Recently approved vaccines for respiratory syncytial virus (RSV) for older adults may be linked to a rare nervous system disorder that causes the body’s immune system to attack its own nerves.
In a Feb. 29 meeting of the Advisory Committee on Immunization Practices, health officials presented data that appears to show a slightly elevated rate of Guillain-Barré syndrome (GBS) among people who received RSV vaccines by Pfizer and GlaxoSmithKline (GSK).
A data mining alert on Jan. 19 for disproportional reporting was detected by the U.S. Food and Drug Administration (FDA) for Pfizer’s Abrysvo RSV vaccine and GBS but has not been reported to date for GSK’s RSV vaccine Arexvy, according to Dr. Tom Shimabukuro, deputy director of the CDC’s influenza division and former director of the CDC’s immunization safety office.
The FDA uses data mining to identify statistical associations between products and events in their respective safety databases. If there is disproportionate reporting of an event for a particular product, this could suggest a statistical association between the adverse event and the product.
According to data from the Vaccine Adverse Event Reporting System (VAERS) presented by Dr. Shimabukuro, data show 35 reports of GBS with 18 cases attributed to Pfizer’s vaccine, Abrysvo, 16 cases attributed to GSK’s Arexvy, and one case that was not reported under either brand name.
The CDC verified 23 cases of GBS reported to VAERS as of Feb. 16—all occurring within 22 days of RSV vaccination. Of the 23 cases, 15 were attributed to Pfizer’s vaccine and eight to GSK’s vaccine. Fourteen males experienced the condition compared with nine females. There was one death reported in a 70-year-old man who developed GBS after receiving Arexvy.
“Certainly 23 cases of GBS within 22 [days] of RSV vaccination is not a ‘small signal’ given the woeful underreporting in VAERS,” Brian Hooker, chief scientific officer at Children’s Health Defense, who holds a doctorate in biochemical engineering, told The Epoch Times in an email.
“What is always missing with VAERS is a good denominator. Given that these vaccines have been distributed for less than a year (since May 31, 2023), I would expect the uptake to still be fairly low,” he added.
According to the Department of Health and Human Services (HHS), underreporting is one of the main limitations of a passive surveillance system like VAERS. “The term, underreporting refers to the fact that VAERS receives reports for only a small fraction of actual adverse events,” HHS states on its website. A November 2020 article published in Vaccine showed sensitivity for capturing GBS after three different vaccines ranged from 12 to 64 percent, suggesting more cases of GBS are occurring than are being captured.
Vaccine Safety Database Suggests ‘Potential’ for Increased Rate of GBS
The CDC’s Vaccine Safety Datalink (VSD) suggests the “potential for an increased rate of GBS” following vaccination with GSK’s Arexvy RSV vaccine, but the agency said additional analyses are needed. There were insufficient doses of Pfizer’s Abrysvo used in the VSD to determine the risk of GBS following vaccination.
It is estimated that 10 people will experience GBS for every 1 million doses of Arexvy administered, compared with 25 cases of Abrysvo, the CDC’s vaccine advisors said during the meeting.
Due to the small number of GBS cases and the size of the prelicensure studies, Dr. Shimabukuro said it’s not known at this time whether the reported GBS cases or other neuroinflammatory events are random chance or whether RSV vaccination might increase the risk of these events. However, GBS is already included as an adverse event on both companies’ vaccine labels.
In prelicensure studies of Prizer’s RSV vaccine in adults 60 and older, two reported cases of GBS among 20,255 vaccine recipients were observed within 42 days of vaccination compared with one case during GSK’s study of 18,304 vaccine recipients.
“We’re still in the early uptake phase of these new RSV vaccines,” Dr. Shimabukuro told STAT in an interview after the meeting. “Some of these data and findings are based on small numbers of cases and relatively small numbers of doses administered,” he added. Due to “uncertainties and limitations” of early data, Dr. Shimabukuro said the agency can’t establish whether there’s an increased risk for GBS in individuals 60 and older following RSV vaccination, but better risk estimates would be forthcoming in the future.
During the meeting, Pfizer vice president Reema Mehta said the company believes its vaccine is safe but is committed to continuous monitoring and evaluation of Abrysvo’s safety to assess the possibility of vaccine-related GBS.
In an email to STAT, a spokesperson for GSK said the CDC analysis did not indicate an elevated rate of GBS among people who had received their company’s RSV vaccine, but it is designing a study to evaluate the risk of GBS after vaccination with Arexvy.
Mr. Hooker said what’s more shocking to him is the 34 deaths reported from RSV vaccine in a short period of time. The deaths were included in Dr. Shimabukuro’s presentation during the ACIP meeting.
“The swine flu vaccine was taken off of the market for fewer deaths,” Mr. Hooker told The Epoch Times. “It seems that with the advent of the horrific result of the COVID-19 vaccine, the bar has been severely lowered in terms of overall safety.”
The CDC said during the meeting that its risk-benefit analysis continues to support the use of both RSV vaccines in people over 60 due to the burden of RSV in that population.
GBS Reported After Other Vaccines
The FDA, in May 2023, licensed Pfizer and GSK’s RSV vaccines for adults 60 and older. The CDC signed off on a recommendation made by its advisory panel shortly thereafter recommending the vaccine for people 60 and older only if a healthcare provider thinks vaccination would be beneficial versus making it an annual vaccine. Some vaccine advisors proposed making a universal recommendation for RSV and requested more data at the upcoming meeting scheduled in June.
According to the CDC, RSV is a common respiratory virus that usually causes mild, cold-like symptoms. Although most people recover in a week or two, it can be serious and is more commonly diagnosed in infants.
GBS is a rare neurological disorder that occurs when a person’s immune system attacks the peripheral nervous system—a network of nerves that carry signals from the brain and spinal cord to other areas of the body. The condition begins suddenly with weakness and tingling in the hands and feet and eventually spreads throughout the body, resulting in paralysis that can leave a person unable to breathe independently.
Although most people recover from GBS, some cases are severe and can be fatal. Recovery can take several years, and it may take six months or longer after symptoms start for an individual with GBS to walk again.
Miller Fisher syndrome (MFS) and Bickerstaff brainstem encephalitis (BBE) are two variants of GBS. MFS is a nerve disease that usually involves the lower cranial and facial nerves, and BBE involves altered consciousness, problems with muscle coordination, and impaired eye movements.
Other vaccines have also been linked to GBS, including COVID-19, recombinant zoster, and influenza vaccines. CDC studies based on data from the VSD and VAERS found an increased risk of GBS among adults 18 and older following COVID-19 vaccination with the Johnson & Johnson (J&J) shot manufactured by Janssen. The FDA, in July 2021, announced revisions to the product fact sheets for J&J to include a warning related to the increased risk of GBS observed following vaccination.
Although the agency said it has not observed a similar signal with mRNA vaccines by Pfizer and Moderna, cases of GBS and its variants have been reported following vaccination with both vaccines to VAERS and by the scientific community.
