A panel of independent vaccine experts from the U.S. Food and Drug Administration met on Thursday to discuss the future of COVID-19 shots. The FDA has released a document revealing that the agency is sticking to the idea that the COVID vaccine fits into the mold of the annual flu shot. winter waves.
However, outside experts, including some on the FDA’s advisory committee, believe that the uncertain seasonality of COVID-19 so far has made tracking fast-moving variants (and possibly subspecies) futility. to question almost every aspect of that plan. ). Some even question whether young and healthy people need to be boosted so often when current vaccines offer protection against severe disease but only short-term protection against infection. doing.
One of the most outspoken members of the FDA panel, Paul Offitt, a pediatrician and infectious disease expert at Children’s Hospital of Philadelphia, wrote a commentary article in the New England Journal of Medicine earlier this month titled: wrote and openly attacked the bivalent booster. Vaccines — Cautionary Note. (Last year, the FDA’s advisory panel voted him 19 to 2 in favor of the bivalent booster, with Offit having one of two votes against.)
Still, despite the troubled backdrop to yesterday’s meeting, the sparks of disagreement were extinguished in a calm discussion.The nine-hour meeting culminated in a unanimous vote by the committee. reached and advocated “harmonizing” future prescribing of COVID-19 vaccines, with primary series and booster matching prescribing. For example, the first-line vaccine now targets both the original strain of SARS-CoV-2, which originated from Wuhan, China, and the Omicron subvariant BA.4/5, his updated bivalent Match boosters.
Rationalization
The FDA appears to have softened its position on a topic of questions and discussion focused on “harmonization” and simplification of COVID vaccines. ‘, and then proceeded to the more dangerous but mild topic of discussion of considering ‘regular updates to the COVID-19 vaccine composition’.
Overall, committee members favored rationalizing vaccines where possible. The primary series of shots may be matched with booster doses, reducing the regimen to 1 dose for adults and 2 doses for children and high-risk adults.
Archana Chatterjee, dean of the Chicago Medical School and member of the voting committee, said: I said at the end of yesterday’s meeting. “I agree with other colleagues that there is definitely a need for these vaccines and that we need to do our best to weaponize them. , should be used….This is a step…in the right direction to get us there.”
But the bigger steps for future vaccines — deciding which formulation to use next, who will get them and when, remained an elephant-sized question in the conference room. Even during the
Prior to the committee’s vote and discussion, advisors listened to a series of presentations from vaccine manufacturers, the FDA, and the Centers for Disease Control and Prevention. All of these provided an update on the status of COVID-19 and the performance of vaccines to date. .
data dive
Offitt et al. criticized the bivalent booster as not superior to previous boosters, but argued that the data presented at the conference did not. A comparison shows the benefits of people boosted with bivalent boosters. Data presented during the conference show superiority to the original vaccine in terms of protection against symptomatic infections, emergency department or emergency care visits, and hospitalization.
For example, in a CDC study released Wednesday, researchers found the relative efficacy of a bivalent booster against symptomatic infections by BA.5-related omicron substrains (including BQ.1 and BQ.1.1). are between the ages of 18 and 49. In other words, people in this age group were 52% more protective against infection with BA.5-related strains than those who received the first booster. The relative efficacy was 43% and 37% in those 65 years and older.
For the more recent XBB/XBB.1.5-related omicron variants, the relative efficacy against infection was 49% in people aged 18-49, 40% in people aged 50-64, and 65 and older. was 43%.
A number of serological studies have also been conducted to examine how the antibody response of the bivalent booster compares with that from the original booster against the full range of currently circulating omicron subspecies. Results have been mixed and, in some cases, different intervals between vaccinations, different numbers of people involved, and different types of assays used, making comparisons difficult. and against the recently prevalent Omicron subvariant, suggesting that it provides a superior neutralizing antibody response than the original vaccine.
“The important thing is that the results are all heading in the same direction,” Jerry Weir, director of the FDA’s Office of Viral Products, said at a meeting Thursday. Studies, similar to those by manufacturers, show improved variant-specific neutralization after administration of a bivalent BA.4/5 vaccine compared to a monovalent vaccine..Uniform.”
For example, one of the latest studies, published Wednesday in the New England Journal of Medicine, found that bivalent boosts reduced neutralizing antibody levels against XBB.1 compared to people boosted with the first booster. found to lead to an approximately three-fold increase in The increases were similar (3.6-fold and 2.7-fold) between previously uninfected and previously infected persons with SARS-CoV-2, respectively.
Despite criticism by Offit et al. before the meeting, panel members appeared satisfied with the bivalent data and accepted the FDA’s optimistic retrospective.
Board member David Kim, an infectious disease expert at the Department of Health and Human Services, said: “We are absolutely convinced that a bivalent vaccine would be beneficial both as a primary vaccine and as a booster.
