• Posted March 2, 2023

FDA Panel Backs Second RSV Vaccine for Older Americans

Following hours of discussion over safety concerns, a U.S. Food and Drug Administration advisory panel on Wednesday recommended approval of a second RSV vaccine, this one made by GlaxoSmithKline, for use in Americans ages 60 and older.

The panel's recommendation was based largely on the results of a trial that tested the GlaxoSmithKline vaccine in the same age group. Those findings, published recently in the New England Journal of Medicine, showed that the shot lowered the risk of symptomatic illness by 83% and of severe illness by 94% in people ages 60 and up.

In a two-part vote, the panel voted 10 to 2 in favor of the vaccine's safety and unanimously on the shot's effectiveness, the New York Times reported.

Meanwhile, the same panel on Tuesday recommended the approval of an RSV vaccine known as RENOIR from Pfizer Inc.

On both days, panel members debated the benefits of the vaccines for patients who overwhelmingly avoided hospitalization against rare reports of autoimmune conditions like Guillain-Barré syndrome that emerged shortly after the shots were administered.

In addition, two people who were given the GSK vaccine developed acute disseminated encephalomyelitis, a neurological disorder with symptoms that include weakness and loss of vision. One person died. The company and the FDA consider the cases "possibly related"to the vaccine, noting that both patients also received a flu vaccine at the same time as the RSV shot, the Times reported.

Watching the safety of both vaccines after they are approved will be critical, Dr. Henry Bernstein, from the Zucker School of Medicine at Hofstra University in New York, told the Times.

"I don't know that there's a rush to get this to market if we're going to take two steps forward, and three steps back as far as public health and optimizing vaccination rates,"Bernstein noted.

Both Pfizer and GSK have said they would conduct continuing safety monitoring of the vaccines if they were approved by the FDA, which typically follows the advice of its advisory panels. The U.S. Centers for Disease Control and Prevention would also need to recommend the shots before they could become available to Americans.

Still, the FDA advisors were divided in their recommendation on the Pfizer vaccine in particular. The panel voted 7-4, with one abstention, to recommend approval of the vaccine based on its effectiveness, NBC News reported. FDA advisors were also split, 7-4 with one abstention, on the safety for the Pfizer vaccine.

The vaccine's potential association with a rare neurological disorder known as Guillain-Barré syndrome (GBS) was a concern for those who voted against approval because of safety.

"It was a 1 in 9,000 risk of GBS, which is concerning,"said committee chair Dr. Hana El Sahly, who voted against the shot based on its safety profile but in favor of the shot based on its efficacy.

Common side effects of both the Pfizer and the GSK vaccines were injection site and muscle pain and fatigue. Pfizer participants reported headaches, while the GSK participants reported more frequent side effects, according to NBC News.

Pfizer has reported that its vaccine would reduce risk from RSV by as much as 86%.

These may not be the only RSV vaccines to come, as 11 are being studied in U.S. trials now, according to data from nonprofit global health organization PATH, NBC News reported. Those include vaccines from Moderna and Bavarian Nordic.

Pfizer has also tested its RSV vaccine in pregnant women. An FDA decision on that is expected in August. That vaccine reduced the risk of severe illness in infants by 82% through the first 90 days of life, NBC News reported.

A monoclonal antibody injection designed for babies is also under FDA review. That shot is from Sanofi and AstraZeneca and has already been approved in Europe, NBC News reported.

Although RSV infection is mild for for many people, the disease can be very serious for infants and older adults. It kills up to 10,000 adults ages 65 or older each year, according to the CDC. Meanwhile, about 300 U.S. children under the age of 5 also die from RSV each year.

More information

The U.S. Centers for Disease Control and Prevention has more on RSV.

SOURCE: NBC News