Anvisa Expands Bronchiolitis Vaccine Eligibility to Adults Over 18

The Brazilian Health Regulatory Agency, Anvisa, has approved the expansion of the Arexvy vaccine’s eligibility to include adults aged 18 and older. The vaccine, developed by GlaxoSmithKline (GSK), was previously approved for individuals aged 60 and older.

The expanded authorization allows the vaccine to be used for the prevention of lower respiratory tract disease caused by the respiratory syncytial virus (RSV) in a broader adult population.

Understanding RSV and Lower Respiratory Tract Disease

Respiratory syncytial virus is a common cause of bronchiolitis in children and can lead to severe lower respiratory tract disease (LRTD) in adults. While often appearing as a common cold, the virus can progress to more serious infections in vulnerable populations.

In the United States, the annual burden of RSV among adults aged 18 to 49 includes approximately 1.97 million outpatient visits, 277,000 emergency department admissions, and 17,000 hospitalizations.

The majority of these hospitalizations in younger adults occur in individuals with chronic medical conditions that increase their risk of severe disease, such as diabetes or chronic cardiopulmonary and renal diseases.

High-Risk Populations

Certain underlying health conditions significantly increase the risk of severe RSV illness. According to guidance from the Centers for Disease Control and Prevention (CDC) and data from GSK, these conditions include:

• Chronic cardiovascular disease, including coronary artery disease, heart failure, or congenital heart disease, though isolated hypertension is excluded.
• Chronic lung or respiratory diseases such as asthma, emphysema, chronic obstructive pulmonary disease (COPD), cystic fibrosis, or interstitial lung disease.
• End-stage renal disease or a dependence on renal replacement therapy, including hemodialysis.
• Diabetes mellitus when complicated by neuropathy, retinopathy, chronic kidney disease, other end-organ damage, or when the patient requires treatment with insulin or sodium-glucose cotransporter-2 (SGLT2) inhibitors.
• Neurologic or neuromuscular conditions that cause respiratory muscle weakness or impaired airway clearance.
• Obesity.

Global Regulatory Context

The decision by Anvisa follows similar regulatory movements in the United States. On March 13, 2026, the U.S. Food and Drug Administration (FDA) expanded the approved age indication for Arexvy to include adults aged 18 to 49 who are at increased risk for lower respiratory tract disease caused by RSV.

At the time of the FDA expansion, it was estimated that 21 million adults under the age of 50 in the United States had at least one risk factor for severe RSV infection.

This age expansion can help address a significant medical need for adults in the United States at higher risk of severe RSV disease due to certain underlying conditions, and help ease pressure on the healthcare system.

Sanjay Gurunathan, GSK Head of Vaccines and Infectious Diseases Research and Development

In the U.S., the FDA has licensed three RSV vaccines for adults aged 50 and older: GSK’s Arexvy, Pfizer’s Abrysvo, and Moderna’s mResvia.

Clinical Guidance and Administration

Guidance issued by the CDC on February 24, 2026, recommends a single dose of an RSV vaccine for all adults aged 75 and older, as well as adults aged 50 to 74 who are at an increased risk of severe illness.

The CDC states there is no preference among the available vaccines for adults 50 and older. While eligible adults may receive the vaccine at any time, the agency notes that the optimal time for vaccination is during the late summer or early fall, before RSV typically begins to spread within the community.

The RSV vaccine is not currently an annual vaccine. Individuals who have already received one dose have completed their vaccination series and are not advised to receive another dose at this time.

Regulatory documentation specifies that the Arexvy vaccine is not intended for use in pregnant individuals.