British pharmaceutical company GlaxoSmithKline PLC announced on Friday that the U.S. Food and Drug Administration (FDA) has expanded the approved age range for its respiratory syncytial virus (RSV) vaccine Arexvy. The vaccine is now authorized for adults aged 18 to 49 who are at increased risk of developing lower respiratory tract disease due to the virus.

The vaccine had previously been approved in the United States for use in adults aged 60 and above, as well as for high-risk adults aged 50 to 59, to prevent RSV-related illness.

Respiratory syncytial virus (RSV) is a common respiratory virus that causes seasonal infections such as influenza and is a leading cause of pneumonia and mortality in infants and the elderly.

GlaxoSmithKline stated that an estimated 21 million adults under the age of 50 in the United States have at least one risk factor for severe RSV infection.

GlaxoSmithKline's Arexvy vaccine will compete for market share in the 18-49 age group with Moderna's mRESVIA and Pfizer's Abrysvo.

In December of last year, an expert panel of the European Medicines Agency (EMA) also supported the use of Arexvy in all adults aged 18 and above, paving the way for broader application of the vaccine.