FRIDAY, Oct. 22, 2021 (HealthDay News) -- The U.S. Centers for Disease Control and Prevention on Thursday gave its blessing to booster shots of the Moderna and Johnson & Johnson coronavirus vaccines for tens of millions of Americans.
The CDC approval mirrors the one granted by the U.S. Food and Drug Administration on Wednesday and follows its own endorsement last month of Pfizer booster shots. Now, many Americans will be able to get a booster shot as early as Friday, health officials said. Importantly, the CDC also endorsed the mixing and matching of vaccines, giving state and local health officials greater flexibility in getting booster shots to Americans who need them.
"The evidence shows that all three COVID-19 vaccines authorized in the United States are safe -- as demonstrated by the over 400 million vaccine doses already given. And, they are all highly effective in reducing the risk of severe disease, hospitalization and death, even in the midst of the widely circulating Delta variant," CDC Director Dr. Rochelle Walensky said in a statement released Thursday evening. Earlier in the day, the CDC's vaccine advisory panel endorsed both booster shots and mixing and matching vaccines.
The news will be particularly reassuring for the 15 million Americans who got the Johnson & Johnson vaccine, many of whom have been afraid that they are vulnerable to breakthrough infections because of that shot's lower level of protection.
"I agree that those who received a [Johnson & Johnson] vaccine should receive a second dose — I would prefer that those individuals get an mRNA vaccine [Pfizer of Moderna]" rather than a second Johnson & Johnson shot, said CDC vaccine advisory panel member Pablo J. Sanchez, a pediatrician at Ohio State University, the Washington Post reported.
"I think the opportunity for these [mix and match] boosts [is] priceless," said Helen Keipp Talbot, an infectious disease doctor at Vanderbilt University and CDC vaccine advisory panel member, the Post reported.
The CDC plans to release guidance early next week about who might benefit from choosing one booster over another, as its advisory panel requested. CDC advisers and agency officials are still working out whether to recommend that some people stick to their original vaccine if possible.
In its Wednesday approval, the FDA recommended that:
"Today, the currently available data suggest waning immunity in some populations of fully vaccinated people, and the availability of these authorized boosters is important for continued protection against COVID-19 disease," acting FDA Commissioner Dr. Janet Woodcock said during a Wednesday media briefing on the agency's booster approvals.
The guidelines for Moderna vaccine recipients eligible for a booster shot echo those set late last month for people who got the Pfizer vaccine.
One difference -- the Moderna booster will be a half-dose of the original vaccine, while the Pfizer booster is a full dose, the FDA said.
The agency also authorized "mix-and-match" booster doses after reviewing clinical trial data showing that an extra shot of any vaccine will provide added protection to anyone who's developed vaccine immunity, the FDA said.
"In many ways, as we move to deal with this as an infectious disease that we have to deal with, being able to interchange these vaccines is a good thing," Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, said during the Wednesday media briefing. "It's like what we do with flu vaccine. Most people don't know what brand flu vaccine they receive."
"If people have concerns, they should ask their providers and there might be reasons why an individual provider might decide to recommend a different booster based on side effects that were seen" during their initial series of shots, he added.
In the National Institutes of Health study on "mix-and-match" COVID-19 boosters, researchers looked at nine groups of roughly 50 people each. Each group received one of the three authorized vaccines, followed by a booster. In three groups, volunteers received the same vaccine for a boost. In the other six, they got a different vaccine.
The differences were startling: Those who got a J&J shot followed by a Moderna booster saw their antibody levels rise 76-fold within 15 days, while those who got a second dose of the J&J vaccine saw only a fourfold rise during the same period. A Pfizer booster shot raised antibody levels in Johnson & Johnson recipients 35-fold.
Nirav Shah, president of the Association of State and Territorial Health Officials, told the Post that the approval of the mix-and-match approach would make outreach efforts for boosters a simpler task.
The ability to mix and match boosters means that "when our teams are going into a community or a nursing facility to provide boosters, being able to carry one vaccine and give it to all who are eligible speeds up the process," Shah explained.
Meanwhile, regulators are seriously considering authorizing booster shots for people as young as 40, according to two officials familiar with the plans, the Post reported. That would not happen until the pediatric vaccine is authorized, said the officials, who spoke on the condition of anonymity.
About 105 million fully vaccinated people have received the two-shot Pfizer series, according to the CDC. About 70 million fully vaccinated people have received the Moderna shots. Only 15 million Americans were vaccinated with Johnson & Johnson shots, which arrived later and were delayed by an investigation of a rare adverse event, as well as a manufacturing problem. More than 11 million people have received a booster or an additional dose of a vaccine to date.
Visit the U.S. Food and Drug Administration for more on COVID vaccines.
SOURCE: U.S. Centers for Disease Control and Prevention, news release, Oct. 21, 2021; Oct. 20, 2021, media briefing with: Janet Woodcock, MD, acting commissioner, U.S. Food and Drug Administration, and Peter Marks, M.D., Ph.D., director, FDA's Center for Biologics Evaluation and Research; U.S. Food and Drug Administration, news release, Oct. 20, 2021; Washington Post