top of page
  • Extremely American

Pfizer’s RSV Vaccine Linked to Guillain-Barré Syndrome, Disreputable Drugmaker claims It’s ‘Safe'

Pfizer’s RSV Vaccine for Older Adults Linked to Guillain-Barré Syndrome, But Drugmaker Says It’s ‘Safe’

People who receive Pfizer’s respiratory syncytial virus vaccine should be monitored for Guillain-Barré syndrome, according to the authors of a Pfizer-funded study published this week in the New England Journal of Medicine.

April 10, 2023: People who receive Pfizer’s respiratory syncytial virus (RSV) vaccine should be monitored for Guillain-Barré syndrome, according to the authors of a Pfizer-funded study published this week in the New England Journal of Medicine (NEJM).

The paper — one of several published Wednesday reporting interim analyses for Pfizer’s phase 3 clinical trials for the RSV vaccine — concluded the vaccine was effective in preventing RSV in adults age 60 and over “without evident safety concerns.”

But that same article also flagged Guillain-Barré syndrome as a safety concern moving forward with the vaccine.

“If RSVpreF vaccine [Pfizer’s RSV vaccine] is approved and recommended, these adverse events warrant close monitoring in future studies and with real-world data and post-marketing surveillance,” the authors of the NEJM study said.

The U.S. Food and Drug Administration (FDA) is expected to approve Pfizer’s RSV vaccine for older adults in May.

Safe and effective?

Guillain-Barré syndrome is a rare disorder in which the body’s immune system attacks its own nerves. Symptoms can range from brief weakness to paralysis.

The FDA asked Pfizer to include the condition as an “important potential risk” of the vaccine and to develop a safety study to monitor for potential cases if the shot is approved, CNBC reported.

When the FDA vaccine advisory panel met in February to review Pfizer’s data pre-publication, there was substantial disagreement about the data on safety and effectiveness, although the majority of the committee voted to recommend the vaccine for approval.

Four of 12 committee members voted that the safety data was not adequate for approval — and one abstained — because of their concerns with the Guillain-Barré cases.

Four committee members also voted the evidence of vaccine effectiveness was not adequate for approval, while seven said it was and one member abstained.

In the NEJM study, one person developed Guillain-Barré syndrome and another developed Miller Fisher syndrome, a subset of Guillain-Barré. The symptoms appeared six and seven days post-vaccination, respectively.

The person with Miller Fisher syndrome recovered. The person diagnosed with Guillain-Barré continues to suffer from loss of motor function.

CNBC reported:

“In the New England Journal of Medicine article, the scientists said the two cases occurred in patients who were in an age group that has an increased risk of developing Guillain-Barré. Potential factors other than the vaccine also could have caused the individuals to develop the syndrome, they added.
“But the FDA said the agency views the Guillain-Barré cases as possibly related to the vaccine because the patients developed the syndrome shortly after receiving the shot, according to briefing documents published in February.
“Pfizer concluded that the cases were unrelated, and the clinical trial’s data monitoring committee did not identify any safety concerns with the vaccine.”

Dr. Hana El Sahly, the FDA committee chair and professor of molecular virology and microbiology and infectious diseases at the Baylor College of Medicine, said Guillain-Barré has an incidence of about 1 in 100,000 among people ages 60 and older. But in the vaccine trial, the rate was closer to 1 in 9,000, which is significantly higher.

“It’s significant in terms of incidence,” she said. The FDA advisors told Pfizer that safety monitoring for Guillain-Barré after FDA approval “would be crucial,” CNBC reported.

There is currently no vaccine approved to prevent RSV, a lower respiratory disease that is one of the most common causes of childhood cold-like illness and was first discovered in humans in 1956.

The illness is mild for most people.

In children under age 5, RSV causes 58,000 to 80,000 hospitalizations per year and 100 to 300 deaths.

In adults ages 65 and older, RSV causes 6,000 to 10,000 deaths and 60,000 to 160,000 hospitalizations per year, according to the Centers for Disease Control and Prevention.

Research shows the virus originated in monkeys housed in a Maryland facility where they were used to conduct polio vaccine research.

Brian Hooker, Ph.D., P.E., chief scientific officer for Children’s Health Defense (CHD), told The Defender:

“I find it ironic that Pfizer is creating a vaccine for RSV, an illness that was created due to the development of the polio vaccine. It seems like vaccine manufacturers are paid to prevent diseases that they already created.
“The incidence of Guillain-Barré is very troubling and although many patients recover, there is nerve damage associated with it leading to permanent weakness, numbness and fatigue.”

The NEJM study reported that the vaccine was 86% effective at preventing lower respiratory tract illness with three or more symptoms, and 66% effective at preventing the illness with two or more symptoms, among adults over age 60.

The study determined there were not enough cases of severe RSV-associated lower respiratory tract illness — meaning cases needing hospitalization or ventilation or extra oxygen — to determine whether the vaccine was effective for those cases, CNN reported.

RSV vaccines for pregnant women failed to meet major goal in trials

Pfizer is also seeking FDA approval for its vaccine to protect infants from RSV by vaccinating pregnant mothers.

However, in the interim data on clinical trials, also published Wednesday in the NEJM, the vaccine failed to meet one of its two main goals.

Last year, Pfizer reported that its vaccine was highly effective at protecting newborns from RSV. The drugmaker also sought rapid FDA approval for the vaccine for pregnant mothers.

The FDA is expected to decide by August.

According to the study published Wednesday, the vaccine was 82% effective in preventing severe lower respiratory tract illness — such as very low oxygen levels or need for ventilator support — in infants in the first 90 days of life, but that dropped to 69% efficacy up to 180 days after a baby is born.

But the vaccine failed to meet its second big goal: reducing non-severe RSV-associated lower respiratory illness in infants.

The study enrolled 7,128 women — half received the RSV vaccine and half received the placebo.

Severe illness occurred within three months in six infants whose mothers received the vaccine, compared with 33 infants from the placebo group who contracted serious RSV infections.

The company evaluated 3,570 infants as part of the study, Reuters reported.

Big Pharma’s race for the RSV vaccine

The RSV virus causes annual outbreaks of respiratory illnesses in all age groups, typically during the fall, winter and spring in most regions of the U.S. It has existed for decades and doesn’t usually spark alarm.

But RSV made headlines last fall as part of a “tripledemic” — COVID-19, flu and RSV — scare, just as these new RSV products were preparing to come on the market.

Robert F. Kennedy, Jr., CHD chairman-on-leave, said at the time, “fear sells,” tweeting:

As The Defender reported, pharmaceutical companies have been working on the development of a vaccine for RSV since the 1960s — at times with deadly outcomes.

After a disastrous attempt at producing a vaccine, where 80% of vaccinated children were hospitalized, RSV vaccine development was put on hold.

Over the last several years, “lured by the prospect of a large untapped global RSV vaccine market,” four manufacturers set their sights on RSV vaccine development for infants, pregnant women and the elderly.

Initially, Johnson & Johnson and Bavarian Nordic also were developing RSV vaccines, but the former dropped out of the race last month and Bavarian Nordic’s clinical trials are in progress.

That leaves Pfizer and GlaxoSmithKline (GSK), who have been in a tight race to be the first Big Pharma player to tap into the RSV vaccine market, which is estimated to be over $5 billion and could exceed $10 billion by 2030, Reuters reported last month.

Both companies have RSV vaccines under regulatory review with the FDA.

The FDA advisory committee voted unanimously in favor of GSK’s vaccine’s effectiveness in preventing lower respiratory tract disease caused by RSV in adults aged 60 and above, and voted 10 to 2 for its safety last month, based on interim data presented last October, Reuters reported.


bottom of page