Millions of Americans According to the federal decision made on Thursday night and Friday, those whose immune system has been damaged by disease or medical treatment and who have been fully vaccinated with Pfizer or Moderna vaccine will be allowed to receive the third dose.
The decision of the Immunization Practice Advisory Committee, an external advisory group of the U.S. Food and Drug Administration and the U.S. Centers for Disease Control and Prevention, has allowed U.S. health policies to catch up with studies showing transplant recipients and cancer patients Not adequately protected Two injections-also suitable for patients who have already obtained unapproved doses on their own. In fact, it changed the authorized vaccine series for people with weakened immune systems from two doses to three doses, with the third dose being available 28 days or more after the second dose.
But this is not a comprehensive change. It only covers people with what the FDA and ACIP call “moderate to severe immune damage”. It only allows people 12 years and older to get the third shot because there is no authorization for the vaccine for teenagers or children. And it does not approve any additional injections for the immunocompromised population among the 12 million single-dose Johnson & Johnson vaccine recipients, because there is currently no data to predict their response.
Both the FDA and the committee are careful not to refer to the third dose as a “booster”, hoping to differentiate between improving the initial protection of people with weakened immune systems and restoring the immunity of other populations if the vaccine’s effectiveness against future variants diminishes. However, this move may still be controversial on a global scale. The World Health Organization has pleaded with rich countries to stop providing additional doses until poor countries can get more vaccines.
The decision to increase the dose for immunocompromised people has been around for some time. ACIP, a group of medical researchers and representatives of professional associations that help CDC Shaping vaccine policy, Checked the evidence of moving last month. CDC Director Rochelle Walensky said in a briefing by the White House Covid-19 Response Team on Thursday afternoon that he was about to arrive. “This action is to ensure that our most vulnerable people-they may need additional doses to enhance their biological response to the vaccine-are better protected from Covid-19,” she said.
U.S. Food and Drug Administration Changed its guidance Regarding the vaccine on Thursday night, the emergency use authorization of the Pfizer and Moderna formula was modified to include a three-dose series, and laid the foundation for the committee that has been scheduled to discuss it on Friday morning. The meeting ended with a unanimous vote for the third dose.
However, the immediate trigger for this change—and the surge in the highly contagious Delta variant that is sweeping the United States—is from Canada and France Published on Wednesday and Thursday New England Journal of Medicine (Although shared with federal agencies in advance). Both recorded low antibody levels in a small group of transplant recipients who received two vaccinations, but gained significant immune protection after the third vaccination.
“I really believe these results are certain; I think this is a slam dunk,” Atul Humar, a doctor and transplant director at the University of Toronto and senior author of the Canadian trial, said Thursday before the FDA and CDC took action. This study of 120 organ transplant patients showed that compared with participants who received placebo, recipients of the third dose not only improved antibodies, but also had higher T cell responses. “I think the results are convincing enough that this will lead to changes in regulatory guidelines and recommend a third dose for these patients,” he said.