Blood sample for respiratory syncytial virus (RSV) test.
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On Tuesday, independent advisers to the Food and Drug Administration really useful the world’s first RSV vaccine, an injection of Pfizer for adults aged 60 and over, despite safety concerns after two study participants developed a rare neurological disorder.
Most members of the FDA committee supported the vaccine, but struggled with separate voices over whether the safety and efficacy data were sufficient to support the agency’s approval. The FDA is predicted to make a call in May.
There may be currently no vaccine to guard the elderly against respiratory syncytial virus, which kills hundreds of seniors every year. Pfizer’s injection could develop into the first to receive FDA approval.
In the first vote on Tuesday, seven members of the FDA committee said the safety data were appropriate for approval, while 4 said it was not, and one member abstained.
The vote followed concerns from the FDA and advisory committee members about two cases of Guillain-Barre syndrome in roughly 20,000 vaccinated people. Guillain-Barre is a rare neurological disorder through which the body’s immune system mistakenly attacks the nerves.
Symptoms can range from transient weakness to paralysis. Most patients, even those with severe cases, recuperate.
On the second vote, seven committee members said the vaccine efficacy data were adequate, while 4 said they didn’t, and one member abstained.
In keeping with a Pfizer review of the data, the injection provided about 86% protection against lower respiratory disease with three or more symptoms and 66.7% protection against the same disease with two or more symptoms. Symptoms included wheezing, shortness of breath, rapid and shallow respiratory, and mucus production.
In keeping with the Centers for Disease Control Prevention, in adults aged 65 and older, RSV causes 6,000 to 10,000 deaths and 60,000 to 160,000 hospitalizations annually. The danger of hospitalization increases with age, with adults aged 70 and over being more in danger.
Amongst adults of all ages hospitalized for RSV, 19% require intensive care and 4% die, in keeping with CDC data for three seasons. Mortality is highest amongst seniors.
Pfizer’s vaccine comprises each RSV strains that flow into at the same time in fall and winter. The injection is given as a single dose of 120 micrograms.
Guillain-Barre affairs
The FDA believes the two cases of Guillain-Barre during the trial were likely linked to the vaccine, said Dr. Nadine Peart Akindele, an agency representative. The FDA asked Pfizer to develop a security study to watch Guillain-Barre’s risks after approval, which the company agreed to do.
A 66-year-old man in the US developed Guillain-Barre, and a girl of the same age in Japan was diagnosed with Miller Fisher syndrome, a variant of Guillain-Barre. Symptoms developed seven and eight days after vaccination, respectively. In keeping with the FDA, the woman has since recovered and the man’s symptoms have improved since the last update.
Nonetheless, Alejandra Gurtman, Pfizer’s chief executive, maintained that the company had not identified any safety concerns during the trial and that the vaccine was well tolerated.
Gurtman pointed to other potential causes of the Guillain-Barre cases, noting that the man suffered a heart attack and the woman had an upper respiratory infection. But Dr. Marie Griffin, a member of the FDA’s advisory committee, said the cases raise serious safety concerns.
“I feel one case is a red flag. The 2 cases are very concerning, and it worries me that Pfizer doesn’t consider there are any safety concerns,” said Griffin, a professor of health policy at Vanderbilt University Medical Center.
The FDA says safety monitoring is critical
Dr. Hana El Sahly, who chairs the FDA’s advisory committee, also said the Guillain-Barre cases raise serious safety concerns. El Sahly said the prevalence of the disease is around 1 in 100,000 amongst people aged 60 and over, but in the study the rate looks more like 1 in 9,000.
“In order that’s vital if we take it at this level,” El Sahly said, while noting that there is critical uncertainty about the true rate of disease amongst people receiving vaccines. “Nevertheless, it is critical by way of prevalence,” she said.
Dr. David Kaslow, a senior official in the FDA’s vaccines division, said safety monitoring can be “critical” if Pfizer’s RSV vaccine is approved.
The FDA is currently reviewing Pfizer’s proposal to analyze the risk of Guillain-Barre syndrome amongst Medicare beneficiaries. The FDA has the right to require such a post-approval study if deemed needed.
Dr. Jay Portnoy, a member of the FDA committee, said he concluded that the safety data is suitable because Guillain-Barre syndrome is rare, and the study’s opposed events occurred at about the same rate amongst individuals who received the vaccine. and people who didn’t receive it. .
Adam Berger, an official at the National Institutes of Health, said he was concerned about the Guillain-Barre cases, but said a bigger research population was needed to find out if there was an actual link to the injection. He said a post-approval study planned by the FDA and Pfizer could help answer that query.
“I felt like I could vote yes at this point, with a powerful bias towards the actual requirements of this postmarketing surveillance study,” said Berger, who can be a member of the FDA committee.
Incomplete efficacy data
In keeping with the FDA, at Tuesday’s meeting there was not enough data to guage the effectiveness of Pfizer’s vaccine against severe illness requiring hospitalization, oxygen support or a mechanical ventilator. There was also no data available on how long protection against the vaccine would last, in keeping with the agency.
In keeping with the FDA, Pfizer also had no data on the effectiveness of the vaccine for elderly individuals with weak immune systems or those sick.
Griffin, a physician at the Vanderbilt University Medical Center, said she was concerned that the vaccine was tested in a comparatively healthy population where hospitalizations were low, and that there have been no data on nursing home residents and people in frail health .
Akindele, an FDA official, said real-life evidence after the vaccine was introduced could answer the query of what protection it offers to those in frail health. She said the data would then be used to find out if the FDA needed to make any changes to how the injection was used.
Pfizer conducts clinical trials over two seasons of RSV involving greater than 34,000 people. Available efficacy and safety data are from the first season.
When asked what would have happened if season two’s data hadn’t been as strong after approval, Akindele said the FDA would re-evaluate the shot and meet with the committee again to find out how one can proceed.
Pfizer estimates that if 50% of individuals aged 60 and older receive the vaccine, the vaccine could prevent greater than 5,000 deaths, 68,000 hospitalizations, 51,000 emergency department visits and greater than 422,000 outpatient visits.