RSV Vaccine Guillain-Barré Syndrome Side Effects To Be Added to Warning Labels for Abrysvo and Arexvy

Federal health officials are calling on two major drug manufacturers to add warning labels to the respiratory syncytial virus (RSV) vaccines Abrysvo and Arexvy, after several patients developed a rare nerve condition.

The U.S. Food and Drug Administration (FDA) issued an Abrysvo and Arexvy safety communication on January 7, requiring Pfizer and GlaxoSmithKline, the respective manufacturers, to warn the medical community and recipients that side effects of the RSV vaccines may cause Guillain-Barré syndrome (GBS).

Respiratory Syncytial Virus is a prevalent respiratory virus that usually causes mild, cold-like symptoms. However, it is the leading cause of pneumonia in young children and older adults, where it can pose a serious, life-threatening risk. Recently, RSV cases have surged nationwide, prompting health officials to strongly advocate for the use of RSV vaccines to protect vulnerable populations.

Guillain-Barré syndrome is a rare neurological disorder in which the immune system attacks the body’s nerve cells, causing muscle weakness and, in some cases, paralysis. While many individuals recover fully, some may experience permanent nerve damage.

Treatment often involves specialized blood therapies, physical therapy and rehabilitation to manage symptoms and aid recovery. In severe cases, the condition can be life-threatening, requiring urgent medical attention.

According to the FDA, post-market clinical trials conducted by Pfizer and GlaxoSmithKline determined that some patients developed Guillain-Barré syndrome within 42 days of being vaccinated with Abrysvo and Arexvy.

The agency indicates that during the Arexvy clinical trial, one patient developed Guillain-Barré after receiving the vaccine. In the Abrysvo clinical trial, one patient developed the disease and another developed a variant.

Last year, the U.S. Centers for Disease Control and Prevention (CDC) postponed allowing Arexvy to be used in the 50-59 age group, because of its risks and the link to Guillain-Barré.

RSV Vaccine Label Warnings

The new FDA advisory calls for a Guillain-Barré warning to be added to the prescribing information for both RSV vaccines. The revised warnings will include the following language:

• Abrysvo — The results of a postmarking observational study suggest an increased risk of Guillain-Barré syndrome during the 42 days following vaccination with Abrysvo.
• Arexvy — The results of a postmarking observational study suggest an increased risk of Guillain-Barré syndrome during the 42 days following vaccination with Arexvy.

The FDA recommends that patients who have received the RSV vaccine and suspect they are experiencing side effects should report the symptoms to the Vaccine Adverse Event Reporting System (VAERS). VAERS is an online platform co-managed by the FDA to help detect possible safety problems in vaccines approved in the U.S.