Safety labelling changes have been made in the US and UK for the Respiratory Syncytial Virus (RSV) vaccines Abrysvo (Pfizer Inc.) and Arexvy (GlaxoSmithKline Biologicals). Both vaccines will now include a warning about the potential risk of Guillain-Barré syndrome (GBS) following administration.
Updated Safety Warnings:
- Abrysvo: Postmarketing data suggest an increased risk of GBS within 42 days of vaccination.
- Arexvy: Similarly, a postmarketing study indicates an increased risk of GBS within 42 days of vaccination.
GBS is a rare but serious autoimmune disorder in which the immune system attacks peripheral nerves, causing muscle weakness and, in severe cases, paralysis. While the overall risk remains low, awareness is crucial for clinicians assessing post-vaccination neurological symptoms.
About the Vaccines
Abrysvo (Pfizer)
- Approved (May 2023) for preventing lower respiratory tract disease (LRTD) caused by RSV in adults 60+ years.
- Subsequent approvals include use in:
- Adults 18–59 years at increased risk for LRTD.
- Pregnant individuals (32–36 weeks gestation) to protect infants up to 6 months old from severe RSV-related LRTD.
Arexvy (GSK)
- Approved (May 2023) for LRTD prevention in adults 60+ years.
- Later expanded to include individuals 50–59 years at higher risk of RSV-related LRTD.
Neurologists should be aware of this safety update when evaluating patients presenting with acute neurological symptoms post-vaccination. Clinicians are encouraged to report suspected adverse events in the US here and the UK here.
While the absolute risk remains small, ongoing monitoring and vigilance in post-vaccination neurological assessments are recommended.
