Respiratory Syncytial Virus (RSV) vaccines from GSK and Pfizer will carry warnings for an increased risk of Guillain-Barré syndrome (GBS), the U.S. Food Drug Administration (FDA) said.
“To inform the public and healthcare providers that FDA has required and approved safety labeling changes to the Prescribing Information for Abrysvo (Respiratory Syncytial Virus Vaccine) manufactured by Pfizer Inc. and Arexvy (Respiratory Syncytial Virus Vaccine, Adjuvanted) manufactured by GlaxoSmithKline Biologicals. Respiratory Syncytial Virus (RSV) vaccine,” the FDA said.
The warning was added after the FDA conducted a postmarketing observational study that assessed the risk of developing GBS following vaccination. The FDA concluded there was a risk for GBS upon evaluating Medicare claims data. “GBS diagnoses in claims data were confirmed by medical record review when available,” the agency wrote.
“The analyses of all GBS cases based on claims data suggest an increased risk of GBS during the 42 days following vaccination, with an estimated 9 excess cases of GBS per million doses of Abrysvo, and an estimated 7 excess cases of GBS per million doses of Arexvy administered to individuals 65 years of age and older,” the FDA said.
For both vaccines, the risk of developing GBS is increased 42 days post-inoculation.
Although the FDA acknowledged a heightened risk for GBS, the agency noted that the “available evidence is insufficient to establish a causal relationship.”
American Faith reported that Moderna paused its mRNA RSV vaccine trial for children after five infants were hospitalized with severe respiratory complications. The decision followed similar safety concerns acknowledged by the FDA, which halted enrollment in related trials for children under two years old.
