PHOTO
Image used for illustrative purpose. Six-year-old Diego Sanson receives an influenza vaccine injection at Massachusetts General Hospital in Boston, Massachusetts January 10, 2013.
GSK and Pfizer's respiratory syncytial virus (RSV) vaccines will carry warnings that they can increase the risk of developing a rare neurological disorder, the U.S. Food Drug Administration said on Tuesday.
The regulator conducted a postmarketing trial which suggested increased risk of Guillain-Barré syndrome (GBS) 42 days following vaccination.
However, the available evidence was insufficient to establish a causal relationship, the FDA said.
The risks flagged in the prescribing information of GSK's Arexvy and Pfizer's Abrysvo were not the regulator's strictest "boxed" warnings.
GBS is a rare disorder in which the body's immune system damages nerve cells, causing muscle weakness and sometimes paralysis. RSV, which typically causes cold-like symptoms, is a leading cause of pneumonia in toddlers and older adults.
In Arexvy's clinical trial, a participant had developed GBS after receiving the vaccine, while in Abrysvo's trial, one participant developed the disease and another got a variant of it.
Last year, advisers to the U.S. Centers for Disease Control and Prevention had postponed endorsing Arexvy's use in the 50-59 age group. They had also flagged the risk of GBS.
(Reporting by Puyaan Singh in Bengaluru; Editing by Devika Syamnath)