk for severe RSV disease.¹

“This age expansion can help address a significant medical need for adults in the US at higher risk of severe RSV disease due to certain underlying conditions and help ease pressure on the health care system,” Sanjay Gurunathan, head of vaccines and infectious diseases research and development at GSK, said in the news release. “We are proud of this latest step in our strategy to bring RSV prevention to broader adult populations.”¹

The FDA's decision was supported by data from a phase 3b, open-label immunogenicity trial (NCT06389487). The study enrolled 1458 participants across 52 locations in 6 countries, including 16 US sites. The results showed a noninferior immune response in adults aged 18 to 49 years at increased risk compared with adults 60 years and older. The trial's co–primary end points were RSV-A and RSV-B neutralization titers measured 1 month after vaccination.^1,2

Vaccine efficacy was established in an earlier phase 3 trial (NCT04886596). The safety profile was consistent with findings from the broader phase 3 program, with the most common adverse events being injection site pain, fatigue, myalgia, headache, and arthralgia within 4 days of vaccination.^1,3

According to the prescribing information, the RSV vaccine, adjuvanted, contains recombinant RSV glycoprotein F stabilized in the prefusion conformation (RSVPreF3) combined with GSK's proprietary AS01E adjuvant system. The vaccine is approved for the prevention of RSV-LRTD in individuals 60 years and older in 70 countries and in those aged 50 to 59 years at increased risk in more than 60 countries.^1,4

Pharmacists play a critical role in identifying patients aged 18 to 49 years with qualifying conditions—including chronic obstructive pulmonary disorder, asthma, congestive heart failure, diabetes, and chronic kidney disease—and counseling them on their new eligibility for RSV vaccination. As Advisory Committee on Immunization Practices guidance for this age group evolves, staying current on updated recommendations will be essential to supporting patient access to this expanded protection.

REFERENCES

1. GSK’s RSV vaccine, Arexvy, approved in US for expanded age indication in adults aged 18-49 years at increased risk. News release. GSK. March 13, 2026. Accessed March 13, 2026. https://www.gsk.com/en-gb/media/press-releases/gsk-s-rsv-vaccine-arexvy-approved-in-us-for-expanded-age-indication-in-adults-aged-18-49-years-at-increased-risk/

2. A study on the immune response and safety of vaccine against respiratory syncytial virus (RSV) given to adults 18 to 49 years of age at increased risk for respiratory syncytial virus disease, compared to older adults 60 years of age and above. ClinicalTrials.gov. Updated September 25, 2025. Accessed March 13, 2025. https://clinicaltrials.gov/study/NCT06389487

3. Efficacy study of GSK’s investigational respiratory syncytial virus (RSV) vaccine in adults aged 60 years and above. ClinicalTrials.gov. Updated July 31, 2025. Accessed March 13, 2026. https://clinicaltrials.gov/study/NCT04886596

4. Arexvy (respiratory syncytial virus vaccine, adjuvanted) for injectable suspension, for intramuscular use. Prescribing information. GSK; 2026. Accessed March 13, 2026. https://gskpro.com/content/dam/global/hcpportal/en_US/Prescribing_Information/Arexvy/pdf/AREXVY.PDF