The U.S. is expected to soon authorize two COVID-19 booster shots for people with compromised immune systems in a move that underscores the risk that the virus still poses to some vaccinated Americans.
The Food and Drug Administration “is working with Pfizer and Moderna to allow boosters for these vulnerable people,” Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention, said Thursday during a White House briefing. “An additional dose could help increase protection for these individuals, which is especially important as the delta variant spreads.”
She added that the FDA’s announcement is expected to be made in advance of the CDC advisory committee’s meeting, which is scheduled Friday. The committee is expected to decide whether the CDC should recommend an extra shot for people who are immunocompromised.
This will be the first regulatory authorization in the U.S. for any kind of COVID-19 booster shot. Other countries, including Israel, France, and Germany, have said they will allow some members of their populations to get an extra shot.
It will also come at a time when there is growing awareness of breakthrough infections among Americans who have been vaccinated amid a surge of daily cases that is on par with early February’s numbers.
Physicians say the most serious of these breakthrough cases are occurring in the immunocompromised, including organ-transplant patients, people undergoing chemotherapy, Americans taking chronic medications that can suppress their immune systems, and the elderly.
The FDA authorization, however, isn’t expected to include the elderly.
“We do not believe that others—elderly or non-elderly who are not immunocompromised—need a vaccine right at this moment, but this is a dynamic process and the data will be evaluated,” Dr. Anthony Fauci, chief medical adviser to President Joe Biden, told reporters on Thursday.
This is a sharp turn in thinking from a month ago, when the CDC and the FDA put out a joint statement on July 8 that said fully vaccinated people do not need an extra dose.
The FDA didn’t confirm that it is planning to update the emergency-use authorizations for Pfizer Inc.
and Moderna Inc.’s
COVID-19 vaccines to include booster shots, as reported by multiple media outlets. (Both vaccines are mRNA shots that had similar efficacy rates in clinical rates.)
However, the regulator told MarketWatch that “the agency, along with the CDC, is evaluating potential options on this issue, and will share information in the near future.”
Breakthrough infections are still considered rare among the more than 167 million Americans who have been fully vaccinated. However, there is anecdotal evidence and some research demonstrating that a small but increasing number of individuals who are fully immunized are getting sick or testing positive for the virus. Most are reporting mild and moderate infections.
Nearly all of the hospitalizations and deaths occurring right now are in people who are unvaccinated; a July 30 analysis conducted by the Kaiser Family Foundation of somewhat limited data provided by 16 states found that breakthrough hospitalizations made up 5% or less of hospitalizations and 3% or less of deaths.
The U.S. isn’t broadly tracking the number of breakthrough infections that are occurring, and it’s understood that vaccine-induced immunity can wane in some people, in part because the vaccines we have may be less protective against the more contagious delta variant.
Fauci noted during the briefing that boosters will be necessary for the general public at some point. “Sooner or later you will need a booster for durability of protection,” he said.
It’s a much more worrisome scenario for people who are immunocompromised.
Immunocompromised people likely make up between 3% to 4% of the U.S. population, according to George Yancopoulos, president of Regeneron Pharmaceuticals Inc. REGN, in remarks last week about the company’s monoclonal antibody treatment.
He also said that about half of these individuals do not mount an immune response after sometimes “three attempts with the vaccine,” according to a FactSet transcript of the investor call.
Some early research, however, has indicated that an extra dose can boost the immune response in these patients. A third dose of the BioNTech BNTX and Pfizer vaccine in solid organ transplant patients “significantly improved the immunogenicity of the vaccine, with no cases of COVID-19 reported,” a group of physicians in France wrote in the New England Journal of Medicine on Thursday.
“A lot of the immunocompromised patients we’ve had who’ve come in have indeed been organ transplant patients who’ve taken every precaution they could,” said Dr. Nida Qadir, associate director of the medical ICU at the Ronald Reagan UCLA Medical Center in Los Angeles. “They got vaccinated when they could. And so they often are surprised and also really frustrated because they felt like they did their part and, unfortunately, got sick in spite of that.”