WEDNESDAY, May 3, 2023 (HealthDay News) -- The first vaccine for respiratory syncytial virus (RSV) has been approved by the U.S. Food and Drug Administration for use in seniors aged 60 years and older. Arexvy is expected to help prevent lower respiratory tract infections caused by RSV, the agency said Wednesday.
Now that the vaccine is approved, the U.S. Centers for Disease Control and Prevention will weigh later this summer whether all seniors should get the shot or just those considered at high risk for severe infection.
The FDA gave its approval based on a clinical trial in which approximately 12,500 participants 60 years of age and older from around the world randomly got an Arexvy vaccine, while 12,500 others received a placebo shot. Results from a single RSV season showed that the vaccine was 82.6 percent effective in preventing RSV-induced lower respiratory tract infections and just over 94 percent effective in reducing the risk for a severe infection. Participants will remain in the study through three RSV seasons to assess the duration of effectiveness, as well as the safety and effectiveness of repeat vaccination, the FDA said.
The most commonly reported side effects by individuals who received Arexvy were injection site pain, fatigue, muscle pain, headache, and joint stiffness or pain, the FDA said. Among all clinical trial participants, atrial fibrillation within 30 days of vaccination was reported in 10 participants who received Arexvy and four participants who received the placebo.
Two other clinical trials involving Arexvy showed some concerning side effects that have warranted further review. In one of the trials, participants received Arexvy along with an FDA-approved influenza vaccine. One person died after developing acute disseminated encephalomyelitis (ADEM), while a second became ill with ADEM. In the other study, one participant developed Guillain-Barré syndrome nine days after receiving Arexvy.
The FDA is requiring GlaxoSmithKline to conduct a postmarketing study to assess the signals of serious risks for Guillain-Barré syndrome and ADEM. The company also has committed to assess atrial fibrillation in the postmarketing study.
Approval of Arexvy was granted to GlaxoSmithKline Biologicals.