RSV DISEASE — RSV typically causes a mild upper respiratory tract infection in adults, but older adults and adults of any age with certain underlying health conditions have an increased risk of RSV-associated lower respiratory tract disease. RSV epidemics in the Northern Hemisphere typically occur between October and April, peaking in December or January.

CLINICAL STUDIES — A single dose of Arexvy has been shown to reduce the incidence of RSV-associated lower respiratory tract disease in adults ≥60 years old for up to 3 RSV seasons (median follow-up 30.6 months). FDA licensure for use in younger patients was based on the results of an immunogenicity trial that included 1029 adults 18-49 years old with chronic medical conditions (kidney or liver disease, diabetes, or cardiopulmonary, neuromuscular, or neurologic conditions), but not immunosuppression. The trial also enrolled a comparator group of adults ≥60 years old who received the vaccine. One month after vaccination with Arexvy, RSV-A and RSV-B neutralizing antibody responses in adults 18-49 years old were noninferior to those in adults ≥60 years old.2 In a previous immunogenicity trial, immune responses to the vaccine in adults 50-59 years old with or without chronic medical conditions were noninferior to those in adults ≥60 years old.3

ADVERSE EFFECTS — Adverse effects reported with Arexvy in the immunogenicity trial were similar in participants 18-49 years old and ≥60 years old but were reported at higher rates in the younger age group. The most common adverse effects reported in adults 18-49 years old within 4 days of receiving the vaccine were injection-site pain (76%), myalgia (60%), fatigue (60%), headache (44%), and arthralgia (28%). Guillain-Barré syndrome and atrial fibrillation have been reported rarely following vaccination with Arexvy; a causal relationship has not been established.4

RECOMMENDATIONS — The CDC Advisory Committee on Immunization Practices (ACIP) recommends one-time RSV vaccination for all adults ≥75 years old and for those 50-74 years old at increased risk for severe RSV disease (see Table 1).5 The ACIP has not yet issued a recommendation for RSV vaccination of adults <50 years old. The Infectious Diseases Society of America (IDSA) and the American Medical Association recommend RSV vaccination for all immunocompromised adults ≥18 years old.6,7

For optimal protection, the vaccine should be given before the onset of the RSV season. Administration of a RSV vaccine and other vaccines during the same visit is acceptable, but local or systemic reactogenicity could increase.

DOSAGE, ADMINISTRATION, AND COST — Arexvy is given as a single 0.5-mL IM injection. The wholesale acquisition cost (WAC) for one dose is $321.8