FDA Approves Arexvy and Abrysvo: Primary Regulatory Details on RSV Prevention in Adults 60+

The FDA approved Arexvy on May 3, 2023 as the first vaccine to prevent lower respiratory tract disease caused by RSV in adults 60 years and older. [1] Trial data linked the vaccine to 82.6 percent efficacy against RSV-associated lower respiratory tract disease over one season. [1] CDC reports associate RSV with 60,000 to 160,000 hospitalizations and 6,000 to 10,000 deaths each year among adults 65 and older. [3] The CDC later issued guidance on vaccine use in this group. [2]

What this means

The approval marked the first licensure of any RSV vaccine in the United States. The phase 3 trial enrolled thousands of adults and compared Arexvy to placebo. It measured protection against confirmed RSV illness and met its statistical criteria for efficacy. [1] Safety findings fell within acceptable parameters for the studied population.

The CDC examined the trial results together with data on disease occurrence. Its report supports a single dose for adults 60 and older through shared clinical decision-making that accounts for personal risk factors. [2] This guidance does not set a universal requirement.

RSV infection occurs seasonally and links to higher rates of severe illness in older adults. Those with heart or lung conditions face elevated risks. [3] The factsheet outlines how age and certain chronic conditions connect to increased hospitalization rates.

Key takeaways

• FDA approved Arexvy on May 3, 2023, for prevention of RSV lower respiratory tract disease in adults 60 years and older. [1]
• The pivotal trial showed 82.6 percent efficacy against RSV-LRTD over one season, with a 95 percent confidence interval of 57.9 to 94.1. [1]
• CDC guidance issued later recommends that adults 60 and older may receive one dose of an RSV vaccine based on shared clinical decision-making. [2]
• RSV is associated with 60,000–160,000 hospitalizations and 6,000–10,000 deaths annually in U.S. adults 65 and older. [3]
• Prior to 2023, no RSV vaccine had been licensed for use in any age group. [1]

Limitations

Trial follow-up was limited to a single RSV season, so duration of immunity beyond one year remains uncertain. Efficacy and safety data in adults older than 80, those with severe frailty, or immunocompromised status are limited. Real-world effectiveness, impact on hospitalizations, and signals of rare adverse events such as Guillain-Barré require ongoing pharmacovigilance. Cost-effectiveness, insurance coverage, and uptake data were outside the scope of the FDA regulatory decision. These points indicate where post-approval data collection may add clarity.